Solar energy can meet all the world's energy demands.

"The Solar Energy resource is enormous, and distributed all over the world, in all countries and also oceans. There is thus an enormous resource available from photovoltaics, which can be used everywhere, and can in principle cover all the world energy demand from a renewable, safe and clean source,” said Daniel Lincot, the chairman of the five-day European Photovoltaic Solar Energy conference held in Valencia.
Lincot, the research director of the Paris-based Institute for Research and Development of Photovoltaic Energy, said solar energy was growing rapidly but still made only a "negligible" contribution to total energy supply. Last year the world production of photovoltaic models represented a surface of 40 square kilometres (16 square miles) while meeting the electrical consumption of countries like France or Germany would require 5,000 square kilometers, he said.
Under current scenarios, Photovoltaic models will represent about 1,000 square kilometers by 2020 accounting for about only 3.0 percent of energy needs in the 27-member European Union, he added.
Over 200 scientists and Solar power experts have signed a declaration calling on the accelerated deployment of photovoltaic power which was launched at the conference. More than 3,500 experts and 715 sector firms took part in the gathering, billed as the largest conference ever organized in the field of photovoltaic conversion of solar energy. Germany and Spain are the world leaders in solar energy power. Germany has 4,000 megawatts of installed capacity while Spain has 600 megawatts.