Stuttering Energy Transitions: Germany – Consumers

The German Renewable Energy Act (German: Erneuerbare-Energien-Gesetz, EEG) was designed to encourage cost reductions based on improved energy efficiency from economies of scale over time. The Act came into force in the year 2000 and was the initial spark behind a tremendous boost of renewable energies in Germany.

The three main principles of the EEG are:

a) Investment protection through guaranteed feed-in tariffs and connection requirement: Originally, every kilowatt-hour generated from renewable energy facilities received a fixed feed-in tariff. The system has recently been modified to now also include a market premium system. Network operators are required to preferentially feed-in this electricity into the grid over electricity from conventional sources (nuclear power, coal and gas). Renewable energy plant operators in principle receive a 20-year, technology-specific, guaranteed payment for their electricity generation. Small and medium enterprises have been given new access to the electricity market, along with private land owners. The Federal Ministry for Environment, Nature Conservation and Nuclear Safety argued that anyone producing renewable energy could sell his ‘product’ for a 20-year fixed price.

b) No charge to Germany’s public purse: The promotion of renewable electricity continues to be necessary up until now. The EEG rates of remuneration show what electricity from wind, hydro, solar, bio- and geothermal energy actually cost. Compared to fossil fuels, there are lower or no external costs, such as damage to the environment, the climate or human health. The remuneration rates have until recently been considered not to be subsidies as such, since they are not paid for by taxes and are paid for by every consumer as an EEG surcharge (EEG-Umlage) that is included in the electricity bill. The polluter pays principle a.k.a “whoever consumes more, pays more” is in effect passed on to consumers. In 2013, the total EEG surcharge amounted to EUR 20.4 billion. In 2014, the EEG surcharge was set at 6.24 ct/kWh. Certain reductions of the EEG surcharge apply for energiy intensive industries (so-called special equalisation scheme).

c) Innovation by decreasing feed-in-tariffs: Feed-in tariffs in Germany decrease in regular intervals to exert cost pressure on energy generators and technology manufacturers. The decrease (called “degression”) applies to new plants. Thus, it is hoped, technologies are becoming more efficient and less costly.

The prices of electricity over this time period behaved as the figure below shows:

German Electricity Costs

Figure 1 – electricity prices in Germany since the EEG was introduced. The green line above is the price of electricity on the German electricity exchange. The red line is the average price of electricity for households. The other lines are for commercial clients and special customers (notably, their prices have also risen).

The price of electricity in Germany was high relative to other countries, as can be seen in Figure 3.

Average Price of Electricity Cost by Country

Figure 3 – The relative price of German electricity in 2011



As I mentioned in last week’s blog, more than 60% of the Germans were happy with the new energy policy. This, of course, leaves plenty of unhappy people. Any transition of this magnitude produces many winners and losers. They, in turn, keep the conversation going and serve as an excellent example for other countries, who can take notice, learn and adapt – thus pushing forward the global energy transition that will mitigate destructive changes in the physical environment.

Of the many aspects mentioned above, the feed-in tariff is key. Since its inception, some important changes have taken place, including:

  1.  Purchase prices were based on generation cost. This led to different prices for wind power, solar power, biomass/biogas and geothermal and for projects of different sizes.

  2. Purchase guarantees were extended to 20 years.

  3. Utilities were allowed to participate.

  4. Rates were designed to decline annually based on expected cost reductions, known as “tariff degression”.

Since it was the most successful, the German policy (amended in 2004 and 2008) often was the benchmark against which other feed-in tariff policies were considered.

Other countries followed the German approach. Long-term contracts are typically offered in a non-discriminatory manner to all renewable energy producers. Because purchase prices are based on costs, efficiently operated projects yield a reasonable rate of return.

This principle was stated as:

‘The compensation rates…have been determined by means of scientific studies, subject to the proviso that the rates identified should make it possible for an installation – when managed efficiently – to be operated cost-effectively, based on the use of state-of-the-art technology and depending on the renewable energy sources naturally available in a given geographical environment.’

—2000 RES Act

Feed-in tariff policies typically target a 5–10% return.

Feed-in tariffs (REFIT) supported growth in solar power in Spain, Germany and wind power in Denmark.

The success of photovoltaics in Germany resulted in an electricity price drop of up to 40% during peak output times, with savings between €520 million and 840 million for consumers. Savings for consumers have meant conversely reductions in the profit margin of big electric power companies, who reacted by lobbying the German government, which reduced subsidies in 2012. Energy utilities lobbied for the abolition, or against the introduction, of feed-in tariffs in other parts of the world, including Australia and California. Increase in the solar energy share in Germany also had the effect of closing gas- and coal-fired generation plants.

Some of the important losers over the years were the German utilities. An article by Leon Mangasarian and Stefan Nicola from Bloomberg that was published in Renewable Energy World summarized some of the important issues that they were facing. I am including few paragraphs below:

BERLIN — Germany’s biggest utilities face dwindling market shares as the shift to renewable energy spurs regional power generation and storage technology, a senior member of Chancellor Angela Merkel’s party said.

Electricity companies are ‘fighting something of their last stand,’ Christine Lieberknecht, the Christian Democratic Union premier of Thuringia state, said in an interview. ‘In a few years, nobody will even talk about it anymore because the technology for decentralization of power production and energy self-determination will make such strides.’

That vista suggests a deepening crisis for EON SE and RWE AG, Germany’s biggest utilities, whose profits are slumping as Merkel pushes plans to close all 17 German nuclear reactors by 2022 in response to the Fukushima meltdown in Japan in 2011. Both companies produce mostly conventional energy.

Germany’s energy landscape is shifting as renewable sources grab revenue while consumers and companies criticize rising power costs that are three times higher than in the U.S., in part due to taxes and subsidies to promote renewable energy. Merkel plans to more than triple Germany’s renewable share to 80 percent by 2050 from about a quarter now.

Essen-based RWE generated 6.4 percent of its power from alternative energy sources last year, compared with almost double that at Dusseldorf-based EON, Germany’s biggest utility by market capitalization.

As mentioned earlier, the feed-in tariff is destroying the business model of the electric utilities and serves also as a vehicle to subsidize the alternative energy producers. This will be further explored in the next blog, where I will shift to the producers.

In my last blog, I ended with a look at one at of the most fascinating recent developments of the German adaptations to these change – the splitting of the largest utility, E.ON into two companies. One of these will continue to be focused on fossil fuels while the other one will completely shift to the new alternative energies and integrating consumer demands with energy supply. This will be fascinating to watch and, if successful, could be a great basis for all of us to learn from.

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Stuttering Energy Transitions: Germany

2015 is knocking at the door. I just got The Economist’s “The World in 2015” special issue both in print and digital form. It’s full of numbers, predictions and stories. Most of its numbers and predictions are optimistic extrapolations of the present. The majority of the Science and Technology section includes information that is on the brink of public announcement. There also is a section by a science-fiction writer (Alastair Reynolds) that discusses which elements of fiction might soon become fact. The piece includes flying cars, talking to robots, new stuff from the Large Hadron Collider, etc., but it makes no predictions about what will happen to the planet as a whole. After all, there is no profit in trying to upset readers.

I will try to welcome 2015 a bit differently. On November 11th, the US and Chinese presidents came to a landmark agreement: the US will accelerate the speed of its current reduction of greenhouse gas emissions so that its level by 2025 will be close to 30% below its level in 2005 (double the pace of reduction it targeted for the period from 2005 to 2020). Meanwhile, China’s emissions will peak by 2030 – by which time sustainable sources should constitute at least 20% of its energy supply. People around the world saw this agreement by the two worst polluting countries as a good framework upon which to base a global agreement – one which will be discussed at the United Nations Climate Change Conference scheduled be held in Paris, France in December of 2015. Many eyes are now turning to India to see if it will follow. I will try to follow the global preparations for the December 2015 Paris meeting and include updates in this blog.

One of my main recurring themes on Climate Change Fork has been trying to follow the global energy transition from fossil fuels to a more sustainable mix. That mix must necessarily avoid changing the chemistry of the atmosphere, since any modification to the planetary energy balance could drastically affect the global climate. I have just ended a series of blogs (see all four November blogs) trying to make the case that such a transition is indeed possible, despite the many voices that disagree. Up to now I have discussed energy transition as a global phenomenon (see December 24, 2012 blog) with anecdotal references to individual countries. I think that it’s high time to change gear and address a few individual countries’ efforts in some more depth, as well as better defining the stuttering process that attempts at such transition entail. I have chosen six countries to follow, with the hope that their experiences can teach us all. These countries are China, US, India, Australia, France and Denmark. I have rearranged my computer’s filing system that is set to mimic my book’s chapter with updated information, to reflect on what takes place in these countries, in addition to (not instead of) the global picture. I plan to sustain my focus on the energy transitions that take place within these countries – at least until the Paris conference. That said, I fully expect that this focus will be interrupted frequently to reflect on important current events that I will wish to comment on.

I’ll start here with Germany and an article written by Justin Gillis in The New York Times. The article is focused on Germany’s energy transition and some of the important issues that it is raising. Below are some of the key paragraphs:

A reckoning is at hand, and nowhere is that clearer than in Germany. Even as the country sets records nearly every month for renewable power production, the changes have devastated its utility companies, whose profits from power generation have collapsed.

… Taking full advantage of the possibilities may require scrapping the old rules of electricity markets and starting over, industry observers say — perhaps with techniques like paying utilities extra to keep conventional power plants on standby for times when the wind is not blowing and the sun is not shining. The German government has acknowledged the need for new rules, though it has yet to figure out what they should be. A handful of American states are beginning a similar reconsideration of how their electric systems operate.

‘It’s pretty amazing what’s happening, really,’ said Gerard Reid, an Irish financier working in Berlin on German energy projects. ‘The Germans call it a transformation, but to me it’s a revolution.’

… The shifting economics can largely be traced to China, by way of Germany. Over the past decade, the Germans set out to lower the cost of going green by creating rapid growth in the once-tiny market for renewable power.

Germany has spent more than $140 billion on its program, dangling guaranteed returns for farmers, homeowners, businesses and local cooperatives willing to install solar panels, wind turbines, biogas plants and other sources of renewable energy. The plan is paid for through surcharges on electricity bills that cost the typical German family roughly $280 a year, though some of that has been offset as renewables have pushed down wholesale electricity prices.

… In Germany, where solar panels supply 7 percent of power and wind turbines about 10 percent, wholesale power prices have crashed during what were once the most profitable times of day. ‘We were late entering into the renewables market — possibly too late,’ Peter Terium, chief executive of the giant utility RWE, admitted this spring as he announced a $3.8 billion annual loss.

The big German utilities are warning — or pleading, perhaps — that the revolution cannot be allowed to go forward without them. And outside experts say they may have a point.

The Achilles’ heel of renewable power is that it is intermittent, so German utilities have had to dial their conventional power plants up and down rapidly to compensate. The plants are not necessarily profitable when operated this way, and the utilities have been threatening to shut down facilities that some analysts say the country needs as backup.

The situation is further complicated by the government’s determination to get rid of Germany’s nuclear power stations over the next decade, the culmination of a long battle that reached its peak after the 2011 Fukushima disaster in Japan. As that plan unfolds, shutting down a source of low-emission power, Germany’s notable success in cutting greenhouse gases has stalled.

So, what is happening in Germany? The German program for energy transition is summarized in a document titled “Energy Transition – the German Energiewende.”

The government-approved program objectives were set in 2010 and are summarized in figure 1. As the site mentions, the history of the program didn’t start with the present government or with the realization that an energy transition is needed to mitigate anthropogenic climate change. Instead, it started as an anti-nuclear effort, and has developed and gained public support throughout the years.  Government Approved Objectives of the German Energy Transition

Figure 1 – Government Approved Objectives of the German Energy Transition

According to German sources, the program enjoys wide public support (60%) but since there are winners and losers in the program, there is no shortage of public disagreements.

The distribution of primary energy resources, as of shortly after the adoption of the program, is summarized in figure 2.

Primary Energy Consumption in Germany - 2011

Figure 2 – Primary Energy Consumption in Germany – 2011

The program is evolving. As Justin Gillis mentioned in his article, the Fukushima nuclear disaster in Japan has left a serious mark on Germany’s policy makers. Shortly after the disaster, on May 29, 2011, Merkel’s government announced that it would close all of its nuclear power plants by 2022. Eight of the seventeen operating reactors in Germany were permanently shut down following Fukushima. Energy supply had to adjust, and coal and other fossil fuels have filled much of the gap.

On December 4th, the government announced the following adjustment:

BERLIN — Germany has fallen behind in its ambitious goals for reducing carbon emissions. It is burning more coal than at any point since 1990. And German companies are complaining that the nation’s energy policies are hurting their ability to compete globally.

But on Wednesday, Chancellor Angela Merkel’s government said it was redoubling its efforts, proposing new measures to help it reach the emissions-reduction target for 2020 it set seven years ago when it undertook an aggressive effort to combat climate change.

However, something else happened the same day, as reported in a piece by Paul Hockenos that appeared on “Renewable Energy World”:

BERLIN — Germany’s biggest utility E.ON — long a pillar of the country’s fossil fuel and nuclear industry — dropped a bombshell on Europe’s business world with the announcement that the multinational was exiting the conventional energy market in favor of a new business model based on renewables, intelligent grid systems, energy management and other services. Indeed, the company seems finally to have drawn the logical consequences from the Energiewende, Germany’s renewable energy transition, after years of resisting the ambitious transformation of the nation’s energy supply.

‘This is part of a transformation that almost all of Europe’s major utilities are currently undergoing in response to fundamental changes in their energy markets,’ says Toby Couture, director of the Berlin-based consulting firm E3 Analytics. ‘They’re endorsing different adaption strategies. E.ON’s seems to be the boldest, the most far-reaching so far.’

A few days later, an article in The Economist provided some more details:

FOR many Germans, E.ON, the country’s biggest utility, is a symbol of stability. But on November 30th it surprised by announcing it would split itself up. In 2016 it will float a new company which will include its power generation from nuclear and fossil fuels, as well as fossil-fuel exploration and production. The rump—which will keep the E.ON brand—will make money from renewable energy, distribution and ‘customer solutions’, a grab-bag of offerings such as advice, smart-metering and the like. The firm’s boss, Johannes Teyssen, said that as a sprawling integrated utility E.ON could only be ‘mediocre’. Two focused ones would do a much better job.

As Justin Gillis’ piece made clear, the majority of German utilities fought tooth and nail against the new program. In the next blogs I will try to explore the reasons for their opposition and the role of the intermittent nature of sustainable sources in the energy transition. Meanwhile, it is interesting to see that Germany’s largest utility is sort of switching sides by splitting not only its focus but also its entire organization.

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The Price of Wobbling

Thanksgiving is around the corner (at the time of writing – by the time this is posted it will be a few days after) and the semester is just about over. This time of the year the students are focusing on the finals. For the climate change course that I teach, my routine for the final exam is to have the students refute the arguments made by climate change deniers. I take the arguments from extensive deniers’ literature such as the list compiled by the Heartland Institute or that compiled by Skeptical Science. The students know that it’s challenging to make an effective argument. In a previous blog (March 25, 2014), which I posted toward the end of last semester, I wrote that my main goal is to improve their ability to argue. This is a continuing challenge.

A few weeks ago, an Op-Ed in the New York Times, titled “Wobbling on Climate Change” and written by Piers Sellers, brought me back to the issue in an important way. I didn’t respond in a timely way because I was busy until recently with the series of blogs on EROI (all four November blogs). Now is the time to return to this issue. I will start by quoting directly from the Op-Ed:

GREENBELT, Md. — I’M a climate scientist and a former astronaut. Not surprisingly, I have a deep respect for well-tested theories and facts. In the climate debate, these things have a way of getting blurred in political discussions.

In September, John P. Holdren, the head of the White House Office of Science and Technology Policy, was testifying to a congressional committee about climate change. Representative Steve Stockman, a Republican from Texas, recounted a visit he had made to NASA, where he asked what had ended the ice age:

‘And the lead scientist at NASA said this — he said that what ended the ice age was global wobbling. That’s what I was told. This is a lead scientist down in Maryland; you’re welcome to go down there and ask him the same thing.

‘So, and my second question, which I thought it was an intuitive question that should be followed up — is the wobbling of the earth included in any of your modelings? And the answer was no…

‘How can you take an element which you give the credit for the collapse of global freezing and into global warming but leave it out of your models?’

That ‘lead scientist at NASA’ was me. In July, Mr. Stockman spent a couple of hours at NASA’s Goddard Space Flight Center listening to presentations about earth science and climate change. The subject of ice ages came up. Mr. Stockman asked, ‘How can your models predict the climate when no one can tell me what causes the ice ages?’

I responded that, actually, the science community understood very well what takes the earth into and out of ice ages. A Serbian mathematician, Milutin Milankovitch, worked out the theory during the early years of the 20th century. He calculated by hand that variations in the earth’s tilt and the shape of its orbit around the sun start and end ice ages. I said that you could think of ice ages as resulting from wobbles in the earth’s tilt and orbit.

The time scales involved are on the order of tens of thousands to hundreds of thousands of years. I explained that this science has been well tested against the fossil record and is broadly accepted. I added that we don’t normally include these factors in 100-year climate projections because the effects are too tiny to be important on such a short time-scale.

And that, I thought, was that.

So I was bit surprised to read the exchange between Dr. Holdren and Representative Stockman, which suggested that at best we couldn’t explain the science and at worst we scientists are clueless about ice ages.

We aren’t. Nor are we clueless about what is happening to the climate, thanks in part to a small fleet of satellites that fly above our heads, measuring the pulse of the earth. Without them we would have no useful weather forecasts beyond a couple of days.

The question that Representative Stockman asked John Holdren, is a legitimate question related to climate change. The issue of how Earth got into and out of the ice ages and the nature of the Milankovitch cycles that explain it are standard topics in my course and in any other course that focuses on climate change. Representative Stockman’s question appears frequently on tests in these courses. If a student had given me the answer that John Holdren gave to Representative Stockman, I would have strongly suspected that he Googled it and only had enough time to read the first line or so. If student had asked me that question during class and I had given him this answer, the student would have rightly thought that I was being completely dismissive of him and probably would have used the first opportunity to drop my class.

Representative Stockman is more powerful than my students. He can actually be instrumental in the legislative efforts to either facilitate the mitigation of climate change or to erect obstacles to doing so. He doesn’t fit into any of the stereotypes of deniers (September 3, 2012) that I have previously discussed. He also feels strongly that he needs to educate himself in order to contribute to the legislative effort to face this issue. We need more policy makers like him.

If my students feel that I am denigrating them, their reactions are limited to trying to drop the course or trying to learn the answers to their questions on their own if they are strongly motivated. If a policy maker feels that he is being disparaged by a science adviser to the president (especially one that also happens to be among the top climate scientist in the country) his reaction can be much more destructive. Instead, in this instance, according to the Op-Ed, Representative Stockman was more productive. He used the response from Dr. Holdren to ask NASA scientists if they are using the wobbling in their present modeling to predict the long term impact of climate change. It took a bit of effort on his part to go through the hoops, and he ended up discussing the issue with Dr. Sellers to learn why the wobbling is not very relevant in the modeling of the climate through the end of the century.

Most policy makers are not that persistent. They are constantly subjected to various, often conflicting, pressures and are being asked to weigh the information given to them and to try to convert it into productive policy decisions.

On a different level, all voting-age citizens are being subjected to similar such multiple, often conflicting, pressures – we are charged with voting in a government whose priorities we agree with and voting out governments with which we disagree. This puts all of us into a position to be both teachers and students at the same time. To educate informed citizens is a major effort; to educate informed, important policy makers is an urgent task – one for which we pay a very dear price if we fail.

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Yes We Can 3: The Alcohol Debate

This will be the last in the series of blogs on EROI that started with John Morgan’s guest blog (November 4). The set of data in all three blogs was based on a paper by Weißbach et al. that suggested an economic threshold below which sustainable energy sources cannot be used in the substitution of fossil fuel, thus calling into question the whole issue of a feasible energy transition to non-carbon-based energy sources. One of these sustainable energy sources is biomass, as exemplified by ethanol (drinking alcohol) fermented from corn. Its EROI value (buffered or un-buffered), as put forward in the Weißbach paper, was 3.5 – well below the stated economic threshold. I have decided to focus this blog on the debate around this value, which started as soon as the United States legislated a requirement to include a statement of the amount of alcohol in all automotive fuels being sold within the country.

Some of the characteristics of the alcohol (biomass in the figure) are not obvious, but they are both interesting and important in the climate change debate. Many of the characteristics, once the details are explored, also shed considerable doubts (at least in my mind) on the main EROI issues that we discussed in the last three blogs.

Why is biomass among the assortment of sustainable energy sources?

The burning of ethanol generates 6,743Btu per 1Lb of emitted carbon dioxide, while the burning of natural gas generates 8,751Btu for the same amount of emitted carbon dioxide – these figures are not much different yet one is regarded as sustainable while the other is regarded as a polluting fossil fuel. The reason for this is that the designation refers to the full cycle of production and burning. The ethanol is fermented from a biological crop grown annually; as with all plants, the corn uses a solar-powered photosynthetic process that sequesters the carbon dioxide from the atmosphere. The burning process returns the same amount of carbon dioxide to the atmosphere while releasing the stored energy. That means over the full cycle, the energy used actually all comes from solar energy, and presents no changes to the chemistry of the atmosphere.

In the case of natural gas, a similar process takes place – except that fossil fuels were formed hundreds of millions of years ago from the decomposition of dead plants and animals. This time lag completely separates the sequestration process from the combustion process, thus making it unsustainable.

If the energy that we use in the combustion of biomass comes from solar energy why it is not considered an intermittent source of energy like the other solar energy forms (solar PV, wind, solar CSP and hydro) which require storage (the difference between the buffered and un-buffered in the graph)?

This is an excellent question with a somewhat hazy answer. The main reason is that in a place like the United States the alcohol is made mostly by fermenting (bacterial digestion of the sugar) corn. Corn is also used to feed people and animals. This forms a tight connection between the food supply and the energy supply. In a sense, the food supply acts as the storage component of the energy supply. Unfortunately, it creates major issues for the food supply, which are especially notable since the majority of the world’s population is much more dependent on food supply than those who live in rich, developed countries such as our own. This brings us back to ancient times and the biblical story of how Joseph got to such a high position in the Egyptian hierarchy because of his ability to regulate the intermittency of the seven bad years and seven good years (I previously explored this in the context of fresh water supply in my April 8, 2014 blog).

The idea of using ethanol as a partial replacement for fossil fuels didn’t start because of awareness of climate change. As I have mentioned before (October 29, 2012), soon after World War II, it became evident that dependence on fossil fuels as the main source of energy would have to end sooner or later (remember the Hubbert Peak theory). The main reasons at that time were our finite supply and the limited reliability of foreign suppliers. So the thought was that it would be great to be able to grow our energy supply. This move would be especially great for the agricultural sector, which would be charged with increasing supply, thus giving them leave to raise prices and increase their profits. There were fierce debates that took place on this issue, many of which focused on the EROI that was calculated for this new energy supply.

The debate started following some EROI measurements that showed that it takes more fossil fuels to produce the same amount of energy that can be extracted from the ethanol – in other words, it’s an EROI smaller than 1. In 2002 the US Department of Agriculture (USDA) took its own measurements and summarized them in a report on the topic.

I am quoting three short introductory paragraphs from the report and including a detailed table that summarizes the results:

Ethanol production in the United States grew from just a few million gallons in the mid-1970s to over 1.7 billion gallons in 2001, spurred by national energy security concerns, new Federal gasoline standards, and government incentives. Production of corn-ethanol is energy efficient, in that it yields 34 percent more energy than it takes to produce it, including growing the corn, harvesting it, transporting it, and distilling it into ethanol.

Growth in ethanol production has provided an economic stimulus for U.S. agriculture, because most ethanol is made from corn. The increase in ethanol demand has created a new market for corn, and agricultural policymakers see expansion of the ethanol industry as a way of increasing farm income and reducing farm program payments, while helping the U.S. economy decrease its dependence on imported oil. Increasing ethanol production induces a higher demand for corn and raises the average corn price. Higher corn prices can result in reduced farm program payments.

Today’s higher corn yields, lower energy use per unit of output in the fertilizer industry, and advances in fuel conversion technologies have greatly enhanced the energy efficiency of producing ethanol compared with just a decade ago. Studies using older data may tend to overestimate energy use because the efficiency of growing corn and converting it to ethanol has been improving significantly over time. The estimated net energy value (NEV) of corn ethanol was 21,105 Btu/gal under the following assumptions: fertilizers are produced by modern processing plants, corn is converted in modern processing facilities, farmers achieve normal corn yields, and energy credits are allocated to coproduces.

The table is long and detailed, but I think that it is crucial to gaining some understanding of the complexity and subjectivity involved in the calculations of a concept such as EROI before accepting claims that such calculations prove or disprove the viability of doing things that we regard as essential.

Ethanol EROI Big Table

Summary of abbreviations in the table: LHV-Low Heat Value, HHV – High Heat Value (the difference between LHV and HHV is often a source of confusion and it originates with exclusion or the inclusion of the water vaporization energy in the process; the difference amounts to about 10% in most cases), Bu – bushel, NR – not reported.

The debate started to have a wider audience after Congress passed the Renewable Fuel Standard (RFS) law in 2005. Here is how the EPA summarized this law and the mandated steps to be taken:

EPA is responsible for developing and implementing regulations to ensure that transportation fuel sold in the United States contains a minimum volume of renewable fuel. The Renewable Fuel Standard (RFS) program regulations were developed in collaboration with refiners, renewable fuel producers, and many other stakeholders.

The RFS program was created under the Energy Policy Act (EPAct) of 2005, and established the first renewable fuel volume mandate in the United States. As required under EPAct, the original RFS program (RFS1) required 7.5 billion gallons of renewable- fuel to be blended into gasoline by 2012.

Shortly after the law was passed (January 2006) a detailed article appeared in Science Magazine on the issue (“Ethanol Can Contribute to Energy and Environmental Goals”; Alexander E. Farrell,1* Richard J. Plevin,1 Brian T. Turner,1,2 Andrew D. Jones,1 Michael O’Hare,2 Daniel M. Kammen1,2,3 ; Science 311, 506 (2006)).

I am attaching the key figure from this article below.

Science Magazine Net GHG Ethanol Energy Graph

Net energy and net greenhouse gases for gasoline, six studies, and three cases. (B) Net energy and petroleum inputs for the same. In these figures, small light blue circles are reported data that incommensurate assumptions, whereas the large dark blue circles are adjusted values that use identical system boundaries. Conventional gasoline is shown with red stars, and EBAMM scenarios are shown with green squares…









A few months later (June 23, 2006 – Vol. 312) an extensive comments section which focused on the article appeared in the magazine. The comments included both the issue of the competition with the food supply that I mentioned earlier and EROI calculations. Farrell et al. calculated the EROI of ethanol from corn as 1.2. This value means that the use of ethanol as an energy source leaves a replacement value of about 20% for other uses of fossil fuels aside from running the production of ethanol. This value was in agreement with the value that the Department of Agriculture quoted earlier and remains the most quoted value until today. The value that was given in the Weißbach paper, on the other hand, is 3.5.

These two values are not the end of the story. If you google the term “ethanol fuel,” you will find a Wikipedia entry that provides us with the following table:Ethanol Energy Balance Mini Table

These values are taken from an October 2007 article in National Geographic (“Green Dreams: Making fuel from crops could be good for the planet—after a breakthrough or two”; Joel K. Bourne, Jr., Robert Clark; National Geographic Magazine October 2007 p. 41). Everybody now realizes that the future of biomass – both in terms of the EROI and its disconnect from the food – supply rests in fermentation from cellulosic ethanol, which is defined as “biofuel produced from wood, grasses, or the inedible parts of plants.”

In the meantime, the production of corn-based ethanol in the United States went from 6.4 billion gallons in 2007 to 13.9 billion gallons in 2011. Not surprisingly, attempts to adjust the requirements are being met with considerable difficulties.

In the meantime, Happy Thanksgiving – I appreciate your continued readership.

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Yes We Can 2: The Weißbach Paper

A few weeks ago, John Morgan wrote a guest blog here (November 4, 2014) called “The Catch-22 of Energy Storage and EROI.” My conversation with him started by way of a Twitter discussion of David MacKay’s paper on the long term storage requirements for any energy transition from fossil fuels to solar-based, more intermittent, sustainable sources such as wind and solar. The posting was heavily based on a recent paper written by a set of scientists, listed with D. Weißbach as the first author (Energy 52 (2013) 210). Because of the importance of the issues that Dr. Morgan raised, I promised to comment on the Weißbach paper directly in this blog.

With regards to the global energy transition that is necessary to mitigate anthropogenic (man-made) climate change, politics is often not far removed from the science. Germany is on the global forefront of the transition, but its efforts are not proceeding without an intense public debate. The issue of storage and the use of nuclear energy are in the forefront of the debate (see the excellent discussion on Germany’s efforts in this area in Justin Gillis’ article in the New York Times). All the authors of the Weißbach paper are affiliated with the Institut für Festkörper-Kernphysik, which translates to “The Institute for Solid-State Nuclear Physics,” however, said institute is part of an international group, which also includes scientists who are affiliated with Polish and Canadian institutions. The article was titled and authored as follows:

Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants

D. Weißbach a,b,*, G. Ruprecht a, A. Huke a,c, K. Czerski a,b, S. Gottlieb a, A. Hussein a,d
a Institut für Festkörper-Kernphysik gGmbH, Leistikowstraße 2, 14050 Berlin, Germany
b Instytut Fizyki, Wydział Matematyczno-Fizyczny, Uniwersytet Szczeci_nski, ul. Wielkopolska 15, 70-451 Szczecin, Poland
c Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
d Department of Physics, University of Northern British Columbia, 3333 University Way, Prince George, BC V6P 3S6, Canada

The article does not confine itself to storage, but also deals with the generation of electric power based on the EROI (Energy Return on Investment) – the ratio of the energy delivered by a process to the energy used directly and indirectly to fuel that process. Here is how the article starts:

The economic efficiency and wealth of a society strongly depend on the best choice of energy supply techniques which involves many parameters of quite different significance. The “energy returned on invested”, EROI (often also called ERoEI), is the most important parameter as it describes the overall life-cycle efficiency of a power supply technique, independent from temporary economical fluctuations or politically motivated influence distorting the perception of the real proportions. The EROI answers the simple question “How much useful energy do we obtain for a certain effort to make this energy available” (the terms “effort”, “useful”, and available will be specified below).

Both Dr. Morgan’s guest blog and my own the following week presented the end results in the form of the same graph, but for the sake of convenience, I will show it again here:

Buffered - Unbuffered EROIIn last week’s blog I quoted the Weißbach paper as to the origin of the economic threshold to show that it has nothing to do with physics but is instead based on economic criteria. The paragraph below describes the origin of their data. They came from LCA analysis, and as the article mentions, they are controversial.

In this work, based on several LCA (life cycle assessments) studies, EROIs will be calculated by using a strictly consistent physical definition thus making the energy producing techniques comparable to each other. Energy input with the highest quality difference, i.e. thermal energy and electricity, are listed separately (given in percentage electrical of the total energy input), so the factor of interest, either the EROI or the EMROI can easily be determined and compared.

For the purpose of deciding which energy sources are suitable for global energy transition as replacement for reliance on fossil fuels, reliance on LCA has serious problems. The problems can be summarizes in terms of two main drawbacks:

  1. The necessity to draw subjective boundaries to define the scope of the analysis
  2. Great dependence on the particular set of technologies that are in use.

The two main inventories that are included in most analyses are energy and water. Both inventories suffer from the same broad range of values as measured in different facilities. I just recently returned from a conference in Iceland in which I presented our work on water stress (“The Many Faces of Water Use” by Gurasees Chawla and Micha Tomkiewicz; 6th International Conference on Climate Change, Reykjavik, Iceland (2014)). One of the issues that we discussed there was the concept of virtual water:  the “sum of the water footprints of the process steps taken to produce the product” – an idea that constitutes part of the LCA analysis of products. For instance, the typical virtual water of fruits is 1,000 m3/ton. To remind us all, the weight of pure water in these units is 1ton/1m3, so the weight of the virtual water is 1,000 times the weight of the product itself. Where did the extra water go? For the most part, it either became waste water or evaporated.

Yes they are blaming the US for the depletion of Mexican water but  in fact they should blame themselves because they are subsiding the Mexican strawberries growers by not charging them anything for the water that they use so that they will be able to better compete  against the American growers.

Here’s one example of the concept of virtual water, as given in an article in a Mexican science magazine: when the US imports strawberries from Mexico, the imported strawberries conceptually “carry” with them all the virtual fresh water that is so greatly needed in both countries (Camps, Salvador Penische and Patricia Ávila García, Revista Mexicana de Ciencias 3:1579 (2012)); this equates to the US “stealing” water from the Mexicans. As a result, some are blaming the US for the depletion of Mexican water, and charging our country with immoral economic capitalism.

Meanwhile when proper water management is being used (mainly waste water treatment), the virtual water can be reduced by 90%.

Let’s get back to energy storage with this section from the Weißbach paper:

4. Usable energy, storage, and over-capacities

Power systems provide exergy (electricity), but they must do it when this exergy is required, the second quality factor of usability. For the energy output, although the term “available” is easy to implement by defining the connection point to the network (as done here) or to the consumer, the term “usable” is more complicated. It implies that the consumer has an actual need for the energy at the moment it is available. It also means the opposite, that energy is available when the consumer needs it. There are only three possibilities to make the energy output fit the demand.

  • Ignoring output peaks and installing multiple times of the necessary capacity as a backup to overcome weak output periods.
  •  Installing storage capacities to store the peaks, with reduced over-capacity plant installations (short: buffering).
  • Adapting the demand to the output at all times.

The third point is obviously not acceptable, because one becomes dependent on random natural events (wind and PV solar energy). A developed and wealthy economy needs predictably produced energy every time, especially the industry needs a reliable base-load-ready output to produce high quality goods economically. So only the first two points are acceptable, whereof the second one is the economically most promising. Some energy generation techniques need more buffering (wind energy, photovoltaics), some less (solar CSP (concentrating solar power) in deserts, hydro power) and the fuel based ones almost no buffering (the fuel is already the storage). Technologically, this can only be solved by storage systems and over-capacities which are therefore inside the system borders, “replacing” the flexible usage of mined fuel by fuel-based techniques. In opposite to that, the IEA (International Energy Agency) advises to consider the backup outside the system borders without any scientific justification [6].

There is no argument that synchronization of electricity supply and demand is required – and not only with use of intermittent, sustainable sources such as wind and solar. Synchronization is also is required now to adjust for the peak and trough in use, but it is considerably smaller than the need with intermittent resources. However, the use of batteries is not the only option. Similar to proper water management, movement of electrical power from places of excess capacity to places of excess need by the use of smart grids, is an important option. In addition, many places combine different forms of energy, with different variability, to adjust for the intermittency of the sources. There is no question that these options reduce the EROI as well. By how much – I have no idea. Similarly to the water management case, it will depend critically on the boundaries set in the modeling.

This posting is getting to be too long. I will finish off with two short comments on the actual EROI calculations and expand in the next blog on the biomass calculations that demonstrate the close correlation between the science and politics.

As to limiting the analysis of photovoltaics to Silicon, here is the quote from the Weißbach article:

7.2. Solar photovoltaics (PV)

So far, only Silicon (Si) based PV technologies are applicable on a large scale, so only those have been evaluated here. CIGS- or CdTe based cells are no option since there is not even a fraction of the needed Indium or Tellurium available in the Earth crust and organic cells are still far from technical applications

We obviously cannot cover the planet with enough CIGS (Copper Indium Gallium Selenide) or CdTe to satisfy our energy needs, but they can and will be part of the spectrum of technologies that we use to replace fossil fuels. Si based cells are currently the overwhelming majority of active devices but once we are raising “in principle” arguments to stop development of alternative energy sources, we’d better be as inclusive as possible.

Looking at the figure above, the only two viable alternatives to fossil fuels are nuclear and hydro. The number of hydroelectric sites available is quickly diminishing, however, which leaves us with nuclear energy. Germany recently reacted to the 2011 Fukushima nuclear plant’s meltdown by completely discontinuing development of nuclear power, and it is far from the first time people have expressed fear of the energy source’s possible repercussions. So nuclear power might have other issues beside EROI. As seen from the graph above, the Weißbach paper lists nuclear power as having the highest value of EROI. The scientific community is full of literature arguing other opinions. A paper in Scientific American that summarizes EROI literature data (Mason Inman. April 2013) illustrates the discrepancy regarding nuclear energy – from values smaller than 1 (not an energy source) to the cited EROI to be between 40-60 for centrifuge-enriched uranium. Wikipedia, in its piece about EROI, gives the value for nuclear energy to be 10 for a diffusion-enriched plant (reference not provided). All of this provides enough information to show us more research is needed on the EROI of future energy sources. What it certainly does not do is guarantee with full security that we can currently predict the unique energy mix that will be necessary to displace or replace the use of fossil fuels.

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Yes We Can! :(

Obama - Yes We CanYesterday (November 4th) was Election Day in the US. It ended in a big victory for the Republicans, with a matching defeat for the Democrats and President Obama. It will be much more difficult for the President to push an agenda that he believes in through a Republican dominated Congress, and legislation to mitigate climate change will probably be a major casualty. The bright side of this is that the American democracy is solid enough that in two years the prevailing voices might change, and within the time span of climate change, two years is not a long time.

Parallel to that development, on the same date, Dr. John Morgan posted a guest blog here titled “The Catch-22 of Energy Storage and EROI,” which presented a much more serious obstacle to mitigating climate change. Below I have copied the graph and a few paragraphs from last week to highlight his discussion:

Buffered - Unbuffered EROI

Several recent analyses of the inputs to our energy systems indicate that, against expectations, energy storage cannot solve the problem of intermittency of wind or solar power.  Not for reasons of technical performance, cost, or storage capacity, but for something more intractable: there is not enough surplus energy left over after construction of the generators and the storage system to power our present civilization.

The problem is analysed in an important paper by Weißbach et al.1 in terms of energy returned on energy invested, or EROI (sometimes EROEI) – the ratio of the energy produced over the life of a power plant to the energy that was required to build it.  It takes energy to make a power plant – to manufacture its components, mine the fuel, and so on.  The power plant needs to make at least this much energy to break even.  A break-even power plant has an EROI of 1.  But such a plant would pointless, as there is no energy surplus to do the useful things we use energy for.

Anybody with a similar educational background to myself and Dr. Morgan (both of us have PhDs in Physical Chemistry as well as experience in energy research) sees a graph such as the one shown above as a likely consequence of the 2nd law of thermodynamics, since it features a threshold which you are not allowed to cross (see Adrian Cho’s comment on inequality in economics regarding my September 2, 2014 blog, and my October 8, 2013 blog on desalination). If you grow up in science, you know that you physically can’t defy the 2nd law of thermodynamics. That’s the law that is responsible for the 30% efficiency rate for generating electricity from fossil fuels, and it mandates the energy threshold necessary for desalinating water (October 8, 2013 blog).

Trends in Global Energy Use - Baseline & MitigationIf we are forbidden from crossing the threshold, however, we are left with only hydroelectric and nuclear means to replace fossil fuels or to capture the emissions from fossil fuel-powered devices (CCS – Capturing Carbon Dioxide and Sequestration). CCS drastically changes the economy and the EROI. As shown by Fig. 2 above, the IPCC recently published a typical energy scenario needed to achieve a stable atmosphere and a climate system that is not dominated by human activities. Basically, toward the end of the century, the only surviving fossil fuel without CCS will be natural gas. The rest of the slack would have to be picked up by nuclear energy and all the sustainable sources whose energy production the EROI argument claims are unachievable on such a scale.

This attitude fits perfectly with one of the shades of deniers that I have previously described – the skeptics (September 3, 2012 blog) and requires a detailed response that will follow in this and the next few blogs.

EROI has been very useful (and controversial) in the past in analyzing energy options to replace fossil fuels. The specific system that was the focus was using alcohol (ethanol) generated from corn as compared with the Brazilian use of sugar cane as the source. I will elaborate on this in my next blog. Here I will only mention that the argument focused on the fact that to make the ethanol we use energy that is largely generated from fossil fuels so if the EROI is too small we don’t replace (much less surpass) that expended from the fossil fuels. It would have been a different case if instead we were to grow the corn and use the product of the fermentation as our sole energy source to produce the alcohol. We obviously couldn’t have done it with an EROI smaller than 1; the break-even (EROI = 1) assures that there is enough energy supply to run the process and whatever is left afterwards will be available for other uses.

The emphasis on what you cannot do is problematic unless anchored on very strong arguments consistent with the science. In the place where I grew up, people are nice to their guests; I will not attack Dr. Morgan’s guest blog, but I do feel free to criticize the underlying paper on which his blog is based. The title of the threshold is the “Economic Threshold.” But it is also written that the EROI considerations are independent of economic considerations, meaning that the argument must be completely basic and fundamental – to me that says it must be as fundamental as the 2nd law. So let us go to the original paper: “Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants”; D. Weißbach a,b,*, G. Ruprecht a, A. Huke a,c, K. Czerski a,b, S. Gottlieb a, A. Hussein a,d;  Energy 52 (2013) 210e221 ).

6. Economical aspects

Since the “investor’s view” has been used whenever possible there should be a simple relation to the economy. In fact, the EMROIRem as defined in Sec. 2.5, is supposed to describe the economic relation better, even though it depends not only on the kind of the power plant but also on the surrounding market. Rem is used by many authors as “EROI”, but in fact it is somewhere in the middle of the physical EROI and the actual cost ratio as it still ignores human labor costs. Energetically, human labor is negligible but financially, it dominates and represents the welfare of the society or of the sub-society working in this energy sector. For the returned energy ER, the money to energy ratio is simply given by the usual market price. For the invested energy EI, however, the ratio is much larger since it contains all the surplus of the value-added chain. Therefore, an EROI threshold can be roughly estimated by the ratio of the GDP to the unweighted final energy consumption while an EMROI threshold can be estimated by the weighted final energy consumption (which is not the primary energy consumption). For the U.S., for instance, the GDP was $15 trillion in 2011 while the unweighted end energy consumption was about 20 trillion kWh, resulting in an “energy value” of some 70 cent/kWh (Germany w135 cent/kWh). The average electricity price, however, is 10 cent/kWh [10], (Germany w18 cent/kWh) so there is a factor of 7 higher money to energy ratio on the input side. The same calculation for the weighted final energy consumption (the electricity demand was multiplied by a factor of about 3) results in a ratio of about 16 for both countries, assuming average primary energy costs of 5 cent/kWh and 3.5 cent/kWh for Germany and the USA, respectively. A similar ratio can be seen for other countries which leads to the conclusion that the thresholds are 7 and 16 for the EROI and the EMROI, respectively, assuming OECD-like energy consuming technology. For lower developed countries thresholds might be smaller, thus making also “simple” energies like biomass economic. Of course, the cost structure for different power plants is quite different. For construction and maintenance of a nuclear power plant there are a lot of non-energetic costs, dominated by prolonged licensing procedures and highly-qualified personnel costs that can not be “outsourced”, contrary to solar cell production which profits from cheap manpower for manufacturing, e.g. in China. Besides ethical complications the monetary ratio can fluctuate anyway due to changing safety policies, international trading agreements and politically motivated subsidies. In summary, one has to consider both the EROI and the technical grade of energy consuming infrastructure (non-technical issues are ignored for simplicity here) to assess the society’s prosperity.

In other words, the threshold is not computed through physics; it is based on economics and what we are willing to do. What a relief! Next week I’ll analyze the Weißbach paper in a bit more detail and will try to show that Yes We Can save the planet for our children by changing the energy sources that we currently use.

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Guest Blog: John Morgan: The Catch-22 of Energy Storage and EROI

As I mentioned in my blog on October 21st, I have invited John Morgan to post a guest blog about EROI. This week, he has generously agreed to re-post the article that I mentioned, with an added postscript addressing questions that arose from its original publication. I welcome questions and comments, and plan to continue this conversation in next week’s post.


John Morgan is Chief Scientist at a Sydney startup developing smart grid and grid scale energy storage technologies.  He is Adjunct Professor in the School of Electrical and Computer Engineering at RMIT, holds a PhD in Physical Chemistry, and is an experienced industrial R&D leader.  You can follow John on twitter at @JohnDPMorgan.

The following article was first published in Chemistry in Australia.

The Catch-22 of Energy Storage


Pick up a research paper on battery technology, fuel cells, energy storage technologies or any of the advanced materials science used in these fields, and you will likely find somewhere in the introductory paragraphs a throwaway line about its application to the storage of renewable energy.  Energy storage makes sense for enabling a transition away from fossil fuels to more intermittent sources like wind and solar, and the storage problem presents a meaningful challenge for chemists and materials scientists.

Or does it?  Several recent analyses of the inputs to our energy systems indicate that, against expectations, energy storage cannot solve the problem of intermittency of wind or solar power.  Not for reasons of technical performance, cost, or storage capacity, but for something more intractable: there is not enough surplus energy left over after construction of the generators and the storage system to power our present civilization.

The problem is analysed in an important paper by Weißbach et al.1 in terms of energy returned on energy invested, or EROI (sometimes EROEI) – the ratio of the energy produced over the life of a power plant to the energy that was required to build it.  It takes energy to make a power plant – to manufacture its components, mine the fuel, and so on.  The power plant needs to make at least this much energy to break even.  A break-even powerplant has an EROI of 1.  But such a plant would pointless, as there is no energy surplus to do the useful things we use energy for.

There is a minimum EROI, greater than 1, that is required for an energy source to be able to run society.  An energy system must produce a surplus large enough to sustain things like food production, hospitals, and universities to train the engineers to build the plant, transport, construction, and all the elements of the civilization in which it is embedded.

For countries like the US and Germany, Weißbach et al. estimate this minimum viable EROI to be about 7.  An energy source with lower EROI cannot sustain a society at those levels of complexity, structured along similar lines.  If we are to transform our energy system, in particular to one without climate impacts, we need to pay close attention to the EROI of the end result.

The EROI values for various electrical power plants are summarized in the figure.  The fossil fuel power sources we’re most accustomed to have a high EROI of about 30, well above the minimum requirement.  Wind power at 16, and concentrating solar power (CSP, or solar thermal power) at 19, are lower, but the energy surplus is still sufficient, in principle, to sustain a developed industrial society.  Biomass, and solar photovoltaic (at least in Germany), however, cannot.  With an EROI of only 3.9 and 3.5 respectively, these power sources cannot support with their energy alone both their own fabrication and the societal services we use energy for in a first world country.

Buffered & Unbuffered EROIs

Energy Returned on Invested, from Weißbach et al.,1 with and without energy storage (buffering). CCGT is closed-cycle gas turbine. PWR is a Pressurized Water (conventional nuclear) Reactor. Energy sources must exceed the “economic threshold”, of about 7, to yield the surplus energy required to support an OECD level society.

These EROI values are for energy directly delivered (the “unbuffered” values in the figure).  But things change if we need to store energy.  If we were to store energy in, say, batteries, we must invest energy in mining the materials and manufacturing those batteries.  So a larger energy investment is required, and the EROI consequently drops.

Weißbach et al. calculated the EROIs assuming pumped hydroelectric energy storage.  This is the least energy intensive storage technology.  The energy input is mostly earthmoving and construction.  It’s a conservative basis for the calculation; chemical storage systems requiring large quantities of refined specialty materials would be much more energy intensive.  Carbajales-Dale et al.2 cite data asserting batteries are about ten times more energy intensive than pumped hydro storage.

Adding storage greatly reduces the EROI (the “buffered” values in the figure).  Wind “firmed” with storage, with an EROI of 3.9, joins solar PV and biomass as an unviable energy source.  CSP becomes marginal (EROI ~9) with pumped storage, so is probably not viable with molten salt thermal storage.  The EROI of solar PV with pumped hydro storage drops to 1.6, barely above breakeven, and with battery storage is likely in energy deficit.

This is a rather unsettling conclusion if we are looking to renewable energy for a transition to a low carbon energy system: we cannot use energy storage to overcome the variability of solar and wind power.

In particular, we can’t use batteries or chemical energy storage systems, as they would lead to much worse figures than those presented by Weißbach et al.  Hydroelectricity is the only renewable power source that is unambiguously viable.  However, hydroelectric capacity is not readily scaled up as it is restricted by suitable geography, a constraint that also applies to pumped hydro storage.

This particular study does not stand alone.  Closer to home, Springer have just published a monograph, Energy in Australia,3 which contains an extended discussion of energy systems with a particular focus on EROI analysis, and draws similar conclusions to Weißbach.  Another study by a group at Stanford2 is more optimistic, ruling out storage for most forms of solar, but suggesting it is viable for wind.  However, this viability is judged only on achieving an energy surplus (EROI>1), not sustaining society (EROI~7), and excludes the round trip energy losses in storage, finite cycle life, and the energetic cost of replacement of storage.  Were these included, wind would certainly fall below the sustainability threshold.

It’s important to understand the nature of this EROI limit.  This is not a question of inadequate storage capacity – we can’t just buy or make more storage to make it work.  It’s not a question of energy losses during charge and discharge, or the number of cycles a battery can deliver.  We can’t look to new materials or technological advances, because the limits at the leading edge are those of earthmoving and civil engineering.  The problem can’t be addressed through market support mechanisms, carbon pricing, or cost reductions.  This is a fundamental energetic limit that will likely only shift if we find less materially intensive methods for dam construction.

This is not to say wind and solar have no role to play.  They can expand within a fossil fuel system, reducing overall emissions.  But without storage the amount we can integrate in the grid is greatly limited by the stochastically variable output.  We could, perhaps, build out a generation of solar and wind and storage at high penetration.  But we would be doing so on an endowment of fossil fuel net energy, which is not sustainable.  Without storage, we could smooth out variability by building redundant generator capacity over large distances.  But the additional infrastructure also forces the EROI down to unviable levels.  The best way to think about wind and solar is that they can reduce the emissions of fossil fuels, but they cannot eliminate them.  They offer mitigation, but not replacement.

Nor is this to say there is no value in energy storage.  Battery systems in electric vehicles clearly offer potential to reduce dependency on, and emissions from, oil (provided the energy is sourced from clean power).  Rooftop solar power combined with four hours of battery storage can usefully timeshift peak electricity demand,3 reducing the need for peaking power plants and grid expansion.  And battery technology advances make possible many of our recently indispensable consumer electronics.  But what storage can’t do is enable significant replacement of fossil fuels by renewable energy.

If we want to cut emissions and replace fossil fuels, it can be done, and the solution is to be found in the upper right of the figure.  France and Ontario, two modern, advanced societies, have all but eliminated fossil fuels from their electricity grids, which they have built from the high EROI sources of hydroelectricity and nuclear power.  Ontario in particular recently burnt its last tonne of coal, and each jurisdiction uses just a few percent of gas fired power.  This is a proven path to a decarbonized electricity grid.

But the idea that advances in energy storage will enable renewable energy is a chimera – the Catch-22 is that in overcoming intermittency by adding storage, the net energy is reduced below the level required to sustain our present civilization.


When this article was published in CiA some readers had difficulty with the idea of a minimum societal EROI.  Why can’t we make do with any positive energy surplus, if we just build more plant?  Hall4 breaks it down with the example of oil:

Think of a society dependent upon one resource: its domestic oil. If the EROI for this oil was 1.1:1 then one could pump the oil out of the ground and look at it. If it were 1.2:1 you could also refine it and look at it, 1.3:1 also distribute it to where you want to use it but all you could do is look at it. Hall et al. 2008 examined the EROI required to actually run a truck and found that if the energy included was enough to build and maintain the truck and the roads and bridges required to use it, one would need at least a 3:1 EROI at the wellhead.

Now if you wanted to put something in the truck, say some grain, and deliver it, that would require an EROI of, say, 5:1 to grow the grain. If you wanted to include depreciation on the oil field worker, the refinery worker, the truck driver and the farmer you would need an EROI of say 7 or 8:1 to support their families. If the children were to be educated you would need perhaps 9 or 10:1, have health care 12:1, have arts in their life maybe 14:1, and so on. Obviously to have a modern civilization one needs not simply surplus energy but lots of it, and that requires either a high EROI or a massive source of moderate EROI fuels.

The point is illustrated in the EROI pyramid.4 (The blue values are published values: the yellow values are increasingly speculative.)

Society's Heirarchy of Energetic NeedsFinally, if you are interested in pumped hydro storage, a previous Brave New Climate article by Peter Lang covers the topic in detail, and the comment stream is an amazing resource on the operational characteristics and limits of this means of energy storage.

  1. Weißbach et al., Energy 52 (2013) 210. Preprint available here.
  2. Carbajales-Dale et al., Energy Environ. Sci. DOI: 10.1039/c3ee42125b
  3. Graham Palmer, Energy in Australia: Peak Oil, Solar Power, and Asia’s Economic Growth; Springer 2014.
  4. Pedro Prieto and Charles Hall, Spain’s Photovoltaic Revolution, Springer 2013.
Breakout Box: Origins of EROI
The concept of EROI was introduced by US fisheries ecologist Charles Hall, who noted that the energy a predator gained from eating prey had to exceed the energy expended in catching it. In 1981, Hall applied this net energy analysis to our own power generation activities, charting the decline of the EROI of US oil as ever more drilling was required to yield a given quantity, and suggesting the possibility that oil may one day take more energy to extract than it yields. Hall and others have since estimated the EROI for various power sources, a difficult analysis that requires identification of all energy inputs to power production.
EROI is a fundamental thermodynamic metric on power generation. Net energy analysis affords high-level insights that may not be evident from looking at factors such as energy costs, technological development, efficiency and fuel reserves, and sets real bounds on future energy pathways. It is unfortunately largely absent from energy and climate policy development.
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Back to Sustainable Energy Transition: Scenarios and Progress

The IPCC’s original charge is as follows:

The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for the assessment of climate change. It was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988 to provide the world with a clear scientific view on the current state of knowledge in climate change and its potential environmental and socio-economic impacts. In the same year, the UN General Assembly endorsed the action by WMO and UNEP in jointly establishing the IPCC.

The IPCC is a scientific body under the auspices of the United Nations (UN). It reviews and assesses the most recent scientific, technical and socio-economic information produced worldwide relevant to the understanding of climate change. It does not conduct any research nor does it monitor climate related data or parameters.

As the section above states, the IPCC does not do any research of its own. It is charged with reviewing and assessing ongoing research. It is also a very strong advocacy organization that is trying to influence policy makers to agree on policies that will prevent future global environmental disaster in the form of climate change. The first requirement for persuading somebody, though, is to have them actually read what you write. Right now, I strongly suspect (though I have no express evidence) that very few policy makers read what the IPCC writes directly. Instead, most policy makers, along with the general public, get their information about the IPCC’s findings as filtered through intermediaries such as press reports. The press, in turn, only presents a few very short highlights; this is only one of the vast number of news issues it covers. The IPCC’s data is in direct competition with all of the other sources of information. This mode of information distribution makes it relatively easy for people (deniers!) presenting counter-arguments to make their voices heard loudly, no matter how solid the science is supporting anthropogenic (man-made) climate change. This continues to be the case, in spite of the fact that the IPCC reports include specific chapters directed at “policy makers.” In fact, very few policy makers can follow these chapters (see my October 14, 2014 blog). One big factor is the way that the IPCC presents the future: in terms of scenarios.

I showed this graph in my last two blogs, and am including it again here. It was one of the main highlights of the latest IPCC report; it describes the historical and projected global average surface temperature changes.

IPCC Global average surface temperature change

In its August 14th report, Skeptical Science gave a simplified description of the various IPCC scenarios (again with the intermediaries!). Here is a key section:

Why are scenarios necessary?

“Scenarios of different rates and magnitudes of climate change provide a basis for assessing the risk of crossing identifiable thresholds in both physical change and impacts on biological and human systems.”

Source: “Towards New Scenarios for Analysis of Emissions, Climate Change, Impacts, and Response Strategies”, IPCC Technical Summary, 2007

There are many climate modelling teams around the world. If they all used different metrics, made different assumptions about baselines and starting points, then it would be very difficult to compare one study to another. In the same way, models could not be validated against other different, independent models, and communication between climate modelling groups would be made more complex and time-consuming.

Another problem is the cost of running models. The powerful computers required are in short supply and great demand. Simulation programming that had to start from scratch for each experiment would be wholly impractical. Scenarios provide a framework by which the process of building experiments can be streamlined.

In order to address these issues, in 1992 the Intergovernmental Panel on Climate Change (IPCC) published the first set of climate change scenarios, called IS92. In year 2000 the IPCC released a second generation of projections, collectively referred to as the Special Report on Emissions Scenarios (SRES). These were used in two subsequent reports; the Third Assessment Report (TAR) and Assessment Report Four (AR4) and have provided common reference points for a great deal of climate science research in the last decade.

In 2007, the IPCC responded to calls for improvements to SRES by catalysing the process that produced the Representative Concentration Pathways (RCPs). The RCPs are the latest iteration of the scenario process, and are used in the next IPCC report – Assessment Report Five (AR5) in preference to SRES.

The changes from the SRES to the RCP scenarios in the last report were introduced mainly for the benefits of scientists, to make “reviewing and assessing” easier. In the process, SRES scenarios’ close connections with socioeconomic changes got lost in favor of a focus on the net impact on greenhouse gas emissions. Meanwhile, the number of evaluated scenarios changed: in both the SRES and the RCPs, there were four families, but the SRES included 40 scenarios, whereas the RCPs are defined in terms of only four different emission scenarios.

In terms of the above RCP8.5 scenario, which depicts an everlasting increase in temperature, the new focus makes very little difference. It basically shows the “business as usual” scenario or, using the new terminology: the “background scenario.” In all presentations, this is the scenario that we all start with; one extrapolated from a future with no change in the rates of growth, or the associated emissions.

The big difference is in showing how we are trying to get to where we want to be – the “environmentally stable” RCP2.6 scenario. The authors in the journal “Climatic Change” (November 2011, Volume 109, Issue 1-2,) give a detailed account of the considerations behind this scenario. The SRES and RCP scenario families are both “what ifs” based on plugging possible socioeconomic inputs into computers to calculate greenhouse gas emission consequences. The SRES scenario family represents passive scenarios, while the RCP family is constructed to include mitigation policies. It is obvious that the RCP2.6 requires much stronger mitigation policies compared to RCP8.5, which describes what will happen if we continue what we are doing now. To have any effect, mitigation policies require global agreement, and that is very hard to come by – especially now. In spite of the difficulties, there is continuing global progress to close the gap between the two scenarios. Future blogs will try to go into some details of what must take place to narrow the gap.

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Back to the Sustainable Energy Transition: The Physics of Sustainability and Some Tweets About it.

In the last blog I strongly advocated simplifying the conversation about climate change, focusing on how we can get from the present “business as usual” scenario to an “environmentally friendly” scenario that will not result in an environment inhospitable to adaptation. The recent IPCC report summarized the difference between the two scenarios with this graph, which I also showed last week:

IPCC Global average surface temperature changeI will elaborate on the two scenarios and their implications in future blogs.

Meanwhile, I would like to highlight some recent activities that have been occupying my time and which I hope might help clarify the process of changing from scenario one to the other. Let’s start with two events:

  1. I was invited by the editors of a new journal of the Material Research Society (MRS), which focuses on energy and sustainability, to write a review article entitled “Energy and Sustainability, from the point of view of Environmental Physics.” The title was suggested by one of the journal’s editors, and I make a point not to argue with editors. However, I am free to interpret the title as I see fit and set the boundaries of the article. I will start by using my previous definition (January 28, 2013 blog): I define sustainability as the condition that we have to develop here to flourish until we can develop the technology for extraterrestrial travel that will allow us to move to another planet once we ruin our own.” In principle, a scenario such as the RCP2.6 scenario, is supposed to get us there. I’ll be writing the article over the next two months, hopefully focusing on the challenges that face material research scientists as they struggle to develop materials that will help to take us from the present “business as usual” scenario to the RCP2.6 scenario.
  1. The second event developed out of a request that I got over Twitter to write something about a new article by David MacKay, where he discussed the storage requirements of such a transition. I liked the paper and summarized my response in a short blog that I posted here on August 8th.

There was a small buzz over that response, which I am including below.

John Morgan @JohnDPMorgan  Aug 11
@MichaTomkiewicz @nuclear94 Cost and capacity are not the issue. EROI of renewables are degraded below viable level by storage.

 Jeff Terry ‏@nuclear94 Aug 11
@JohnDPMorgan @sydnets @MichaTomkiewicz capacity is an issue. No one knows how to store and extract energy of that magnitude.

 Jeff Terry ‏@nuclear94 Aug 11
@JohnDPMorgan @sydnets @MichaTomkiewicz 36 TWhr of storage is 9x annual output of Hoover Dam. Good luck with that.

@nuclear94 @sydnets @MichaTomkiewicz What @JohnDPMorgan said was that capacity is not *the* issue, not that it isn’t an issue.

Ben McCombe ‏@BenMcCombe Aug 11
@nuclear94 @sydnets @MichaTomkiewicz @JohnDPMorgan If EROI issue can’t be resolved, then storage is a no go whatever the capacity.

Jeff Terry ‏@nuclear94 Aug 11
@BenMcCombe @sydnets @MichaTomkiewicz @JohnDPMorgan assuming one’s survival does not depend upon it.

John Morgan ‏@JohnDPMorgan 19h
@BenMcCombe @nuclear94 @sydnets @MichaTomkiewicz Ben’s reading is correct. The EROI problem is intractable, even if we had free TWh capacity

Jeff Terry ‏@nuclear94 19h
@JohnDPMorgan @BenMcCombe @sydnets @MichaTomkiewicz depends upon how bad the problem gets.

Dadiva Netter ‏@sydnets 19h
@nuclear94 @JohnDPMorgan @BenMcCombe @MichaTomkiewicz could further innovation make a difference?

John Morgan ‏@JohnDPMorgan 19h
@nuclear94 @BenMcCombe @sydnets @MichaTomkiewicz Solar, wind + storage is either in energy deficit, or too low positive to work. Pretty bad.

John Morgan ‏@JohnDPMorgan 19h
@sydnets @nuclear94 @BenMcCombe @MichaTomkiewicz I don’t think so. The leading edge of storage EROI is earthmoving.

Jeff Terry ‏@nuclear94 19h
@sydnets @JohnDPMorgan @BenMcCombe @MichaTomkiewicz miracles can always make a difference.

Jeff Terry ‏@nuclear94 17h
@MichaTomkiewicz @sydnets @JohnDPMorgan @BenMcCombe the energy density is still not there.

John Morgan ‏@JohnDPMorgan 15h
@MichaTomkiewicz @nuclear94 @sydnets @BenMcCombe There is no storage tech that can store wind or solar energy at adequate system EROI.

John Morgan ‏@JohnDPMorgan 15h
@MichaTomkiewicz @nuclear94 @sydnets @BenMcCombe Nothing on the horizon, either.

John Morgan ‏@JohnDPMorgan 15h
Throwing our limited resources at incapable tech is the functional
equivalent to giving up. @MichaTomkiewicz @nuclear94 @sydnets @BenMcCombe

John Morgan ‏@JohnDPMorgan 15h
“Not giving up” just means shifting our efforts to directions that can yield
results. @MichaTomkiewicz @nuclear94 @sydnets @BenMcCombe

Twitter responses are by their nature short, but a collection of them can be relevant and informative. EROI (Energy Return on Energy Invested) is an important concept that was brought up several times in the conversation, but it’s something that I have not yet mentioned in the two years that I have been writing this blog. John Morgan recently wrote an article on the issue and I have invited him to post a guest blog that goes into some more detail. It touches on a very fundamental issue: one cannot develop a new energy source that requires more energy for production than that which it generates. It’s long been the “gold standard” for approximating the remaining level of fossil fuels available. If, for instance, there is an oil deposit that requires more energy (and money) to extract than that gained by its extraction, no one would bother with the effort (therefore, that deposit is not counted among available resources). With sustainable energy sources the estimates are a bit more complicated but the concept remains the same.

Stay tuned.

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Make it Simple, Please!

Many years ago, I was invited to a small gathering of scientists that did work on solar cells. The invitation came from the Department of Energy (DOE), which coordinates funding to these projects. The conference was focused on creating a common language between scientists and the bureaucrats in charge of funding such projects. We started the meeting with short presentations of our work. The dominant message from the DOE people was: simplify it! They argued that they have to report to congress and, as a rule, a “typical” congressman doesn’t know terms such as “logarithmic scale,” “rate constant,” or “conversion efficiency,” all of which are customary phrases among scientists that do work in the field. We started to argue that these concepts are essential, but we quickly gave up. This event took place before climate change became the existential topic it is today, that requires the global collective action that we are striving to achieve.

Now we are in a different situation. Climate change is a global threat that needs mitigation on a global scale. For this to happen, we need leadership that can follow the issues. In many countries this leadership needs to be elected; in all cases, it is vital to keep such people in office. To satisfy these requirements, all of us need to understand the issues; that means they must be presented in a manner that does not require any academic prerequisites. We need messages that can be put on posters similar to the ones that we saw in abundance during September’s People’s Climate March (September 23 and 30, 2014 blogs). The global institute that was put in charge of delivering said message is the IPCC. I have discussed the IPCC often in this forum. It issues reports periodically, upon which most of the public conversation is then anchored; the last report (AR5), which came out a year ago, consists of three sections:

The first chapter in all three group reports is titled “Summaries for Policy Makers.” This is the same kind of audience that the DOE personnel from my earlier meeting were trying to address.

All of the graphs on this blog are taken from these chapters. I will start with the one that will make my point in the clearest possible way:

IPCC Cutting-EmissionsYes, I know: very “simple” :( . A great poster for a march :( and great rallying cry for action :( .

It does, however, contain a lot of credible information. It contains possible emission pathways under different scenarios. The IPCC uses the mechanism of different scenarios to predict the future. They do not favor one scenario over another; they just describe the consequences that will happen if the world follows a particular scenario. Before the last report, the IPCC was using 40 different scenarios; for the last report, they changed the process in which they construct scenarios. The scenarios are stories. One can find a good, relatively simple description of the scenario process in the blog Skeptical Science, under the title “The Beginner’s Guide to Representative Concentration Pathways.”

I personally both can and do spend a full lecture discussing this graph with my classes. As a policy maker, on the other hand, I would be looking at the graph and trying to decide not only what to do based on the information it provided me, but also how to then justify those actions to my constituents so they will elect me for another term. Try it!

I have included two more graphs that are often used to introduce audiences to the consequences of climate change. Both are taken from the same chapters; respectively, they predict the temperature rise and the sea level rise:

IPCC Global average surface temperature change

IPCC Global mean sea level riseThey are a bit simpler than the first graph, but contain the same elements. These graphs are among the simplest in the reports.

The scenario-based analysis of the future has its place, but that place should be in the technical literature – not as a “Summary for Policy Makers,” and not as a rallying cry for action.

For such a purpose, two scenarios are perfect as a message for the policy makers and a rallying cry for the general public: one “business as usual,” which predicts the consequences for the physical environment if we continue doing what we are doing now, and the other, “environmentally friendly” that will stabilize the condition of the physical environment. These would necessarily include details about what it takes to go from one scenario to the other.

The “business as usual” scenario changes with time. That’s fine; in every report, one should be able to see if we are making progress toward a sustainable scenario or if instead we are retreating from that goal.

A graph like that exists in recent reports; in fact, I have shared it a few times before on this blog (September 24, 2012):

IPCC Ecosystem Risks Fork

My book, Climate Change: the Fork at the End of Now was directly inspired by this graph. You can see the fork in the two scenarios and you can easily identify the conditions that lead to either side of the fork. The writing on the graph describes some of the consequences of being on the left side of the fork. The color is nice for emphasis but is not absolutely necessary. The graph starts early enough to superimpose measurements and predictions. It is simple enough to put on posters and to use it as a battle-cry.

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