Solar energy can be harnessed using various technologies such as solar heating, photovoltaics, solar thermal energy and solar architecture. The two most mature solar technologies are non-concentrated photovoltaic solar panels and concentrated solar power. Emerging solar technologies like concentrated photovoltaic systems, dye sensitized solar cells and solar thermoelectricity still face technical challenges to overcome. Solar power is anticipated to become the world's largest source of electricity by 2050.