Inequality – Responses to Piketty

In last week’s blog, I focused on Piketty’s book and my reading of it. As I mentioned there, the volume of responses to the book was overwhelming. Some of the responses focused on the book, but many of them tackled the issue itself. Not surprisingly, there was a considerable amount of repetition in the responses. As I promised last time, this blog will summarize some of the main issues that they raised. Because this blog is focused on public responses, I have compiled excerpts of responses, mostly as posted in the “New York Times,” my main source of information on current events.

I will start with the obvious: Nicholas Kristoff’s Op-Ed in the “New York Times,” (July 24, 2014) entitled: “An Idiot’s Guide to Inequality.”

He starts with restating the observation that Frank Rich made (see last week’s blog) about the book’s low score under the “The Hawking Index.” Here are his exact words:

We may now have a new “most unread best seller of all time.” Jordan Ellenberg, a professor of mathematics at the University of Wisconsin, Madison, wrote in The Wall Street Journal that Piketty’s book seems to eclipse its rivals in losing readers: All five of the passages that readers on Kindle have highlighted most are in the first 26 pages of a tome that runs 685 pages.

Unlike, Frank Rich’s, which reviewed Hillary Clinton’s book, Kristoff’s Op-Ed zeroes in on Piketty’s book. As a remedy for the book’s low readership, he introduces us to the “Idiot’s Guide to Inequality.” Here are the elements of his “guide”:

First, economic inequality has worsened significantly in the United States and some other countries. The richest 1 percent in the United States now own more wealth than the bottom 90 percent. Oxfam estimates that the richest 85 people in the world own half of all wealth. The situation might be tolerable if a rising tide were lifting all boats.

Second, inequality in America is destabilizing. Some inequality is essential to create incentives, but we seem to have reached the point where inequality actually becomes an impediment to economic growth. Certainly, the nation grew more quickly in periods when we were more equal, including in the golden decades after World War II when growth was strong and inequality actually diminished. Likewise, a major research paper from the International Monetary Fund in April found that more equitable societies tend to enjoy more rapid economic growth.

Third, disparities reflect not just the invisible hand of the market but also manipulation of markets. Joseph Stiglitz, the Nobel Prize-winning economist, wrote a terrific book two years ago, The Price of Inequality, which is a shorter and easier read than Piketty’s book. In it, he notes: “Much of America’s inequality is the result of market distortions, with incentives directed not at creating new wealth but at taking it from others.”

Fourth, inequality doesn’t necessarily even benefit the rich as much as we think. At some point, extra incomes don’t go to sate desires but to attempt to buy status through “positional goods” — like the hottest car on the block.

Fifth, progressives probably talk too much about “inequality” and not enough about “opportunity.” Some voters are turned off by tirades about inequality because they say it connotes envy of the rich; there is more consensus on bringing everyone to the same starting line.

One might think that since Standard & Poor’s is a rating agency, it doesn’t have a political agenda, yet – for the first time – they have identified that inequality is causing slow economic growth. Here is their reasoning, as reported by Neil Irwin in the “New York Times” (August 6, 2014) in his article, “A New Report Argues Inequality is Causing Slower Growth. Here’s Why It Matters”:

I asked Beth Ann Bovino, the chief U.S. economist at S.&P., why she and her colleagues took on this topic. “We spend a lot of time trying to think about what the economic outlook is and what to expect ahead,” she said. “What disturbs me about this recovery — which has been the weakest in 50 years — is how feeble it has been, and we’ve been asking what the reasons behind it are.” She added: “One of the reasons that could explain this pace of very slow growth is higher income inequality. And that also might also explain what happened that led up to the great recession.

”From my research and some of the analysis I saw from others, when you have extreme levels of inequality, it can hurt the economy,” she said.

Because the affluent tend to save more of what they earn rather than spend it, as more and more of the nation’s income goes to people at the top income brackets, there isn’t enough demand for goods and services to maintain strong growth, and attempts to bridge that gap with debt feed a boom-bust cycle of crises, the report argues. High inequality can feed on itself, as the wealthy use their resources to influence the political system toward policies that help maintain that  advantage, like low tax rates on high incomes and low estate taxes, and underinvestment in education and infrastructure.

As I mentioned last week, one of my main reservations about Piketty’s book was his use of the word, “global,” when he mainly looked at France, England and the US, only occasionally mentioning other countries, most of which are already developed. Piketty recognizes this deficiency, but has argued that he lacks sufficient data about developing countries to continue his studies there. Here is what the “New York Times” wrote on this issue (July 20, 2014) in an article titled, “Income Inequality is Not Rising Globally, It’s Falling”:

Income inequality has surged as a political and economic issue, but the numbers don’t show that inequality is rising from a global perspective. Yes, the problem has become more acute within most individual nations, yet income inequality for the world as a whole has been falling for most of the last 20 years. It’s a fact that hasn’t been noted often enough.

Inequality is rising because the return on capital is considerably larger than that on labor; Piketty’s solution is to “simply” tax capital above a certain threshold. He recognizes that the taxing would have to be global because otherwise people with capital will run to the nearest tax haven or area with the lowest tax rates (The new term for this, when applied to this phenomenon in business, is “inversion.”). The “New York Times” (July 21, 2014) addresses this issue as well:

Sean Hannity, the Fox News prime-time host, threatened last month to leave New York for a tax haven down south. Tiger Woods transplanted himself from California to Florida for the same reason. The actor Gerard Depardieu decamped from France and sought citizenship in Russia after complaining that 85 percent of his income was consumed by taxes.

“I can’t wait to pay no state income tax down in Florida or Texas,” Mr. Hannity, who lives in Nassau County, said. “I haven’t decided yet, but I’m leaning Florida because I like the water and I like to fish.”

But a new analysis being released Monday undermines the frequent assertion that wealthy people reflexively flee New York City — where Mayor Bill de Blasio campaigned to raise taxes on those who make more than $500,000 — for low-tax states.

The study, by the city’s Independent Budget Office, found that the share of higher-income households that moved from the city in 2012, 1.8 percent, equaled the share of lower-income households that left.

Next week, I will leave off of Piketty, but not the issue of inequality. I will cover the May 23rd “Science” magazine dedicated to inequality, which – in a sense – suggested (to me) a stamp of approval for incorporating inequality into the sciences.

* As always, I welcome questions and comments about my blog, my book, and my work in general. In an effort to reduce the influx of spam, and in the interest of spending my time addressing actual messages (instead of sorting through junk), I ask that you please send any questions to one of the following addresses, with the title, “Comment about CCF blog.”

micha (no space) tom (at) brooklyn (dot) cuny (dot) edu

or info (at) lcgcommunications (dot) com. Thank you for your continued readership and your feedback.

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Income Inequality – Piketty

Summer is about to end and school will start soon. In a few days I will be going on a short trip to Israel to give two talks – one at the Weizmann Institute about water management and climate change, and the other at my high-school reunion. The one at the Weizmann Institute will focus on attempts to ensure that 75 years from now the world will be safe for our grandchildren and their grandchildren. The talk at my school reunion will focus instead on my own attempts to facilitate communication between my generation and that of our grandchildren, using my family as an example. There will be three days between the talks, and the subject matter will cover a span of about 150 years. It makes me feel like a mini Methuselah (according to the Bible he died age 969), which makes life interesting. I have often focused here on the issue of connecting the distant past with an equally distant future, and I will continue to do so.

In the next few blogs before my trip I would like to focus on an issue that is especially important presently – income inequality. I have addressed the subject before, specifically in the February 4, 2013 blog in connection with sustainable economic growth, and the January 7, 2014 blog as it relates to population growth. However, this year the issue took on a new dimension. On the political side it started with the election Bill de Blasio as New York City’s new mayor, and his campaign cry to try to address the city’s growing inequality. The publication of Thomas Piketty’s book, Capital in the Twenty-First Century, (translated to English by Arthur Goldhammer), only served to amplify the importance of the issue.

I am a physicist (trained as a physical chemist), and I teach two courses in which income inequality plays an important role: climate change and “Physics and Society.” In both courses whenever I mention inequality, my students’ typical response is: “Why should we care? We are here to end up on top.” Both courses are highly interdisciplinary and deal with subjects that I never studied in school; instead, I have tried to self-educate myself throughout the years. Economics is probably the most important of these disciplines. In the more than two years that I have been writing this blog, it has surfaced repeatedly. As a result, I decided to spend part of my recent vacation-work trip to Europe (June 10, 24, 2014 blogs) trying to read Piketty’s book in full. I did it (all 700 pages worth :( )! When I came back I read Joseph Stiglitz’s new book, The Price of Inequality (W.W. Norton & Company, 2013). I also found that “Science” magazine, one of the most prestigious scientific journals, dedicated a significant fraction of its May 23rd issue to articles about inequality. In a sense, this summer was the summer of inequality for me and I want to share some of it with you.

I will start with Piketty’s book, continue through some of the many public reviews and comments that have shown up on an almost daily basis since its publication (April 2014), follow up with highlights from the Science issue and finish with attempts to correlate all of this with sustainability and climate change. Throughout this series of four blogs I will intersperse my own takes on these issues.  To put it into perspective, Frank Rich in an article in New York Magazine (August 12, 2014; page 46 ) titled “Good Hillary, Bad Hillary” described a new statistical tool called, “The Hawking Index,” which examines readership. It was created by Jordan Ellenberg, a Wisconsin Mathematician. The index is named after Stephen Hawking’s book, A Brief History of Time, about the beginning of the Universe in the Big Bang. The index is supposed to compute how thoroughly best sellers are being read (For example, Donna Tart’s Goldfinch scored a whopping 98.5%). At the bottom of the index, breaking Hawking’s previous low of 6.6%, came Thomas Piketty’s Capital in the Twenty-First Century with a score of 2.4%.

Regarding Hawking’s book, I still remember an episode in London when I tried to buy the book as a present for my stepfather. I went to a reputable book store and asked for the book; they sent me to the History section. I immediately realized, (this was many years before the creation of the “Hawking Index”), that popularity and readership are not necessarily the same.

Piketty bases his analysis on detailed examination of data and the argument that capitalism is based on two fundamental laws. This sounds similar to Physics, where significant parts of the macroscopic physical environment are based on the 1st and 2nd laws of thermodynamics (you can use the Search button on the side to see previous mentions of thermodynamics in this blog). The laws are very simple and are given in a form of two formulas:

  1. α = r×β
  2. β = s/g

α is the share of income that comes from capital; β is the ratio of capital to the national income; r is the rate of return from capital; s is the savings rate and g is the growth rate.

To use two numerical examples from the book: in equation 1 if β = 600% and r = 5% it follows that α = 30%. Likewise, in equation 2, if we say that the savings rate (s) is 12% and the growth rate (g) is 2%, it implies that β = 600%. Significantly, the second law implies that a country that saves a lot but grows slowly accumulates large capital (relative to its income). Piketty places the two laws at the heart of the central contradiction of capital. Put simply, if the return on capital is greater than the general growth of the economy, then this will inevitably lead, over time, to those with capital increasing their wealth in relative terms, until they eventually own all capital and thus put an end to capitalism itself. With the return increasing over time, when given access to various assets, capital will get a larger share of income. In fact, when wealth is inherited and can be diversified, the returns are higher than in case of an individual who has limited wealth and prefers safer avenues which earn lower returns.

A typical data set on which his analysis is based, is given below:

The figure is in the book but in a bit less attractive form at least in my version of the book (the electronic version). I took this version from Google images instead.

The figure is in the book but in a bit less attractive form at least in my version of the book (the electronic version). I took this version from Google images instead.

The figure depicts the share of total national income held by the top percentile of the population in four Anglo-Saxon countries over the 20th Century. Similar trends can be seen in the French data. It is obvious from the graph that over most of this time, the share of income does not obey the “basic laws of capitalism,” because the share of income held by the top percentile is actually decreasing, not increasing as the laws would predict. Piketty claims that the laws are not obeyed over this period because the period was dominated by the two World Wars in which massive capital was destroyed. This is certainly true in France and Germany, which are not shown here, but the claim is a bit questionable, to a variable degree, for the four countries shown in the graph. Regardless, for what it is worth, based on the two laws, the claim itself that capital grows considerably faster than income makes sense (at least to me).

Another important issue is that the claim of global behavior, which he uses as a predictor for the future, is based mainly on three countries: France, England and the USA. The analysis and the predictions are based on analysis of historic data and Piketty was not able to find similarly extensive data sets for other countries. This is problematic for numerous reasons.

Be that it as it may, I return to my students’ recurring question – so what? If some guys are getting richer and the standard of living (in real $) for most of the rest of the 99% remains approximately the same (and we belong to the 99%), why should we care? Why not just strive to join the 1% and let the magic of the free market work its way?

I will try to address some of these questions and how they relate to the book in the next three blogs. Meanwhile, I’d like to finish here with an observation unique to the US. A recent US Supreme Court decision, which passed by a margin of 5:4, started with the following paragraph:

In the Court’s plurality opinion, Chief Justice John Roberts wrote, “The right to participate in democracy through political contributions is protected by the First Amendment, but that right is not absolute. Our cases have held that Congress may regulate campaign contributions to protect against corruption or the appearance of corruption. See, e.g., Buckley v. Valeo, 424 U.S. 1, 26-27 (1976) (per curiam).”

The resolution states that spending money on an election is protected by the First Amendment, as is free speech. The only exception is that Congress may regulate campaign contributions to protect against corruption or the appearance of corruption. This means that the ever-increasing share of capital owned by the top 1% of the population – a resource that provides this group with the unopposed ability to sway elections – cannot be limited by Congress. Using such monetary expenditure to gain more and more influence on the political process, resulting (for example) in the lowering of taxes, modification of antitrust legislation or reduction of welfare payments, is not considered “quid pro quo,” meaning that it is not considered corruption or appearance of corruption, and thus cannot be limited.

* As always, I welcome questions and comments about my blog, my book, and my work in general. In an effort to reduce the influx of spam, and in the interest of spending my time addressing actual messages (instead of sorting through junk), I ask that you please send any questions to one of the following addresses, with the title, “Comment about CCF blog.”

micha (no space) tom (at) brooklyn (dot) cuny (dot) edu

or info (at) lcgcommunications (dot) com. Thank you for your continued readership and your feedback.

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Energy Storage Selection

This will be the last blog to deal directly with storage technologies. I listed the various technologies in the July 29th post, then followed that up last week, mainly focusing on estimates of future capacity and the investments that will be needed to decarbonize the energy supply. The necessarily increased reliance on sustainable energy sources requires investing in technologies that separate energy generation from energy use, users from producers. If we go into the specifics of the storage technologies that I mentioned in the July 29th blog, the following picture emerges:

Capital Cost Per Unit Power

Power quality determines the compatibility between various types of electrical power and consumer devices. An important consideration in such a match is that the supply power must be uninterruptible (UPS). I have discussed the difference between energy and power before; here, the horizontal axis refers to the initial capital cost for the storage device per unit of power (in kw) that it can deliver, while the vertical axis refers to the cost per unit of energy stored over the lifetime of the device.

Cost is not the only consideration that determines which technology to use. The uninterruptible power requirement necessitates that the system be able to quickly respond to changes in supply and demand. Long-term changes in terms of weeks or months are relatively easy to predict and offer sufficient time to adjust changes in supply with changes in demands. Short-term changes – such as heat waves, which require immediate adjustment in power, as needed for air conditioning – are more difficult to predict and adjust to. Many of the recent grid blackouts have emerged as a result of such short-term surges in demand. The various storage devices’ compatibilities are measured by their discharge times. These characteristics are shown in the figure below:

Electricity Storage Technologies Graph

Capacity, again, is a measure of the power of the devices.

The scales in both graphs are logarithmic scales (August 6, 2012) in which equal distance on the axes indicates factor of ten differences in value. (In other words, the differences are large)

The need for storage capacity recently reached the big news with Tesla Motors’ announcement of a plan to construct a Gigafactory for Li-ion batteries for its electric car fleet; a project with an estimated cost of $4 billion. Panasonic has now decided to join this effort, investing both money and equipment. The factory aims to start producing batteries in 2017.

Why did Tesla choose the Li-ion over the Lead-Acid battery? The first figure clearly shows that the Li-ion batteries are more expensive both per unit of power and per unit of energy as compared to lead-acid batteries, so other considerations must be at play. The Gigafactory is targeted toward supplying batteries for electric cars. This means weight must be another important factor. The table below shows the energy stored in the two batteries per unit of weight of the battery. This parameter is known as the energy density. The data in the table are based on those in the Wikipedia entry. The energy density of the two batteries is shown in comparison with that of gasoline. The energy density of Li-ion is four times higher than that of lead-acid batteries but is still about 75 times lower than that of gasoline. These numbers indicate the relative advantage of the Li-ion over the lead-acid battery but at the same time convey the enormous challenge facing manufacturers of electric cars as compared to those that make gasoline-driven vehicles.

Storage device

Specific Energy (MJ/kg)

Specific Energy (kwh/Lb)

Gasoline

46

5.86

Li-ion battery

0.62

0.08

Lead-Acid battery

0.17

0.02

A word about the units in the table: The two right columns present the same data in different sets of units: the right column corresponds to the units that are predominantly used in the US, while the central column is given in units widely accepted in the rest of the world. The conversion is as follows: 1MJ = 0.28kwh; 1kg = 2.2Lb. It is a great exercise to try this conversion – especially for American readers – because it helps open our windows of comprehension to more global information.

* I always welcome questions and comments about my blog, my book, and my work in general. Unfortunately, I have been deluged with spam – both in the comments section here, and in my email. In the interest of spending my time addressing actual messages (instead of sorting through junk), I ask that you please send any questions to one of the following addresses, with the title, “Comment about CCF blog.”

micha (no space) tom (at) brooklyn (dot) cuny (dot) edu

or info (at) lcgcommunications (dot) com. Thank you for your continued readership and your feedback.

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CCF Special Mini-post: Response to Twitter, Article by David MacKay

If you’re not following me already on social media, I hope that changes now (Facebook, twitter). I tweet about my new posts, and share some great articles that I come across. I also pay attention to messages from my followers. I recently got a tweet directed my way from Dadiva Netter – @sidnets, asking me to comment on a paper by David MacKay (Former Chief Scientific Advisor, DECC, and Regius Professor of Engineering at Cambridge, who is also on twitter) that was submitted to the Royal Society.

Since I’m still not completely used to condensing complex thoughts into 140 characters, I’m including my full response here, and linking to it through twitter:

Thank you Dadiva for directing my attention to this important article. It is a significant quantitative contribution to the requirements necessary for a global energy transition to decarbonized energy sources based on solar energy conversion in all its forms. It makes the key point that although globally there is plenty of energy coming in, locally there are imbalances that require separating energy production from consumption. The emphasis in the paper is on sovereign states (with Britain as a focal point), but in-state disparities – especially between dense populations of urban consumers and equally dense rural production areas – require extensive investments in storage and smart grids capable of covering a large area. In my downloaded copy, I started highlighting important paragraphs for later reference, and ended up yellowing the entire article. I will also use the article in my class on climate change.

I’d be delighted to address the article in more detail – either on my own or in response to you joining me as a guest blogger (how about it?).

I’d also love to invite David MacKay on to Climate Change Fork to talk about his article. Please let me know what you think at michatom (at) brooklyn (dot) cuny (dot) edu.

Thanks everyone, and have a great weekend!

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The Economics of Energy Storage

Two of the last three blogs (July 15 and July 29, 2014) discussed the role that energy storage plays in the transition to more sustainable energy sources. In my last blog, I tried to discuss the available technologies. This week, I will put the emphasis on the economics, while in the next one (assuming that nothing “urgent” interferes), I will focus on the considerations that take place in the selection process of which technologies to apply.

In order to discuss the economics of needed storage, let’s focus on a  recent IEA (International Energy Agency) report; it came up with a roadmap for the global storage technologies required in order to accommodate an energy transition aimed at limiting the global temperature rise to below 2oC. The main conclusions of this report are summarized below:

  • Energy storage technologies are valuable in most energy systems, with or without high levels of variable renewable generation. Today, some smaller-scale systems are cost competitive or nearly competitive in remote community and off-grid applications. Large-scale thermal storage technologies are competitive for meeting heating and cooling demand in many regions.
  • Individual storage technologies often have the ability to supply multiple energy and power services. The optimal role for energy storage varies depending on the current energy system landscape and future developments particular to each region.
  • To support electricity sector decarbonisation in the Energy Technology Perspectives (ETP) 2014 2DS, an estimated 310 GW of additional grid-connected electricity storage capacity would be needed in the United States, Europe, China and India. Significant thermal energy storage and off-grid electricity storage potential also exists. Additional data are required to provide a more comprehensive assessment and should be prioritized at the national level.
  • Market design is key to accelerating deployment. Current policy environments and market conditions often cloud the cost of energy services, creating significant price distortions and resulting in markets that are ill-equipped to compensate energy storage technologies for the suite of services that they can provide.
  • Public investment in energy storage research and development has led to significant cost reductions. However, additional efforts (e.g. targeted research and development investments and demonstration projects) are needed to further decrease energy storage costs and accelerate development.
  • Thermal energy storage systems appear well-positioned to reduce the amount of heat that is currently wasted in the energy system. This waste heat is an underutilized resource, in part because the quantity and quality of both heat resources and demand is not fully known.

Focusing on the United States, India, China and the European Union, the IEA calculates the necessary daily capacity for electricity storage and the corresponding investments that are vital to satisfying all of these countries’ energy storage needs in 2050. The data are presented for three different scenarios for capacity building:

  1. 2DS scenario – this is the baseline scenario where renewable energy technologies are increasing their share of worldwide electricity generation from about 20% in 2011 to about 65% in 2050, with variable renewals supplying 29% of the total electricity produced globally. This scenario corresponds to approximate requirement to limit the global temperature increase to 2oC.
  2. A “breakthrough” scenario that assumes aggressive reduction in the cost of storage
  3. “EV” scenario where demand response from “smart” charging of electrical vehicle fleet in the 2DS scenario provides additional flexibility to the system.

The two figures below, marked “figure 7” and “figure 9” (from the original report), show some of the most important aspects of the results.

Figure 7:  Electricity storage capacity for daily electricity storage  by region in 2011 and 2050 for ETP 2014 scenarios

IEA Electricity Storage Capacity for Daily Electricity Storage by Region MichaIEA Investment Needs for Energy Storage in Different ScenariosThese figures need some brain tutoring enforcements. The second figure is self-explanatory – we all understand how much $1 billion is, and all 4 regions need to spend around $150 billion (each) – based on the 2DS scenario – to satisfy their storage needs, and that constitutes big money. It is worth noting here that the same amount is about 50 times bigger for India than it is for the US and Europe as compared with present GDP.

The units in the first graph are a bit more interesting, so let us try to calculate their significance from first principles: I will focus again on India and the United States. The figure indicates that in 2011, the daily electricity storage in the United States was about 20GW (1 GW = 1 gigawatt = 1 billion watts), while in India that storage was very close to zero on this scale (I will take it to be 1 GW for this calculation). Again, India has much more work to do to get to the 2050 target based on this scenario. In both cases, based on the 2DS scenario, the need will increase to about 80 GW. How significant are these numbers and how can we relate to them based on first-principle calculations?

My data source for most of these kinds of calculations is the World Bank. According to the World Bank, the population of India in 2011 was about 1.22 billion (1.22×109 using Scientific Notation) while that of the United States was 322 million (3.22×108). The electric power consumption that year in the United States was 13,246 kwh/capita (1kwh = 1 kilowatt hour = 1000 watt hours) while that in India was 684 kwh/capita.

This is highly confusing and my editors will start climbing trees claiming that this is rocket science for the “average” reader and I should “simplify.” You are not an “average” reader, though, so let’s try to go through the complexities.

The most confusing thing here should not be the numbers but the units. The figure lists electricity storage in units of billion watts. We know that a watt is not a unit of energy but a unit of power (think of the rating of a light bulb – as 60 watt or a 100 watt). To convert power to energy we have to multiply the power rating by the time that we use it. So when we pay the electric bill we don’t pay for the power but for the energy that we use. When we leave a 100 watt light bulb on for 10 hours we use 100w x 10hrs = 1000 watt-hours = 1kwh of energy. So if we want to calculate the amount of energy in 1 GW of daily energy storage it will give us 1 billion watts x 24hrs = 24 gigawatt-hours of energy/day, the needed energy storage for the United States in 2011 is 20GW = 24×20 gigawatt-hours/day = 480 gigawatt-hours/day.

According to the World Bank, the average energy consumption in the United States in 2011 was 13,246 kwh/capita. We need to multiply this number by the US population in 2011 to get the total electricity consumption for that year. This results in 4.3×1013 kwh/year (try it!). We then divide this number by the number of days per year to get 11.8 billion kwh/day = 11,800 gigawatt-hours/day.

The needed energy storage for the United States in 2011 is 480/11,800 = 4% the average electrical energy consumption for that year.

A similar calculation of India’s data produces 684 kwh/capita x 1.22×109 people = electric energy consumed in 2011 = 834 billion kwh/year or 2.4 billion kwh/day = 2400 gigawatt-hours/day. The present storage requirement based on 1GW is 24 gigawatt-hour/day. So the Indian storage requirement amounts to only 1% of their daily use of electricity.

Based on the 2DS scenario the projected storage requirements in the US in 2050 will increase 2.5 fold from today’s figures, while those of India will be 50 times larger. These are enormous numbers that present both massive challenges and equally large business opportunities. People all over the world are beginning to realize that.

 

* I always welcome questions and comments about my blog, my book, and my work in general. Unfortunately, I have been deluged with spam – both in the comments section here, and in my email. In the interest of spending my time addressing actual messages (instead of sorting through junk), I ask that you please send any questions to one of the following addresses, with the title, “Comment about CCF blog.”

micha (no space) tom (at) brooklyn (dot) cuny (dot) edu

or info (at) lcgcommunications (dot) com. Thank you for your continued readership and your feedback.

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Storage – the Technologies

A quick note: this week’s post is a bit of a science challenge and requires some further investigation by the reader. Please click through to the links and email me if you have any questions.

The Energy Storage Association (ESA) lists the following electric storage technologies:

  • Solid State Batteries – a range of electrochemical storage solutions, including advanced chemistry batteries and capacitors (Electrochemical Capacitors, Lithium Ion (Li-Ion) Batteries, Nickel-Cadmium (Ni-Cd) and Sodium Sulfur (NAS) Batteries)
  • Flow Batteries – batteries where the energy is stored directly in the electrolyte solution for longer cycle life, and quick response times (redox Flow Batteries, Iron-Chromium (ICB Flow Batteries, Vanadium Redox (VRB) Flow Batteries and Zinc-Bromine (ZNBR) Flow Batteries)
  • Flywheels – mechanical devices that harness rotational energy to deliver instantaneous electricity
  • Compressed Air Energy Storage - utilizing compressed air to create a potent energy Reserve (Compress Air Energy Storage (AA-CAES), Advanced Adiabatic Compressed    Air Energy Storage (AA-CAES) and Isothermal CAES)
  • Thermal – capturing heat and cold to create energy on demand (Pumped Heat Electrical Storage (PHES), Hydrogen Energy Storage and Liquid Air Energy Storage (LAES) )
  • Pumped Hydro-Power – creating large-scale reservoirs of energy with water (Pumped Hydroelectric Storage, Sub-Surface Pumped Hydroelectric Storage, Surface Reservoir Pumped Hydroelectric Storage and Variable Speed Pumped Hydroelectric Storage)

The technical ESA’s website also presents details of each storage method. There are, however – to use a common college term – some “prerequisites” necessary before we can follow up on these details. That kind of targeted educational background is something that most of us do not have. Since describing it in terms that don’t require such prerequisites requires a lot of effort and takes great deal of time for both the reader and writer, I will skip most of the explanations here. Anyone who wants to learn more about these storage modes is welcome to try his/her hand on the appropriate Wikipedia sites (If you hadn’t noticed yet, I tend to like Wikipedia as a source for quick, well-written information). Instead, for the moment, I will focus on two important categories: Solid State Batteries and Pumped Hydro-Power.

Solid State Batteries:

On a hot summer weekend, my wife and I were invited to visit friends in suburban NYC. The friends live in a house with a swimming pool and they invited us to take advantage of it. The gathering was pleasant and intimate, with us the only guests. I was sort of swimming around alone in the pool with everybody else chatting outside. Suddenly, the hostess called to me, saying that they needed some technical advice. The discussion topic was the cost of upkeep of the pool. They all agreed that it is ridiculously expensive and they were trying to find a better solution. My hostess got a proposal to save on chlorination by using a common salt and she asked me how it works. It had been a long time since I had to deal with swimming pool maintenance so I had to explain, using basic chemistry, that the only way that I can think of that it would work is through the use of electricity in an electrolytic process. Therefore, in order to figure out if the new system is a money saver, we will have to figure out if what she saves on chlorination will not be balanced out by the combination of an extra-large electric bill and the prices of the electrolyzer and regulator (more than $2,000). She shook her head and said the only thing that she knows about such matters (she is a college educated teacher) are the + and in her car battery. Here is what Wikipedia says about the chlorination gadget:

Salt water chlorination is a process that uses dissolved salt (2,500–6,000 ppm) as a store for the chlorination system. The chlorine generator (also known as salt cell, salt generator, salt chlorinator) uses electrolysis in the presence of dissolved salt (NaCl) to produce hypochlorous acid (HCIO) and sodium hypochlorite (NaClO), which are the sanitizing agents already commonly used in swimming pools. As such, a saltwater pool is not actually chlorine-free; it simply utilizes a chlorine generator instead of direct addition of chlorine

Since I’m using her as a representative of general public knowledge, I guess we had better start with what she knows. Probably, the simplest battery that all of us know about is the Lead-Acid battery that are in use in most cars. I also found that this battery probably offers the simplest explanation how batteries in general work. The Lead-Acid is not even listed in the ESA list of batteries. If we look for a battery entry in Google and read the Wikipedia entry we find 20 different batteries (not the mere 4 shown on the ESA list). The working principle is similar to that of the Lead-Acid battery but the chemistry is different. Here is the simplest example that I could find of how the Lead-Acid battery works:

Lead-Acid BatteryFor reference, the compounds above are as follows: H2SO4 - Sulfuric Acid, PbO2 – Lead Oxide, PbSO4 – Lead Sulfate, H2O –Water, Pb – Lead.

In the charging process Lead (Pb) is deposited from the Lead Sulfate (PbSO4) onto the negative electrode and at the same time Lead Oxide (PbO2) is deposited on the positive electrode. In the discharge process the reverse reactions take place. We use excess electricity to charge the battery and use this electricity when we have access demand. For a more detailed walk-through of the chemical process, you can go here.

Hydro-Power Storage:

Here the science is considerably simpler. A schematic is shown in the picture below: hydroelectric power station 2For storage we use electrical power to pump water to a reservoir uphill and when we need the extra power we use the stored water to run the power station below like a regular hydroelectric generation.

How do we convert the water flow into electricity? The process is similar to that of generating electricity from power plants run on fossil fuels such as coal and natural gas. In both cases we turn a propeller like a turbine that moves a magnet relative to conducting wires. This phenomenon produces electric power in a way that was originally demonstrated by the English scientist Michael Faraday (1791- 1867). Water is the most widely used storage device for power generating facilities but other materials can be used for the same purpose. Perhaps one of the most interesting variants is based on a loaded train that is driven uphill powered by access electricity and downhill to generate electricity when needed. The stored energy can be adjusted by changing the weight loaded. It can operate in places where hydroelectric storage is not practical.

The discussion with my friend about the cost-effectiveness of salt water chlorination is ongoing, but I will let you know when we reach a conclusion.

In future blogs I will focus on some of the economic considerations when choosing what storage devices to use and how to incorporate them into the grid structure.

* I always welcome questions and comments about my blog, my book, and my work in general. Unfortunately, I have been deluged with spam – both in the comments section here, and in my email. In the interest of spending my time addressing actual messages (instead of sorting through junk), I ask that you please send any questions to one of the following addresses, with the title, “Comment about CCF blog.”

micha (no space) tom (at) brooklyn (dot) cuny (dot) edu

or info (at) lcgcommunications (dot) com. Thank you for your continued readership and your feedback.

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Sustainable China?

In the last blog I started to discuss the role that energy storage plays in the transition to more sustainable energy sources. While I had originally planned to focus this blog on the various energy storage technologies, I will instead postpone that subject for a later blog. Instead, as often happens (at least to me) current events diverted my attention to a different topic.

This time, the trigger for the change was a short piece in the online magazine Renewable Energy World.com. I am a subscriber and a regular reader of this magazine. Elisa Wood, a writer from the organization was my guest blogger here on May 6, 2014 and I contributed to her May 31, 2013 blog regarding adaptation to climate change. A few days ago, the following piece by Alexandra Ho from Bloomberg showed up in their publication:

China Requires Electric Vehicles to Make Up 30 Percent of State Purchases

Alexandra Ho, Bloomberg

July 14, 2014

SHANGHAI — China is mandating that electric cars make up at least 30 percent of government vehicle purchases by 2016, the latest measure to fight pollution and cut energy use after exempting the autos from a purchase tax.

Central government ministries and agencies will take the lead on purchases of new-energy vehicles, a term that China uses to refer to electric vehicles, plug-in hybrids and fuel-cell autos, according to a statement on the central government’s website yesterday. The ratio will be raised beyond 2016, when local provinces are required to meet the target.

China is stepping up support for electric vehicles as demand lags behind its target because of consumer concerns over price, reliability and convenience. The government has identified EVs as a strategic industry to help it gain global leadership, reduce energy dependence and cut smog that often reaches hazardous levels in Beijing and other cities.

“This is a laudable aspiration,” said Yang Song, a Hong Kong-based analyst at Barclays Plc, who estimates that government purchases made up less than 10 percent of total new vehicle sales in China. “Government purchases are not growing as fast as private consumption. So just to rely on the government purchase would be a challenge.”

Last week, China announced the waiver of a 10 percent purchase tax for new-energy vehicles, excluding them from the levy beginning Sept. 1 to the end of 2017, the central government said in a statement posted on its website on July 9.

BYD Co., the electric automaker partially owned by Warren Buffett’s Berkshire Hathaway Inc., climbed 3.6 percent to HK$48.90 as of 11:47 a.m. in Hong Kong trading. The benchmark Hang Seng Index gained 0.4 percent.

Electric Vehicles

The measures announced yesterday by the National Government Offices Administration also direct agencies to give preference to all-electric vehicles in purchases, while cold-weather jurisdictions may consider plug-in hybrids. Electric sedans should cost no more than 180,000 yuan ($29,000) after subsidies.

Government organizations and public institutions will be required to add parking spaces reserved for new-energy vehicles and ensure the ratio of charging facilities to the vehicles is equal, according to the plan.

Local officials will be held responsible if the targets aren’t met, according to the statement.

Copyright 2014 Bloomberg

This caught my eye because for years there has been a tendency to view electric cars as an important and visible component of energy transformation to more sustainable energy sources. They are not.

Electricity is a secondary energy source. Its sustainability depends on the primary energy sources. If we produce the electricity from solar, wind, hydroelectric or biofuels – it is sustainable. If we produce it by burning coal it is not.

Here are the primary energy sources from which China is producing its electricity.

total energy consumptionAccording to recent report from EDGAR (Emission Database for Global Atmospheric Research) China is now the largest global emitter of carbon dioxide, at 9.9 billion tons/ year, as compared to the United States, which comes in second at 5.2 billion tons per year. On a per-person basis, the United States is still on top, with emissions of 16.4 tons of carbon dioxide per person, compared to China’s 7.1 tons per person. Both far exceed the global average of 4.9 tons per person.

While there is nothing inherently wrong with a transition toward electric cars, they cannot be heralded as a solution to extremely high emissions. As we can see from the graph above, 69% of China’s energy production comes from coal; from that, we can infer that 69% of the power for an electric car comes, likewise, from coal. The promised move to electric vehicles will not change this situation until China actually changes the energy sources from which it gets its electricity.

* On a separate note, I always welcome questions and comments about my blog, my book, and my work in general. Unfortunately, I have been deluged with spam – both in the comments section here, and in my email. In the interest of spending my time addressing actual messages (instead of sorting through junk), I ask that you please send any questions to one of the following addresses, with the title, “Comment about CCF blog.”

micha (no space) tom (at) brooklyn (dot) cuny (dot) edu

or info (at) lcgcommunications (dot) com. Thank you for your continued readership and your feedback.

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The Missing Link – Energy Storage

In my last blog (July 8, 2014), I tried to summarize my goals for this blog, and take account of my progress to date. I ended with a short paragraph that described my efforts to educate my readers on the necessity of working toward a total global transformation of the way that we live. Under our current “business as usual” scenario (continuing the same patterns have used since the Industrial Revolution), we are – to use a popular but inexact expression – reaching the limit for the planet’s “Carrying Capacity” to accommodate our rate of global population growth and constant increase in the standard of living. I came out with the following short paragraph to describe what is needed:

 The global transformation requires total energy transition to sustainable sources, recycling of finite national resources, reintroduction of fresh water use into the water cycle, curbing untapped exponential growth, establishing effective global governance and, probably most importantly, caring about each other

The first requirement was a total energy transition away from the present dependency on use of fossil fuel. Such fuels change the chemical composition of the atmosphere in a way that significantly impacts our energy balance with the sun, and alters the climate, leading us toward an uncharted and possibly uninhabitable future. I framed this idea previously (April 15, 2014) as a search for a “contemporary Joseph”:

Joseph’s achievement was predicting (based on interpreting God’s enlightenment in the form of Pharaoh’s dreams) the upcoming variability of food supply and rearranging the system accordingly: storing food in the good years to be distributed in the bad years.

If such an enlightening force were to show up today, what would be his/her job description? It would have to include preparing an infrastructure to adapt the world for a changing climate. The climate is changing at a human pace that has, and likely will continue to result in rising temperatures, sea level rise, and a rising variability of droughts and floods. This has/will also contribute to water stress, and therefore agricultural stress – mainly in the poorest parts of the world. Therefore, the job would also require alleviation of this water stress through energy-intensive desalination. In order to mitigate human-driven climate change, we need to go through energy transition; replacing predictable energy sources with highly variable ones.

Sustainable energy and water management are recurring issues throughout the blog. I went back through my more than two years of writing on this blog to find any gaps in my coverage, and I have decided that the most important element that I have missed was the need for storage. I will attempt to remedy that oversight in the next few blogs. After that, I hope to have finished Thomas Piketty’s book (see July 8, 2014 post), and be able to start trying to connect global economic inequities with attempts to mitigate climate change – a totally misunderstood issue, judging from my students’ responses.

Storage is an important element of effective management of resources, especially for both water and energy; however there is one central difference: water management already has one huge storage reservoir where we should focus – our oceans.

The total liquid water on Earth is 1.4 billion km3 (300 million miles3). Our oceans constitute more than 97% of that. The oceans act as large storage reservoirs which naturally supply the fresh water that we use through the water cycle. This supply can be also supplemented by way of energy intensive artificial desalination processes. The equivalent storage of energy are the fossil fuel reserves, on which we rely for energy withdrawals for 85% of our energy needs. As I have mentioned repeatedly before, the essence of the energy transition is to replace this source of energy with sources that don’t leave imprints on the chemistry of the atmosphere. These alternative energy sources include solar in its various forms (photovoltaic, thermal, wind and hydroelectric), nuclear and geothermal.

Even in the business as usual scenario of using our energy (85% from the “naturally stored” fossil fuels) our use of energy is highly variable. A typical variation in electricity use is shown in the two EIA (Energy Information Administration) figures below:

Daily Load Shape

Deployment of energy storage assetsThe delivered power has to be adjusted to the consumers’ demands. The only way to do such a thing is to store excess energy during low demand hours and use it at times of high demand. In the next blog I will discuss the technology of the available storage methods, following which, I will discuss the economics.

It’s important to remember that supplementing and substituting current fuel usage with sustainable energy sources in their various forms, necessitates a greater need for storage. In comparison to fossil fuels, sustainable energy requires more variability – a combination of a wider spatial array and more diverse base of energy sources and consumer distribution in order to deal with irregular consumer use. Patterns in consumer demand are more or less predictable. Patterns in availability of wind and solar are much less so, and grids have to be adjusted accordingly. There is a common view that successful energy transition to more sustainable energy sources will depend on the development of better and more cost effective storage devices. In future blogs I will explore the progress that is taking place towards achieving this objective.

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Keeping Score = Quarterly Reports

Ed Betz/Associated Press Fireworks exploded near the Brooklyn Bridge, over the East River, as part of a Fourth of July celebration in 2005

On the evening of July 4th, I was sitting with my wife on our terrace – watching the beautiful firework display over New York City and New Jersey. As it happened, the New York Times that day came with a full page rendition of the Declaration of Independence. As a good citizen, I reread it. The preamble starts as follows:

When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature’s God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

Watching fireworks in a comfortable setting gives you time to think. My interpretation of what Thomas Jefferson was trying to say (without delving into the rich literature that discusses the issue) is that if a group of people is taking a drastic action, they had better explain themselves – out of a, “decent respect to the opinions of mankind.” My thinking also led me to another upcoming event – July 14: Bastille Day – a French national holiday that commemorates the beginning of the French Revolution, which started with the storming of the Bastille on July 14, 1789.

As I have mentioned in previous blogs, I just came home from a combined vacation-conference trip, on which I spent about two weeks in France – half the time in the South of France and half the time in Paris. Almost everywhere that we went, preparations for the coming celebration of Bastille Day were evident. Following a long-established vacation routine, I took a book to read on my travels. This time, the book was Thomas Piketty’s, “Capital in the Twenty-First Century,” on global wealth distribution. Not being an economist, I decided that the book was a requirement in order to help me understand the dynamics of the political process required for mitigation and adaptation to climate change. I haven’t yet finished its almost 600 pages, but I am close. Once I do so, I will try to share my views as to how his findings connect to my environmental concerns and the long term stability of the planet.

The historic connection between July 4, 1776 and July 14, 1789 has been discussed extensively. To my knowledge, however, the part that has yet to be covered is the connection between the two revolutionary events of the end of the 18th Century, which created the two countries as we now know them, and the similarly revolutionary global transformation that is needed to mitigate future catastrophe and global environmental deterioration. The global transformation requires total energy transition to sustainable sources, recycling of finite national resources, the reintroduction of fresh water use into the water cycle, curbing untapped exponential growth, establishing effective global governance and, probably most importantly, caring about each other. Collectively, we as a world don’t have a Bastille to storm; such a transformation is not an immediate revolution and can take a generation or two to achieve. I have outlined most of the needed changes in previous blogs, and they can be found in many other forums. What I am trying to do here is to combine the reasoning for the needed changes with anecdotal accounting of the progress that is being made and the setbacks that we encounter.

The idle time watching the fireworks convinced me that, following the Jeffersonian dictum, I need to follow the business world’s modus operandi and try to keep score of the progress in regular quarterly intervals.

The intervals that I propose are separated by the following events:

  • The commemorations of the American and French Revolutions (first two weeks of July)
  • The Jewish religion’s holy day, Yom Kippur – a day in which Jews are advised to take accounts of their doings and undoings (beginning of October)
  • New Year’s Day (January 1st)
  • Earth Day (April 22nd)

However, following the state of global transformation is not nearly as easy as following the finances of individual companies. Reliable data sets such as those from the World Bank or the UN get their information from member states with very different statistical histories. The process usually has a lag time of one or two years and not all the information that we are looking for (effective global governance, for example) is quantifiable.

Presently there are attempts to rank individual countries on a similar set of criteria. I used to devote a full semester of class time to teaching such ranking skills and the methodologies of acquiring the needed information. The Columbia-Yale ranking is done on a yearly basis. My quest to try to summarize global progress on a quarterly basis might be a fool’s errand, but I hope to share my first attempt with you in three months’ time.

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I’m Back – Some Notes on Iceland and Sustainable Energy

Well, it’s now July 1st, and I am back home from my combined vacation, family meeting and conference in Iceland. My jet-lag is still in full swing but not enough to freeze me out of the blog schedule. The conference in Iceland was productive; I copied the agenda in a previous blog (June 10, 2014). As is my usual habit after these conferences (July 16, 2012 – Seattle and July 2, 2013 – Mauritius), I was hoping to describe some of the highlights of the conference, as they directly relate to the host country. Unfortunately, I cannot do so in this case because the plenary lectures did not include discussions of the environmental or energy policies of Iceland. I got most of my information from a tour guide that helped us visit this beautiful country. Since Iceland is unique in being almost completely energized by sustainable energy, I have dedicated this to Iceland, despite its omission from the conference.

One of the most important topics in the conference (including my own contribution) was the availability and management of fresh water throughout the world. Iceland runs on water – both cold and hot. About 75% of its electricity is hydroelectricity, which is generated by water falls, while the other 25% of the power is generated by geothermal energy. 87% of the country’s heating and hot water are fueled by geothermal hot water and steam. Right now only about 19% of its primary energy comes from fossil fuels, and these are used primarily for transportation.

Iceland is a sparsely populated (325,000 people) volcanic island that borders the Arctic Circle. On arriving to Iceland on Thursday, June 26, we took a tour that started at 4pm and ended at midnight – it still wasn’t dark! While it probably wasn’t technically a 24 hour day, it certainly seemed like it was.

The country is located on the Mid-Atlantic ridge with about 200 volcanoes, many of them active, and there are three major glaciers that sit on top of some of these volcanoes. We all remember the eruption under Eyjafjallajökull (“glacier of Eyjafjöll”) in 2010 that disrupted air travel in northern Europe for several weeks; however that volcano is rather minor in Icelandic terms. In the past, eruptions of Eyjafjallajökull have been followed by eruptions of the larger volcano Katla. It is incredibly fortunate that there were no signs of an imminent eruption of Katla following the 2010 eruption.

Anybody that works on climate change knows that volcanic eruptions affect the climate significantly – mainly through the infusion of carbon and ash into the atmosphere. What was new to me was that our tour guide suggested that the continuous melting of the glaciers, as caused by climate change, actually increases the frequency of eruptions of volcanoes underneath the glaciers because of the corresponding reduced pressure on the volcanoes. After coming home I followed up on this and found some support for this theory in scientific literature.

Here are a few photographs to show the landscape:

A “typical” waterfall in the background, with the famous Icelandic horses for scale

A “typical” waterfall in the background, with the famous Icelandic horses for scale

A “typical” landscape of the geothermal energy sources

A “typical” landscape of the geothermal energy sources

A close-up of the geothermal water well

A close-up of the geothermal water well

This impressive storage of geothermal hot water supplies the hot water for the entire capital, Reykjavik. The geothermal hot water is delivered to the communities over distances as large as 50 miles with temperature losses smaller than 2oC (3.5oF) over this distance.

This impressive storage of geothermal hot water supplies the hot water for the entire capital, Reykjavik. The geothermal hot water is delivered to the communities over distances as large as 50 miles with temperature losses smaller than 2°C (3.5°F) over this distance.

There is a large untapped reservoir of hydropower and geothermal hot water available, and saving energy is not presently on the agenda in Iceland. The country is exploring the option of exporting its sustainable energy to the British Isles through an undersea cable. Right now Iceland is using some of the excess available energy to power energy intensive industries such as aluminum smelting and silicon production.

The availability of sustainable energy is such that it is actually most profitable for the aluminum companies to transport the raw material (Bauxite) from Australia to be processed in Iceland.

The photographs also show that there aren’t many trees in Iceland. It was said (again, by the tour guide) that Iceland used to be covered with trees and vegetation, but unchecked sheep grazing and logging for fuel and building material caused a major erosion of the topsoil that made most of the land unable to sustain deep rooted vegetation.

I was hoping to be able to finish the blog with a statement that unlike some of the islands that I have covered after the Mauritius conference (July 2, 2013), Iceland doesn’t need to explore for fossil fuels on its continental shelf. However, whether it needs to or not, it seems to be doing just that.

Some of us are old enough to remember confrontations between Iceland and England in the 1950s and 1970s that became known as the Cod Wars. The confrontations were about fishing rights in the North Atlantic. The conflict ended in 1976 when the United Kingdom accepted the 200 nautical-miles as a fishery zone exclusive to the Icelandic. This 200 mile exclusion zone has now been accepted almost globally as an area in which the country can look for oil and gas reserves.

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