Colin gave an entertaining short talk on how electric cars work. He described the various energy sources (including electric) available in principle for automotive propulsion and compared them in terms of cost, efficiency, endurance, etc. He gave a comparison between lead-acid & Li-ion battery types. It was pointed out that the basic commercial costs of petrol/diesel and electric propulsion were approximately the same, but that electric propulsion would clearly win out in that respect unless taxation rules were changed. However, there were significant logistical implications for electric cars (availability of charging points, exchanging batteries, use of solar charging, etc.) Perhaps in the short term hybrid vehicles may prove to be a pragmatic interim solution, although currently costly and still lacking in endurance if mainly reliant on electricity.