Tanada wrote:drwater wrote:Tanada saidSwitching to Natural Gas isn't the be all end all either, a ton of methane fully burned would cost you about as much as the coal.
Natural gas actually is far better than coal:
Pounds of CO2 emitted per million British thermal units (Btu) of energy for various fuels:
Coal (anthracite) 228.6
Coal (bituminous) 205.7
Coal (lignite) 215.4
Diesel fuel and heating oil 161.3
Natural gas 117.0
Add on top of that the fact that combined cycle natural gas power plants are closer to 60% thermodynamic efficiency versus low 30%s for single cycle coal plants, and you have a huge advantage for natural gas versus coal with a carbon tax.
You can't just skip right over the fact that natural gas to produce that Million Btu's of heat is more than three times as expensive as the coal to do the same job. You also can't compare a 70 year old lump coal steam plant with lousy 30 percent efficiency with the vast majority that are powdered coal fluidized bed combustion units. They started building that style in the 1970's for Pete's sake! A fluidized bed coal plant is 40 to 45 percent efficient. You also can not assume the Natural Gas is all being burned in combined cycle system to provide that 60 percent efficiency, a great many of them are simple gas turbine units intended for peaking use that have over time been left running more and more to make up for shortfalls in baseload power. Peaking plants and those simple baseload plants do not even have the Combined Cycle portion of the plant built, so it is literally impossible for them to achieve CCGT efficiency levels.
See the link above. The EIA numbers drwater posted already include power plant efficiency. So that's the amounts of CO² actually emitted.