Title: Coal power in the United States
Content:   Coal power in the United States generates about 20% of the country's electricity. It accounted for 39% of production at utility-scale facilities in 2014, 33% in 2015, 30.4% in 2016, 30.0% in 2017, 27.4% in 2018, 23.5% in 2019, and 19.3% in 2020. Coal supplied 12.6 e15Btu of primary energy to electric power plants in 2017, which made up 91% of coal's contribution to US energy supply. Utilities buy more than 90% of the coal consumed in the United States. In 2019 there were 241 coal powered units across the United States. Coal plants have been closing at a fast rate since the 2010s due to cheaper and cleaner natural gas and renewables. Coal 
Title: Coal power in the United States
Content:  The average share of electricity generated from coal in the US has dropped from 52.8% in 1997 to 27.4% in 2018. In 2017, there were 359 coal-powered units at the electrical utilities across the US, with a total nominal capacity of 256 GW (compared to 1024 units at nominal 278 GW in 2000). The actual average generated power from coal in 2006 was 227.1 GW (1991 TWh per year), the highest in the world and still slightly ahead of China (1950 TWh per year) at that time. In 2000, the US average production of electricity from coal was 224.3 GW (1966 TWh for the year). In 
Title: Energy policy of the United States
Content:   America is self-sufficient in coal. Indeed, it has several hundred years' supply of it. The United States trend in coal use has been rising from 1950 through 2007, when coal production and consumption more than doubled. The population of the US has almost doubled in this time period as well, while the per capita energy use has been declining since 1978. Most electricity (52% in 2000) in the country was historically generated from coal-fired power plants: in 2006, more than 90% of coal consumed was used to generate electricity. In 1950, about 19% percent of the coal consumed was for electricity generation. However, subsequent to 2007, coal-fired electricity began to decline, and in 2018, just 27.4% of US electricity was generated from coal. In terms 
Title: Coal mining in the United States
Content:  The United States has 477 billion tons of demonstrable reserves. The energy content of this coal exceeds that of oil and gas.
Title: Coal mining in the United States
Content:  In 2013, 92.8 percent of US internal coal consumption was for electricity generation. Other uses were industrial (4.7 percent), coke manufacture (2.3 percent), and commercial and institutional (0.2 percent). In 2016, the EIA calculated that coal would provide 30% of electricity generation nationwide with natural gas providing 34%, nuclear, 19%, and renewables, 15%. Both the tonnage of coal used for electricity (1047 million short tons) and the amount of US electricity generated from coal (2020 TWh) peaked in 2007. By 2015, electrical generation from coal had declined to 1360 TWh and 966 TWh in 2019, as coal's share of total electrical generation in the US fell from 48.5 percent in 2007, to 
Title: Fossil fuel regulations in the United States
Content:  Along with other fossil fuels, coal is a major energy resource for the U.S. Most of the energy supplied by coal production is consumed by the electric power sector. Due to competition with renewable energy and natural gas, coal production has been declining since 2008. Currently the U.S. occupies five major basins or regions where coal is produced. The U.S. Energy Information Administration released coal production data of 2016 in January, reporting a 17% decrease from 2015 levels. As coal is projected to remain a key energy resource, regulations concerning environmental pollution increase.
Title: Coal mining in the United States
Content:   Coal mining in the United States is an industry in transition. Production in 2019 was down 40% from the peak production of 1171.8 e6short ton in 2008. Employment of 43,000 coal miners is down from a peak of 883,000 in 1923. Generation of electricity is the largest user of coal, being used to produce 50% of electric power in 2005 and 27% in 2018. The U.S. is a net exporter of coal. U.S. coal exports, for which Europe is the largest customer, peaked in 2012. In 2015, the U.S. exported 7.0 percent of mined coal. Coal remains an important factor in the 25 states in which it is mined. According to the U.S. Energy Information Administration (EIA), in 2015, Wyoming, West Virginia, Kentucky, Illinois, and Pennsylvania produced about 639 e6short ton representing 71% of total 
Title: Coal mining in the United States
Content:  percent in 2015, to 23 percent in 2019, and 19% in 2020. Most of the decrease in coal electricity was offset by an increase in generation from natural gas-fired power plants. In 2006, there were 1493 coal-powered generating units at electrical utilities across the US, with total nominal capacity of 335.8 GW (compared to 1024 units at nominal capacity of 278 GW in 2000). Actual power generated from coal in 2006 was 227.1 GW (1,991 TWh per year), the highest in the world and still slightly ahead of China (1,950 TWh per year) at that time. In 2000, US production of electricity from coal was 224.3 GW (1,966 TWh per year). In 
Title: Energy policy of the United States
Content:  the production of energy from domestic sources, from 1885 through 1951, coal was the leading source of energy in the United States. Crude oil and natural gas then vied for that role until 1982. Coal regained the position of the top domestic resource that year and again in 1984, and has retained it since. The US burns 1 billion tons of coal every year. Concern for climate change has led to a call for a moratorium on all coal consumption, unless carbon capture is utilized. Coal is the largest potential source of CO2 emissions. Integrated Gasification Combined Cycle (IGCC) is the cleanest currently operational coal-fired electricity generation technology. FutureGen is an experimental US research project to investigate the possibility of sequestering IGCC CO2 emissions underground.
Title: Synthetic fuels in the United States
Content:  The United States has 26% of Earth's known coal reserves. This is sufficient to last hundreds of years by the lowest estimates and accounts for 90% of U.S. energy reserves. Coal is a fossil fuel and as such is therefore subject to possible depletion within a few hundred years. In terms of energy obtained, coal peaked in 1998 and though production volumes have increased, the net energy has not, which could be explained by decreasing production of high quality coal, such as bituminous and anthracite. U.S. reserves are approximately 45% bituminous and anthracite. The energy value of all the world's known recoverable coal is 27 zettajoules, which is expected to last 164 years. (See "Coal") Of 

Question: how much energy does coal produce in the us?
Answer: 16.5 quadrillion BTUs.
30.4%.