David Mackay: A reality check on renewables

How much land mass would renewables need to power a nation like the UK? An entire country’s worth. In this pragmatic talk, David MacKay tours the basic mathematics that show worrying limitations on our sustainable energy options and explains why we should pursue them anyway. (Filmed at TEDxWarwick.) TEDTalks is a daily video podcast of the best talks and performances from the TED Conference, where the world’s leading thinkers and doers give the talk of their lives in 18 minutes (or less). Look for talks on Technology, Entertainment and Design — plus science, business, global issues, the arts and much more. Find closed captions and translated subtitles in many languages at Follow TED news on Twitter: Like TED on Facebook: Subscribe to our channel: