Carbon-neutral fuel the carbon dioxide in flue gas emissions from power plants would eliminate their greenhouse gas emissions, although burning the fuel in vehicles would release that carbon because there is no economical way to capture those emissions. This approach would reduce net carbon dioxide emission by about 50% if it were used on all fossil fuel power plants. Most coal and natural gas power plants have been predicted to be economically retrofittable with carbon dioxide scrubbers for carbon capture to recycle flue exhaust or for carbon sequestration. Such recycling is expected to not only cost less than the excess economic impacts
Carbon sink gasification technology, where it is estimated to raise energy costs for households in the United States using only coal-fired electricity sources from 10 cents per kW·h to 12 cents. Currently, capture of carbon dioxide is performed on a large scale by absorption of carbon dioxide onto various amine-based solvents. Other techniques are currently being investigated, such as pressure swing adsorption, temperature swing adsorption, gas separation membranes, cryogenics and flue capture. In coal-fired power stations, the main alternatives to retrofitting amine-based absorbers to existing power stations are two new technologies: coal gasification combined-cycle and oxy-fuel combustion. Gasification first produces a "syngas"