average cost of hydroelectric dams
Hydroelectric power is also very efficient and inexpensive. Modern hydro turbines can convert as much as 90% of the available energy into electricity. The best fossil fuel plants are only about 50% efficient. In the US, hydropower is produced for an average of 0.7 cents per kilowatt-hour (kWh). This is about one-third the cost of using fossil fuel or nuclear and one-sixth the cost of using natural gas, as long as the costs for removing the dam and the silt it traps are not included. Efficiency could be further increased by refurbishing hydroelectric equipment.