A kind of renewable energy：the solar cell(太阳能电池) Are the electric cars environmentally friendly? Coal-fired power stationSolar power stationIf the electricity comes from renewable energy rather than Coal-fired power station,I think these eletric cars are environmentally friendly.Not environmentalenvironmental Solar cells can provide electric power ,which is safe and clean. The solar cell has achieved great development and gained wide application at present. The solar cell has achieved great development and gained wide application at present.Solar Impulse II,in 2015 The solar cell has achieved great development and gained wide application at present. The solar cell has achieved great development and gained wide application at present. As we all know,now many countries in Afirca lack of power stations. So many families in rural areas do not have power.How to deal with the problem? The good solution is to install solar cells. Since then people can work at night ;children have more time to study. Solar energy is very rich on the earth. We assume that the following. 40 times0.05% earth's surface 10% conversion ratessolar cells’ areasThe world energy consumption？ Why can solar cell reduce emissions?The areas of a standard football field for solar cell 400 tons of coal for power-station13 trucksone yearto reduce 6 trucks of carbon dioxide How many sizes we need for the solar cells that can provide enough power for a family one day? We need only less than 3 square meters of solar cell panels. If a family generates more power than it needs,it can sell the excess electricity to power company. The excess electricity If a family generates more power than it needs. it can sell the excess electricity to power company If a family generates more power than it needs. it can sell the excess electricity to power company Steve Jobs once said,“stay hungry,stay foolish (求知若饥,虚心若愚).”I want to say “stay environmental,stay sustainable.” 。