According to official data from the Index Mundi website, global electricity consumption was 17.780 billion kWh in 2011 and 19.090 billion kWh in 2012. Of course, with the increasing population at the global level as well as the expanding infrastructure, the amount of electricity consumed is increasing every year. With such a trend, energy resources are limited and will be depleted in the near future.
On the other hand, the Earth receives an average of 164 watts of solar energy per square meter every day, making it 84 terawatts of power (or 84 billion kWh) per day worldwide. So there is a challenge but there is also a possible solution. Of course, one might think that to use solely solar energy, which would completely replace the use of electricity, would require covering a large amount of the Earth's surface with solar panels. Well, that's wrong.
According to a diploma thesis by Nadine May of the Technical University of Braunschweig titled “Eco-balance of a Solar Electricity Transmission from North Africa to Europe,” the world could be entirely powered by solar energy by placing solar panels in a small area in North Africa.
The three red boxes you can see in the image above show the area that would be enough to cover the demand for solar electricity in Germany (D), Europe (EU-25), and the whole world (Welt).
Of course, this would require installation of the necessary equipment and cable networks and would have some ecological impacts on the ecosystem of the area, which, however, would be many times lower than those from a conventional energy plant. In any case, the benefits would be much greater than any possible environmental effects.