The efficiencies of modern thermal power stations using the steam cycle can exceed 40% based on lower heatingvalue(LHV),althoughtheaverageefficiencyof the installed stock world wide is closer to 30%. The cost of a modern coal-fired power station with SOx and NOx controls is typically $US1 1300=kWe but less efficient designs with fewer environmental controls are cheaper and therefore often built in developing countries. Costs vary considerably depending on location. Recently, efficienciesof48.5%havebeenreportedand,with furtherdevelopment,by2020theycouldreach55% at costs only slightly higher than current technology (DTI,1999).