What are the main types of renewable energy sources?

Main renewable energy sources include: Solar (photovoltaic for electricity, thermal for heat), Wind (onshore and offshore turbines), Hydropower (dams, run-of-river, pumped storage), Biomass (organic matter for heat or electricity), Geothermal (earth's heat for power or direct use), and Ocean energy (tidal, wave). Each has different characteristics in terms of availability, predictability, capacity factor, and cost. Solar and wind are the fastest-growing renewables, while hydropower provides the largest share of renewable generation.