Reference

Land Art Generator Initiative
http://www.landartgenerator.org/blagi/archives/127

EIA - International Energy Outlook 2009-World Energy Demand and Economic Outlook
http://www.eia.doe.gov/oiaf/ieo/world.html

via

世界で利用する電力をカバーするのにどれくらいの太陽電池が必要かを表す地図 - GIGAZINE
http://gigazine.net/index.php?/news/comments/20090830_solar/