Energy Density and Carbon Impact
See also: Energy value of coalThe energy density of coal, i.e. its heating value, is roughly 24 megajoules per kilogram. (approximately 6.7 kilowatt-hours per kg.) For a coal power plant with a 40% efficiency, it takes an estimated 325 kg (720 lb) of coal to power a 100-W lightbulb for one year.
As of 2006, the average efficiency of electricity-generating power stations was 31%; in 2002, coal represented about 23% of total global energy supply, an equivalent of 3.4 billion tonnes of coal, of which 2.8 billion tonnes were used for electricity generation.
The US Energy Information Agency's 1999 report on CO2 emissions for energy generation quotes an emission factor of 0.963 kg CO2/kWh for coal power, compared to 0.881 kg CO2/kWh (oil), or 0.569 kg CO2/kWh (natural gas).
Read more about this topic: Coal
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