Book Review: Sustainable Energy, by David MacKay

01 Dec 2009Archived News Climate Change Matters

Dr Gordon Weiss, Energetics' Principal Consultant, Process Efficiency, reviews a book which challenges some of the current thinking around energy demand and supply.

“to those who will not have the benefit of two billion years’ accumulated energy reserves”

This is the opening of “Sustainable Energy – without the hot air” by David MacKay, which is available free online from This is a book about numbers; numbers that relate to the energy in the United Kingdom. And whilst many of the numbers may be different, the general principles also apply to Australia.

The book explores the numbers behind energy demand and supply, providing simple calculations and examples so that any reader can figure out the numbers; and to make the situation so clear that any thinking reader will be able to draw striking conclusions.

The first section “Numbers, not adjectives” seeks to answer the question “can we conceivably live sustainably” (ie without fossil fuels). MacKay provides estimates of energy consumption and production arrived at from fundamental calculations, answering such questions as “How much power does a regular car-user consume? How much wind power could we plausibly generate?” In so doing, he develops the renewable energy balance sheet for the UK and demonstrates that current energy demand in the UK cannot be supported by renewable energy sources.

The book moves to exploring the “big idea” ways of reducing demand and increasing supply. It evaluates the potential for better transport, better buildings, new coal technologies, nuclear power etc. Each section describes an element in the energy balance sheet, in an easy to read yet technically satisfying manner making it possible for the non specialist to gain an appreciation of the major issues around the various big ideas. The section concludes with five energy plans for Britain considered technically feasible by 2050 and a cost estimate for a sixth plan which lies roughly in the middle of the first five. The section finishes with a discussion of carbon capture and storage, concluding that it sounds absurd but should be pursued in case things get really bad and it turns out to be our last line of defence.

The final section provides more technical details in support of the calculations in the earlier chapters and there is a massive list of useful data, web links and bibliography. Each chapter ends with details of the ideas in that chapter, sources of data and quotes, and pointers to further information.

“Sustainable Energy – without the hot air” provides a novel insight into our energy future and could help inform the debate around energy supply and demand in an ecologically constrained environment.

David MacKay is a Professor in the Department of Physics at the University of Cambridge, and a member of the World Economic Forum Global Agenda Council on Climate Change.

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