A New Zealand engineer is developing a milk cooling system that’s driven by methane power. The design features a bio digester fueled by manure. The energy from the digester, in turn, fuels a heat engine that runs a generator. In addition to producing hot water, the generator would supply electricity for a small-scale refrigeration plant that builds up a store of ice to cool milk safely before it’s transferred to a processing plant.

System engineer Ian Bywater theorizes that the system would be able to supply most of a dairy’s energy demands, making it possible to operate independently of electrical service. However, this concept remains to be tested. The next step will be to test the technology on-farm.