On a visit to my parents I was surprised to see a copy of “Sustainable Energy – Without the Hot Air” by David MacKay lying around. My father told me my brother had given him a copy since he had been at Cambridge at the same time as David MacKay. I had heard of the book and read as much as I could whilst I was there.
Dr David McKay was born in 1967 and studied Natural Sciences and Physics at Cambridge University. After carrying out doctoral studies in the States on machine learning he continued his research at Cambridge. This might have be have been it, a good but obscure career in Science if he had not written “Sustainable Energy – Without the Hot Air”.
In this he had a number of brilliant ideas. The first was so simple (but like many innovations you wonder why you have not thought of it yourself). This was to put all our energy use in kWh/day per person (for UK and USA), rather than barrels of oil, or millions of tonnes of oil equivalent etc. The kWh is a unit that even we cannot define is something we are familiar with in our daily lives. The second idea was to consider all our energy use for all we do in kWh. Many books (and I’ve read some of them) simply say we can move over to renewables and that’s it. The problem is as we tried to express in our book its not as simple as that. At the moment carbon fuels and to a certain extent nuclear give us an excess of energy which means we do not have to worry about our energy use for material things which make up our total (hidden) energy demand. Some of the examples he gives are shocking such as newspapers and magazines and aluminium cans (cans need 500W each to make). He produced overall graphs of energy demand and supply in kWh/day per person. When we can to write “No oil in the Lamp” he very kindly gave us permission to reproduce one of these without paying royalties.
In 2009 he was appointed as Chief Scientific officer at the Department of Energy and climate change. Here David McKay came up with another innovation which was an on-line 2050 calculator, free for anyone to use. In it you could come up with your own electricity system and see if you meet the UK climate targets (mandated under the climate change act). You could choose all nuclear/solar etc or any combination thereof and see how far it got you. This was an open source effort written in Ruby that anyone could join in.
Whilst I think David MacKay’s analysis of the problems was spot on, I did not always agree with his solutions. He did not seem to recognise resource limitations which when you are planning longterm you must do. He was very pro nuclear and given all that has happened since with Fukishima and the Hinkley C only confirms my anti-nuclear stance. Indeed in some ways his energy calculator undermined his own arguments. I had several goes with the 2050 calculator and could meet the 2050 climate target using only renewables*. He did seem to recognise Uranium resource limitations, but his way round this was to extract it from seawater. I got hold of one of the papers he cited and in my view he made a mistake in his calculations by a factor of 1000. Uranium has been extracted from seawater on a minute scale but as the concentrations are in the order of parts per billion its simply impracticable. Interestingly he was far more cautious about extracting lithium from seawater and this is a 1000 times more concentrated than uranium.
He also underestimated the speed and the fall in cost of solar or batteries (but has every excuse there), but more worryingly the contribution solar could make to the nations electricity supply. We are now producing whilst not anything like the potential maximum he comes up with but at the same time disproportionately more than we should be in his terms, having barely scratched the surface of our roof and field space. Partly this his caution in considering only the best south facing roofs when in actual fact roofs that face East or West give a reasonable power output. Partly its that he considers fields and the domestic scale and not large commercial roofs (and we have barely started on these).
David McKay came from a strongly Christian background but lost his faith. This background made him strongly aesthetic in his personal life according to some. My last criticism of the his book was that it attempted to keep everything humming along as it is now. What his book confirmed to me was this is not possible and its this that will be the difficult sell. Its sad and shocking when someone dies so young. His contribution to our future energy debate was immeasurable and he will be missed.
* closing the existing nuclear was not an option.