Renewable energy is a combination of new energy and renewable energy. It refers to energy used by converting existing fossil fuels or converting them into renewable energy including sunlight, water, precipitation and biological organisms. Renewable energy includes solar power, solar heat, bio, wind and hydro power and new energy includes fuel cells and hydrogen energy. Although there is a disadvantage that the initial investment cost is high, interest in new and renewable energy is increasing as the importance of the depletion of fossil energy and environmental problems is mentioned.