Electricity consumption has slowed while the use of natural gas, wind, and solar have become larger portions-- with coal and nuclear becoming less -- of the nation's electricity generation between 2001-2013.
That was one observation of an interesting report issued by the Government Accountability Office this week that looked at the changing ways in which the US generates and uses electricity.
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Here’s a look at some of the key facts of the report, from the GAO:
1. Continuing a long-term trend, growth in electricity consumption slowed from 2001 through 2014. According to the Energy Information Administration data on annual national electricity retail sales—a proxy for end-use consumption—the rate of growth of electricity consumption has slowed in each decade since the 1950s, from growing almost 9% per year in the 1950s, to over 2% per year in the 1980s and 1990s. This decreasing growth trend continued in the 2000s, with electricity retail sales growing by over 1% per year from 2001 through 2007, and fluctuating, but remaining largely flat from that time through 2014.
2. Regarding consumers, industrial electricity consumption has decreased since 2001, while commercial and residential consumption have increased. Specifically, industrial consumption decreased by 4% over the period from 2001 through 2014, and the sector’s share of total electricity consumption declined from 29 to 26%. Meanwhile, residential electricity consumption increased 17%, and commercial consumption increased 25%over this period. Regional electrical consumption varies: The majority of wind and solar electricity generation is concentrated in a few states—in 2013, California and Arizona accounted for over half of electricity generated at solar power plants. Regarding consumption, national retail sales of electricity grew by over 1% per year from 2001 through 2007 and remained largely flat from that time through 2014.
3. Maintaining reliability: System operators, such as utility companies, have taken additional actions to reliably provide electricity to consumers. For example, some regions have experienced challenges in maintaining the delivery of natural gas supplies to power plants. In particular, severe cold weather in the central and eastern U.S. in 2014 led to higher than normal demand for gas for home heating and to generate electricity. Challenges delivering fuel to natural-gas-fueled power plants resulted in outages at some plants.
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4. Prices: Increased gas-fueled generation has influenced electricity prices, with wholesale electricity prices and gas prices generally fluctuating in tandem over the past decade. The effect of the increased use of wind and solar sources on consumer electricity prices depends on specific circumstances.
5. Changes in the economy: Changes in electricity consumption are often closely linked to the economy, according to the EIA. In this regard, the economic recession from late 2007 through 2009 was associated with a large drop in electricity consumption in the industrial sector. Since many industrial operations operate more evenly throughout the year, declines in industrial operations could lead to reduced electricity consumption throughout the year.
6. Efficiency improvements: Overall improvements in the efficiency of technologies powered by electricity—such as household appliances and others—have slowed the growth of electricity consumption,according to EIA. For example, according to EIA, a new refrigerator purchased today uses less than a third as much electricity as one purchased in the late 1970s, despite the larger size of today’s refrigerators.
7. Changes in the uses of electricity: Consumer uses of electricity have changed over the last decades, affecting the nature of electricity consumption. For example, the growing use of computers and home entertainment devices has increased the use of electricity. In addition, air conditioning has become more widely used in U.S. households. As a result, a heat wave—often associated with peak levels of electricity consumption—may lead to more electricity consumption during peak per periods than in the past.
8. Natural gas: Generating capacity and actual generation from natural-gas-fueled power plants increased across the nation from 2001 through 2013, with different regions seeing varying levels of growth, according to our analysis of SNL data. Natural-gas-fueled generating capacity increased by about 181,000 MW during this period, and accounted for 72% of the new generating capacity added from all sources. This trend continued in 2014 with the addition of approximately 4,000 MW of gas-fueled generating capacity. This increase in gas-fueled capacity resulted from the construction of about 270,000 MW during this period offset by a smaller amount of retirements. Regarding actual generation, electricity generated from natural-gas-fueled power plants generally increased throughout this period, with a pronounced jump from 2011 through 2012 when generation increased by about 21%.
9. The wind: Generating capacity and actual generation from wind and, to a lesser extent, solar power plants increased from 2001 through 2013, with most of the increase occurring since 2007. GAO has have previously found that various federal and state actions have contributed to increases in wind and solar power plant capacity, including financial supports and state renewable portfolio standards. These increases led to wind and, to a lesser extent, solar accounting for a larger share of the nation’s energy mix, increasing from just over 0% of electricity generation in 2001 to 4% in 2013. Regarding wind, generating capacity increased about sixteen fold over this period, with 57,000 MW of capacity added from 2001 through 2013 and wind’s share of total generating capacity increasing from near 0% in 2001 to 5.4% in 2013.
10. The wind part 2: Wind plants operate less intensively than some other sources because wind power plants only generate electricity when the wind is blowing. As such, wind’s share of the nation’s actual generation increased from just over 0% in 2001 to about 4% in 2013. Electricity generation from wind increased by over 160million MWh from 2001 through 2013, the second largest increase in actual generation of all energy sources after natural gas. Most of this increase, 136 million MWh (or 84%of the total increase), occurred since 2007. Electricity generated from wind is concentrated in a few states; 74% of total electricity generated from wind came from 10 states in 2013.
11. The sun: Regarding solar, generating capacity increased by about 7,000 MW, or about eighteen-fold, from 2001 through 2013 at larger power plants with capacities of at least 1 MW. This trend accelerated in 2014 with the addition of over 3,000 MW of solar generating capacity, and total solar generating capacity reached about 10,000 MW. Regarding actual generation, electricity generated at large solar power plants increased about 7 fold—by about 5 million MWh—from 2001 through 2013. The average utilization of solar power plants fluctuated over this period between 16 and 25%. Despite the growth in solar capacity and generation, large solar power plant generation contributed less than 0.2% of total electricity generation nationwide in 2013. More so than wind generation, generation from solar power plants was concentrated in a small number of states. For example, California and Arizona accounted for over half of electricity generation from large solar power plants in 2013.
12. The coal case: Generating capacity and actual generation from coal-fueled power plants declined from 2001 through 2013 as plants retired in some cases, witnessed changes in their usage patterns, according to our analysis of SNL data. Coal-fueled electricity-generating capacity was stable for most of this period, but declined over the last couple years as aging plants retired and little new capacity was added. Specifically, from 2001 through 2013, about 29,500 MW of coal-fueled generating capacity retired, with about 75 percent of those retirements occurring from 2009 through 2013.
13. Nuclear: Generating capacity and actual generation from nuclear power plants both increased from 2001 through 2013, but the share of nuclear in the national electricity mix declined because other sources increased by a larger amount, according to our analysis of SNL data. No new nuclear power plants were built during this period, and four nuclear power plants retired in the last 2 years, accounting for about 4,200 MW of capacity. In 2013 and 2014, four nuclear power plants with five nuclear generating units retired. However, nuclear generating capacity increased by 5 percent from 2001 through 2013 because of capacity increases at some existing plants as owners upgraded equipment or undertook other changes.
14. Data on solar generating capacity and actual generation do not include distributed solar installations, such as capacity installed on household or commercial rooftops—known as distributed generation. Data from an industry association show that distributed solar generating capacity has increased to reach over 8,500 MW as of the end of 2014—compared to about 10,000 MW that was installed at larger solar power plants. The electricity generated at such distributed generation sites is not generally measured or managed by the system operator. Nonetheless, it can be a significant portion of the generation mix in some regions. For example, according to the largest utility in Hawaii, solar systems had been installed on 12% of residential consumer sites in Hawaii as of the end of 2014, and on the island of Oahu, this capacity was equivalent to about 25%of the island’s peak electricity needs.
15. Hydropower: Generating capacity and actual generation from hydropower plants increased from 2001 through 2013, by 3,600 MW and 68 million MWh respectively. Generation from hydropower plants varies from year to year based on a region’s weather, particularly the amount of rain or snow.
16. Generating capacity and actual generation from other sources—including oil, biomass, and geothermal together—declined overall from 2001 through 2013. This decline was primarily driven by declines in oil-fueled power plants, where generation declined by over 80% and average utilization declined over the period. Two regions, New England and Florida, accounted for a large portion of the decline in oil-fueled power plant generation.
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