Sustainable Energy - Without the Hot Air: Volume 2

by David J.C. MacKay

Book Overview

The enlightening, best-selling book on understanding sustainable energy and how we can make energy plans that add up.

If you've ever wondered how much energy we use, and where it comes from - and where it could come from - but are fed up with all the hot air and 'greenwash', this is the book for you. Renewable resources are 'huge', but our energy consumption is also 'huge'. To compare 'huge' things with each other, we need...

• Format: Paperback
• Language: English
• ISBN: 0954452933
• ISBN13: 9780954452933
• Release Date: January 2009
• Publisher: Uit Cambridge Ltd.
• Length: 384 Pages
• Weight: 2.20 lbs.
• Dimensions: 0.8" x 8.4" x 8.1"

Customer Reviews

Great book...

... written in terms a layman can understand. Also, this book is available for free in html and pdf on his website withouthotair dotcom.

Essential purchase

I work for an environmental watchdog in New Zealand. I flicked through the first few pages of "Sustainable Energy - without the hot air" as it sat on a colleague's desk, took it back to my own desk and read it for two hours straight, got online and bought my own copy. It's that good. For a start, this is how environmental science should be communicated; crystal clear text and honest graphs, with simplified theory and ballpark calculations that anyone can follow, backed up by empirical data as a check on results, real examples, frequent references, and explanations of limitations. But the thinking behind it is every bit as good. MacKay is entirely pragmatic about energy supply and demand, never preachy, and he is game enough to admit when his results surprise even himself. If he is cautiously optimistic in his conclusions, it is because he has laid out a number of justifiable options. Buy it. Better still, buy it and read it.

A stimulating, numerate guide to alternative energy

Prof MacKay's starting point is that there is a great deal of vague flummery talked about energy production and consumption. It is easy to make vague claims of "huge" potential green sources or to obsess over what turn out to be very minor energy savings. His goal in this book is to have a hard-nosed discussion of real numbers, so that there can be a more sensible discussion of options. He avoids making explicit recommendations, but his one continual plea is that we create a plan that "adds up" rather than merely reflecting wishful thinking. The world currently consumes enormous quantities of fossil fuel, so any viable alternative plan also has to deal with very large numbers, either as savings or as alternate sources. MacKay writes in a very readable and entertaining style. But he is also very careful to explain his numbers and to build his scenarios from the ground up. I found his analyses convincing and stimulating. Sometimes more detailed or more mathematical analysis is pushed off to supplementary appendices, but those are also well worth reading. I learned many things. One key factor I hadn't appreciated was the enormous land areas required for renewable sources, such as wind, solar, biofuel, or geothermal to make a substantial difference. For example, MacKay calculates that it would probably require 10% of the UK's surface to be dedicated to wind farms in order to make a significant contribution to the UK's current energy needs. Even larger areas are required to generate meaningful quantities of biofuel. If an area the size of Africa were dedicated to growing biofuel, that might only replace a third of current world oil needs. But MacKay also points out there may be places where building vast energy farms makes sense. For example, a 20,000 square km solar power farm in the Sahara could be one way to meet the UK's energy needs. MacKay explains how technologies such as electric cars or heat pumps reduce energy needs, independent of how the electricity is generated. He shows us that because electric motors are extremely efficient, burning oil in a central power plant and using the electricity to run an electric car actually requires much less energy than traditional cars. Similarly, he shows how using a central electric power station to power home heat pumps is a significantly more efficient way to heat houses than burning gas or oil at the house. (I had definitely not understood this before!) MacKay would prefer we use green technology to create the electric power, but it is interesting that even using fossil fuel power stations, electric cars and heat pumps still reduce overall fossil fuel consumption. In his concluding chapters, MacKay outlines several possible plans that "add up". All of them have significant negatives, either through reliance on nuclear power, or enormous environmental impact, or enormous expense. He doesn't pick a winner from among these options, but he emphasizes that we need to chose a plan rathe

A Must Read if discussing sustainable or renewable energy

This book is an essential resource for understanding energy policy as it relates to conservation and to renewable resources. I've just been listening to yet another "news" report pointing out that compact fluorescent light bulbs don't save much energy because an incandescent light bulb will also heat your house. Coincidentally I had just read the part of this book dealing with this myth, so I was able to confidently mutter under my breath "true, but only in the winter (when you need the heating) and only if you are heating inefficiently using electricity." This book puts real numbers to a lot of hand-waving arguments which are used to justify grandiose claims made for different renewable energy sources or to imply that we could save the world if we all just unplugged our mobile phone chargers. Some of the arguments stand up when the numbers are put in, but many don't. When you see what the numbers are, it becomes evident how unrealistic and ineffectual many of the proposals are. Is it worth unplugging a power block when not in use? Can planes be made more efficient? How much space would solar farms or a wind farms need to occupy to meet our energy needs? How much agricultural land would be required for bio-diesel? All these questions (and many more) are answered. What makes this book really stand out is that it converts energy amounts to comprehensible units (kilowatt-hours per person per day), supplies copious references for the numbers used, and provides the calculations on which the arguments are based. (Detailed calculations are presented in appendices for the math-averse and should be accessible to anybody with a basic knowledge of physics). Note. Although this book is primarily aimed at a UK audience (energy consumption figures are based upon UK patterns, and land use proposals are related to UK locations), the discussions are of global applicability.

Do the numbers!

This book is essential for anyone thinking about energy policy. It excels because MacKay does not espouse one specific solution, but rather teaches the reader how to create solutions and evaluate them. He emphasizes that the numbers must add up -- total energy production must equal total energy consumption. In a way the book is very simple. He leads the reader by the hand in estimating the energy requirements of society - transportation, heat, food, gadgets, and so on. He similarly helps you make credible estimates of achievable production from sources such as sunlight, tides, hydro, nuclear, wind, coal, and oil. Like a good physicist, MacKay is able stand back and estimate these numbers top-down from first principles, with just enough depth to generate numbers that are credible to you and good enough for policy making. The charts, graphs, tables, and pictures are extensive and clear. If you have a particularly loved energy source [wind?] or a particularly hated one [coal?] you can "do the numbers" and build your own energy policy. The only requirement is that the numbers add up!