Electricity produced in the daytime, stored in batteries for use during the night or on cloudy days. Solar generated electricity used to split water into hydrogen and oxygen. Hydrogen can be burned or used in fuel cells. Waste product is water. Hydrogen can be produced from any hydrocarbon or from solar energy.
Fuel cells remove electrons from hydrogen to make electric current.
Windmill is 10 stories tall with 80 foot blades. Wind driven blade movement generates electricity. Wind power is cheap and effective in rural areas such as the great plains. Usually needs a dam and reservoir to store enough water for constant power generation. But dams can damage the environment.