 Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies.Solar energy technologies include solar heating, solar photovoltaics, concentrated solar power and solar architecture, which can make considerable contributions to solving some of the most urgent problems the world now faces.The International Energy Agency projected that solar power could provide "a third of the global final energy demand after 2060, while CO2 emissions would be reduced to very low levels."