I have just found out about this video from TEDxWarwick in March 2012, where Professor David MacKay delivered a very interesting speech about sustainable energy, and how they cannot match the requirement of energy that our current society has today and tomorrow.
Professor MacKay, well known for his great book “Sustainable Energy – without the hot air”, has a great quote in his speech:
“I love renewables, but I am also pro-arithmetic” -David MacKay
Click on the book cover to go to the book website and learn more about sustainable energy by reading the free book from Prof. MacKay:
http://www.youtube.com/watch?v=-5bVbfWuq-Q