The Bunsen Air System is a very low energy hot water heating system. It uses only 400 watts of electricity to run a small pump and a compressor and only when heating the water. It is extremely cheap to run as it takes advantage of ThermoDynamic effect and therefore all the heat energy from the atmosphere is free! This technology is not dependent on direct sunlight, unlike most types of solar hot water heating systems. Instead energy is transferred from even the coldest weather and it works day and night – the perfect solution for the U.K. climate.