Reducing GHG Emissions by Co-Utilization of Coal with Natural Gas or Biomass

Abstract

Energy reserves price and security of supply issues are discussed in the context of the prospects for coal and policies to reduce greenhouse gas (GHG) emissions. Coal is projected to remain a major source of energy, with most of the demand growth in developing countries. Currently available power-generating technologies, deploying coal with natural gas or biomass, are examined. Examples of successful, partial substitution of coal by other fuels in power stations are highlighted, including the GHG emissions reductions achieved as well as the costs where available. Among various options, hybrid gasification and parallel cofiring of coal with biomass and natural gas appear to have the greatest potential to reduce GHG emissions. Much may also be achieved by cofiring, reburning, and repowering with gas turbines. The best method differs between different power systems. Co-utilization of biomass with coal is a least-cost option to reduce GHG emissions where the fuel prices are comparable, usually due to subsidies or taxes. The role of biomass is likely to increase due to greater use of subsidies, carbon taxes, and emissions trading within the context of the Kyoto Protocol. This should provide opportunities for clean coal technology transfer and diffusion, including biomass co-utilization. 32 refs., 1more » fig., 3 tabs.« less