British scientist gets serious on making the energy numbers add up

David MacKay, author of “Sustainable Energy Without the Hot Air” is a number-cruncher par excellence and is spending much of his personal energy using the power of figures to get people thinking about what plans we should be making as a country for delivering our energy needs. Yesterday at Allington House, London, he number-crunched his way through many detailed scenarios for how the UK could achieve sustainability through a combination of renewable energies, energy efficiency, reducing energy consumption and expanding other sources of energy. The thrust of his approach seems to be to assess realistically what can be achieved, how much people will be prepared to change, and then persuade the government and other implementers to get on and do what’s needed.

What was his conclusion? In a nutshell, “It would be very difficult to live on renewables, at least as we currently live”. He argued strongly that renewables like PV, solar water heating, biomass and wind power would have to be at country-scale to be able to make a significant impact. Wind power, for example would have to include massive offshore and onshore farms covering a large proportion of the country as well as vast underwater ones in the North Sea to make a real difference. Most of his favoured solutions were fairly obvious and widely touted – insulation, turning down thermostats, reading energy meters and using heat pumps (air source and ground source). Others were more contentious - electrifying transport, importing electricity from solar farms the size of Germany in North African deserts, and possibly expanding nuclear power stations. His ideas are likely to polarise audiences into those that see his approach as refreshingly realistic and others who are not happy with any role for nuclear power. Mackay doesn't necessarily advocate a strong role for nuclear, but wants those who reject it to make sure their numbers for energy supply still add up.

MacKay, a physics professor at Cambridge University gave his presentation at the Sainsbury Family Charitable Trusts office in London, where the Ashden Awards is based. Find out more and download the book for free and at www.withouthotair.com