Magnetic cooling moves into electric vehicles
A conventional vehicle typically uses the engine waste heat to run the cabin heating and a gas compression cycle for cooling and dehumidification. In electric vehicles, however, there is lack of available heat waste and the climate control system has a significant effect on energy consumption and mileage. Heat pumps supplying cooling and heating capacity are a promising approach for improving energy consumption. Within ICE (Magnetocaloric refrigeration for efficient electric air conditioning), researchers developed an efficient air conditioning and heating system that is based on a magnet-based heat pump. Relying on the magnetocaloric effect, the innovative automotive heat pump is a much more environmentally friendly option from standard gas compression forms of refrigeration. It also outperforms conventional chillers, reaching even double efficiency. Researchers targeted high-efficiency levels through suitable magnetic materials, smart design and micro-channelled heat exchangers. A key task was to design a thermal power distribution system that provides local thermal comfort, while minimising energy demands. An integrated thermal system provides temperature control of all the on-board systems. Using the rejected heat as heat source for the magnetocaloric heat pump and the exceeding cooling power, the system keeps the battery temperature below the critical level. The prototype system was successfully installed on a small electrical bus to test its reliability. With some further technology improvements, magnetocaloric air conditioners could represent a major breakthrough not only in the automotive sector but also in other industries.
Keywords
Magnetic cooling, electric vehicles, refrigeration, heat pumps, magnetocaloric, air conditioning
