Development of an electro-osmotic heat pump

Abstract

The majority of heat pumps and refrigerators is driven by a mechanical compressor. Although they usually function very well, the search for new and in some cases better heat pumping concepts continues. One of the topics in this field is the development of an electro-osmotic heat pump. As each electricity driven heat pumping technique, electro-osmosis is related to a power generation equivalent: the fuel cell. By applying a direct current voltage over the compression unit a pressure difference can be realised, leading to a heat pumping effect. Since 1995 TNO MEP has been working on this concept. After a quick theoretical scan, it was concluded that the concept might work. This quick scan was followed in 1996 and 1997 by experimental work with the aim to demonstrate the compression function. As it proved to be successful a new test rig is being built in 1998. It will be evaluated in the next months with respect to capacities, Coefficient of Performance and part load behaviour. Besides the influence of input parameters will be determined. Of course the concept has a number of advantages over conventional compression machines. An electro-osmotic heat pump has no moving parts, can be very compact, does not make any noise and uses an environmentally friendly refrigerant. Attractive applications may be small air-conditioners, for example for cars or buses, heat pumps for combined heating and cooling and specialities for small cooling capacities