According to the 2007 DOE report on carbon capture technology it would seem that the government things that carbon capture is more expensive than renewable energy.
Step 1 (page 5)
The overall goal of the Carbon Sequestration Program is to develop, by 2012, fossil fuel conversion systems that achieve 90 percent CO2 capture with 99 percent storage permanence at less than a 10 percent increase in the cost of energy services.
Step 2 (page 9)
It is believed that a 10 percent cost of electricity (COE) increase would significantly reduce impact to the economy. This level will also enable fossil fuel systems with CO2 capture and sequestration to compete with other power generation options to reduce the GHG intensity of energy supply, including wind, biomass, and nuclear power.
Presumably, then, DOE believes if you increase the cost of electricity from coal more than 10%, it can no longer compete with alternatives. (Okay, so they omitted solar and included nuclear, but hang on.)
Step 3 (page 17-18)
Preliminary analysisâ€¦indicatesâ€¦that CO2 captureâ€¦.could raise the cost of electricity from a new supercritical PC power plant by 65%, from 5.0 cents/kWh to 8.25 cents/kWh.
Analysisâ€¦.show that CO2 capture and compression raisesâ€¦..the cost of electricity from a newly built IGCC power plant by 30%, from an average of 7.8 cents/kWh to 10.2 cents/kWh.
Which would seem to be above the 10% measure listed above, meaning that carbon capture technology would make coal power more expensive than wind biomass or nuclear, at least according to their numbers. They left solar out, but with recent trends in investment by large players (Google), and the announcement of cheap solar just around the corner it would seem to indicate that solar is going to be cheap long before clean coal is. The government also recently shut down Future-Gen (Bush’s “clean coal” plan) because it costs too much. In other news wind power went crazy last year with a 45% increase.