Refrigerators and air conditioning units feature high on the wish lists of people in hot countries. The International Energy Agency (IEA) calculates that by the year 2030 the energy consumption for air conditioning in developing countries and emerging nations will be four times what it is today. It is often the case that the gases used as refrigerants are produced chemically. They are damaging to the ozone layer and accelerate climate change. By contrast green technologies use natural gases in the cooling process, are more energy efficient and can be driven by sun or wind power.