Abstract: A distillation system comprising: an evaporator section for holding a source liquid to be distilled and including a first heat exchanger arranged to heat the source liquid; a condenser section for receiving vapor from the evaporator section and condensing it to form a liquid distillate and including a second heat exchanger arranged to cool the vapor; and a heat exchange system comprising the first and second heat exchangers connected by means of a fluid circuit containing a working fluid that circulates between the first and second heat exchangers, the fluid circuit further comprising a compressor for compressing fluid passing from the second heat exchanger to the first heat exchanger, and a throttle valve limiting flow between the first heat exchanger and the second heat exchanger.