This is the fifth study in a series on the future costs of generating electricity. It reviews cost estimates for power plants using nuclear, coal, gas and renewable energy sources. Experts from fourteen OECD countries and five non-OECD countries provided estimated costs for investment, for operations and maintenance, and for fuel for more than 70 power plants. A uniform, consistent method of analysis produces comparable, levelised costs of electricity (cents/kWh). The study also analyses the effects on generation costs of variations in economic lifetime, plant load, and fossil fuel price escalation. An authoritative reference in the field, this publication will be especially useful to electricity system analysts and experts in electric power economics.