User:Milton Beychok/Sandbox
| Energy Supply Sources | TW | MWh | % |
|---|---|---|---|
| Coal-based | 4.0 | 35×109 | 26.9 |
| Gas, oil, nuclear and other | 10.8 | 95×109 | 73.1 |
| Total supply sources | 14.8 | 130×109 | 100.0 |
| Electricity generation component of the total energy supply sources | |||
| Coal-fired generation | 0.80 | 7×109 | 5.4 |
| Total generation | 2.05 | 18×109 | 13.9 |
Carbon dioxide emissions
To better understand the discussion of carbon dioxide emissions from conventional coal-fired electricity generation plants, the adjacent table provides a perspective on the total global energy supply sources. In 2005, coal-based energy sources constituted 26.9% of the total energy supply sources.
As shown in the table, the total electricity generation (from gas, oil, coal, nuclear, biomass, hydro, wind, solar, geothermal and other power plants) amounted to 13.9% of the total energy supply sources and the coal-fired power plant portion of the electricity generation amounted to 5.4% of the total global energy supply sources.
The emissions from conventional coal-fired power plants include carbon dioxide (CO2) which is the major component of the combustion flue gases produced by burning coal. Carbon dioxide is not a pollutant in the traditional sense and it is essential for all plant life on Earth through photosynthesis. However, carbon dioxide is a greenhouse gas considered to have a major role in global warming. It is the most abundant anthropogenic (human caused) greenhouse gas in the Earth's atmosphere.
In 2005, the total carbon dioxide emissions from all sources to the atmosphere were about 28 Gt (28×109 tonnes or 109 metric tons) and approximately 41 percent those emissions were from coal-based energy supply sources.[1][5]
Carbon dioxide emissions from coal-fired power plants
Carbon dioxide emissions for coal-fired power plants will vary significantly because the those emissions are a function of the coal's carbon content and the plant's thermal efficiency. The coal's carbon content may range from about 50 weight percent for lignite coal to 90 weight percent for anthracite coal and the plant's thermal efficiency may vary from 32 to 42 percent.
A study of the future of coal, developed at the Massachusetts Institute of Technology (MIT)[6] states that, as an average, a 500 MW coal coal-fired power plant produces 3 million tons of carbon dioxide per year. That amounts to a carbon dioxide emission factor of 0.62 kg/kWh. Other sources in the literature range up to 1.0 kg/kWh and, in fact, an emission factor of 0.96 can be derived from 1998 data available for all the coal-fired power plants in the United States.[7]
Assuming an emission factor of 1.0 kg/kWh, the carbon dioxide emissions from the global total of 7×109 MWh of coal-fired power plants is estimated as 7 Gt.
The technology for carbon capture and storage of emissions from coal fired power stations is not expected to be available on a economically viable commercial scale by 2020.
- ↑ 1.0 1.1 International Energy Association, 2006, Key Energy Statistics
- ↑ International Energy Outlook 2008; Highlights (Energy Information Administration, U.S. DOE)
- ↑ International Energy Outlook 2008: Chapter 5 (Energy Information Administration, U.S. DOE)
- ↑ BP Statistical Review of World Energy, June 2006 (British Petroleum website)
- ↑ Energy-Related Carbon Dioxide Emissions: Chapter 7 (Energy Information Administration, U.S. DOE)
- ↑ Cite error: Invalid
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