The other day I’ve been to David MacKay’s talk “Sustainable energy — without the hot air”. MacKay got a PhD in Computational and Neural Systems at Caltech and went on to became a leading researcher in estimation and machine learning. Later he became interested in sustainable energy; now he is Chief Scientific Advisor of
Her Majesty’s Department of Energy and Climate Change.

His approach is to explain the problem of sustainability in terms of quantities to which every person can relate. This makes the discussion more meaningful and pragmatic. It works! Even if I’m not that good at remembering numbers, today I still remember that the average European consumes 125 KWh/day, the average American about twice than that. If I fly once internationally every year, that averages to about 25 KWh/day. The same can be done for energy sources: the output of each technology is measured in energy per square meters. For example, we learned that to supply the UK’s energy consumption with solar energy one would have to cover a huge part of the territory with solar panels.

The bottom line is that the only technologies that are sustainable, that is, they will produce energy for the next 1000 years with limited pollution, are nuclear energy, clean coal, and solar power “in other people’s deserts”. All other renewable sources just do not produce enough energy. His views are collected in a book that is available online.

It’s refreshing to see that one can start in a narrow field such as machine learning and go on to make some policy contribution for one of the main problems of mankind.