<http://schema.org/about>
"Yes, it's true that making solar panels creates carbon dioxide, but over the life of a solar installation it produces on average of 30x less CO2 than coal power"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/green-tech/research-innovations/blogs/how-much-co2-does-one-solar-panel-create>