Gavin Gilchrist is the project manager for Inner West Community Energy in Sydney, a group that has facilitated over 400 residential solar PV systems, 40 batteries, and over 30 heat pump hot water systems. Gavin is a former energy efficiency consultant to businesses and governments, and was a partner in the Adelaide and Blacktown Solar Cities. His book, "The Big Switch - Clean Energy for the Twenty-first Century", was published in 1994.