This week, guest bloggers Kyle O’Carroll, Daniel Kruglyak, and Vikash Tewari are taking over the Climate Change Fork blog. We are undergraduate students at Brooklyn College, class of 2020. We are all majoring in physics with minors in biochemistry, chemistry, and chemistry respectively. The focus of our blog is to evaluate nationwide electrical efficiency and to examine how different forms of energy are used to produce electricity. We will discuss how these energy sources have changed over time.
Before we get into the complexities of our discussion, it is necessary for us to present some of the definitions which we will build upon throughout this blog. The most critical aspect to understand for our discussion is the difference between electricity and energy. For our purposes, we will define energy in terms of the various sources which are used to generate electricity.
Different energy sources include coal, oil, natural gas, hydroelectric power, solar, biomass, nuclear, geothermal, and wind. These can largely be broken into two different categories: renewable and nonrenewable. We take a renewable energy source to mean any method of electricity production which uses an element of our natural environment in a way that does not decrease its supply as a result of that production. Renewable sources include hydroelectric power, solar, biomass, geothermal, and wind energy. On the other hand, nonrenewable sources consist of any electricity sources which have a finite quantity and can decrease with continued use. These nonrenewable sources include coal, oil, natural gas, and nuclear energy. While nuclear energy can technically be classified as either renewable or nonrenewable, depending on the definition used, we will classify it here as nonrenewable. This is because the uranium used in nuclear energy plants to create electricity depletes over time.
It is important to note that renewable and nonrenewable sources have substantial differences both in their impacts on the environment and in their carbon production. All renewable sources produce negligible carbon dioxide emissions, whereas nonrenewable sources—with the exception of nuclear energy—create high levels of them. Studies suggest that these carbon emissions contribute to an increase in the global temperature, which in turn contributes to a multitude of global phenomena including droughts, typhoons, hurricanes, the melting of the polar ice caps, rising sea levels, and many other natural cataclysms.
We must recognize that the electricity which we use every day is created by different sources of energy and that they each contribute different amounts of carbon to the atmosphere. Each country and, in America, each state, has different methods of producing the electricity that will be used by the general population. It is useful to identify how different places generate electricity and how that has changed over time. Something as simple as leaving your television on in your home overnight can contribute to the degradation of the environment, depending on how the electricity which powers the television was generated. Recognizing the effects we have on the environment—even when carrying out everyday processes—is a vital step in working towards creating a cleaner future. We need to be cognizant of our actions so we can do our part to help mitigate climate change.
Many countries came together under the 2016 Paris Climate Agreement, promising to make a push to cut emissions by 2025. Countries such as Sweden, Costa Rica, Nicaragua, Scotland, and Germany have shifted to almost 100% renewable energy to produce their electricity (Council, 2019). Shifting to non-carbon-emitting energy sources for production of electricity is one major way that a country can help halt emissions and reduce the effects of global warming. America has not made a complete shift toward renewable energy sources and it is severely hurting the attempt to reach our global emission goals. We should recognize, however, that while America as a whole is not moving towards renewable sources, there are some states which use them almost exclusively to generate their electricity.
Figures 1a and 1b show two examples of outliers in electricity production in the United States from the period of 2001 to 2017. Idaho is one state that leads in clean electricity production; it produced over 80% of its electricity from renewable sources. Hydroelectric power has decreased recently in Idaho due to droughts but the state’s use of wind has increased as a result. Meanwhile, on the other side of the spectrum, West Virginia produces 93% of its energy from coal. In 2015, lobbyists repealed its renewable energy standard which would have required 25% of its electricity to come from renewable sources.
Figures 1a & 1b – These charts show the change in energy production over the years (2001-2017) of Idaho (above) and West Virginia (below)
Local communities in the US need to work towards policies which shift their electricity production. As a whole, America should look to countries like Sweden for inspiration for the coming years and implement nationwide reform to our current policies.
In order to discuss America’s impact on the climate, we focused on evaluating our country’s efficiency in electricity use as well as the effect of this efficiency on the wellbeing of the planet. We will calculate efficiency as electricity generation versus gross domestic product (GDP). GDP as defined by the Bureau of Economic Analysis is a comprehensive measure of US economic activity. GDP is the value of the goods and services produced in the United States. The growth rate of GDP is the most popular indicator of the nation’s overall economic health. By evaluating electricity generation per GDP, we are able to discuss America’s efficiency of use of generated electricity to promote its economic products. The factor of electricity/GDP correlates to the IPAT equation, where we take:
This equation is critical in the discussion of climate change; it is the primary determining factor of worldwide CO2 production at a given time. The factor (Energy/ GDP) is used for representation of energy intensity and is where we derived our definition of electrical efficiency. To identify the change in America’s efficiency over time, we looked through multiple data sources and compiled graphs which represent the historical trends of the country’s production.
As we can see, the chart displays a negative trend, which implies that the GDP is rising faster than electricity production. We define efficiency in terms of effective use of electricity to produce GDP. The y-axis shows the required amount of watt-hours to produce a dollar in GDP. This means we can produce the same amount of GDP with less electricity. This data shows us that in the last 20 years the efficiency of the United States has increased.
Figure 3 – Ratio of CO2 to Electricity Generation in the US, 1998-2017
(“State Electricity Profiles – EIA” 2016) & (“Carbon Dioxide Emissions From Energy Consumption – EIA” 2019)
In plotting the ratio of carbon emissions to electricity generation over time we are able to note that there has been an overall negative slope. This indicates that America is moving in the right direction. Over the last 20 years we have decreased the amount of carbon produced in generating the same amount of electricity. This is due to an increase in cleaner energy sources such as renewable energy over the past 2 decades, as shown in the next graph.
Figure 4 – US electricity generation by major energy source, 1950-2018
As we see in the electricity generation by major energy sources in the US, over the last 20 years coal use has decreased and renewable energy sources have seen an increase. This explains why carbon emissions per megawatt-hour production have decreased. Despite recent false claims about wind power causing cancer, wind power is a great source of clean, renewable energy.
Many countries are making the effort to move towards cleaner energy and America should continue to follow suit. Throughout recent years, America has been slowly reducing carbon emissions by producing electricity using cleaner energy sources. However, these changes have been too slow and insignificant. While our data shows that America has moved towards cleaner electricity production and has become more efficient, we should not sit back and allow the government to be pleased with these minor successes. It will take a long time to completely switch to clean/renewable energy altogether so while clean electricity production is a good start, large-scale policy changes need to be made in all aspects of our society. In order to reach the goals set out in the Paris Climate Agreement, and for the good of our planet, we need to continue to make bold strides to reduce our carbon emissions and protect our planet.
- Council, C. (2019, January 14). “11 countries leading the charge on renewable energy – Climate Council.” Retrieved from Climate Council website: https://www.climatecouncil.org.au/11-countries-leading-the-charge-on-renewable-energy/
- Electricity in the United States – Energy Explained, Your Guide To Understanding Energy – Energy Information Administration. (2019). Retrieved from EIA.gov website: https://www.eia.gov/energyexplained/index.php?page=electricity_in_the_united_states
- GDP (current US$) | Data. (2016, December 31). Retrieved from Worldbank.org website: https://data.worldbank.org/indicator/NY.GDP.MKTP.CD?locations=US
- “How to Cut U.S. Emissions Faster? Do What These Countries Are Doing.” (2019, February 13). The New York Times. Retrieved from https://www.nytimes.com/interactive/2019/02/13/climate/cut-us-emissions-with-policies-from-other-countries.html
- Popovich, N. (2018, December 24). “How Does Your State Make Electricity?” The New York Times. Retrieved from https://www.nytimes.com/interactive/2018/12/24/climate/how-electricity-generation-changed-in-your-state.html
- State Electricity Profiles – Energy Information Administration. (2016). Retrieved April 26, 2019, from EIA.gov website: https://www.eia.gov/electricity/state/
- Table 12.6 Carbon Dioxide Emissions From Energy Consumption: Electric Power Sector (Million Metric Tons of Carbon Dioxide). Retrieved from https://www.eia.gov/totalenergy/data/monthly/pdf/sec12_9.pdf