We are all aware of anthropogenic (man-made) global warming. Of course, there are skeptics who insist on ignoring the facts and clinging to their belief that man is too puny to affect the environment. I offer my heartfelt sympathy for them- because they will have to change their outlook drastically in the coming years. People who earnestly think that we can go on burning hydrocarbons and consuming energy at the rate we are now, are really in for a shock. At some point, man will live without fossil fuels.

The material available on this topic is often vague and confusing, as they rarely talk about the amount of fossil fuel remaining beneath the surface of the earth, the amount of carbon emitted when you drive a car for 50 km etc. That’s what David Mackay, Professor of Natural Philosophy, University of Cambridge says – when we talk about Energy and Climate Change, we need “numbers, not adjectives”.

His book, Sustainable Energy – Without the Hot Air (released under many Creative Commons licenses) is an attempt to understand the present day situation, by using numbers in a sensible manner. The book talks about the trends in the UK, but it is not difficult to extend it to any part of the world. It estimates the average energy consumption of a person, in various forms- driving a car, flying, electricity used by gadgets, energy embodied in the stuff one buys etc., compares it to the possible renewable energy sources that can be tapped(very optimistically) and tries to figure out whether our present lifestyles are sustainable. It is a must read for anyone interested in Climate Change and Energy Crisis.

The podcast of a one hour lecture delivered by him, a condensed form of the book, is also available here. All the facts and figures referred to in the talk are there in the book.