The ELEC-HP project aims at developing a family of automotive heat pumps to be sustituted to heating by electric resistances. Barriers to overcome are as follows:
- use a refrigerant with a GWP < 150, which presents good energy efficiency in heating for -20 °C outdoor temperature and in cooling for + 40 °C outdoor temperature
- design fully-brazed aluminum heat exchangers, with new fin design, optimised for improved management of frosting/defrosting cycles,
- design new defrosting strategies that do not reverse the cycle and do not impact the cabin comfort,
- develop, for road vehicles, strategies of pre-conditioning including energy storage,
- design systems diffusing heat and coldness as near as possible of passengers in order to improve the ratio useful energy/produced energy,
For electric vehicles, stakes are to reduce of more than 50% the annual energy consumption of thermal comfort and to obtain autonomy savings of more than 50% on cold periods with high occurence (-5°C / +5°C) compared to heating with resistance.
For rail cars, stages are to limit by at least a factor 3 the energy consumption currently ensured by electric resistances and to improve the comfort felt by passengers via improved heat diffusion.
Articulation simulations/innovative design/component tests /system integration
The first innovative path is in the design, simulation, and definition of vortex generators allowing the amplification of heat exchanges and the frost growth management. This management is dual, either by the management of the heat-exchanger rows or by limitation of the solid deposit.
The second innovative path is associated to the systemdesign at several scales: hte heat-exchanger scale for the management of the frost deposit and defrosting, the heat-exchanger scale for the minimisation of exergy losses due to defrosting, the vehicle scale for the minimisation of needs and the energy recovery of the extracted air, the user scale for the supply of the adequate energy quantity.
- low energy impact defrosting strategies
- evaporator-condenser design with low frost deposit (under development)
- system development af a reversible heat pump operating from -20°C to +40°C (in the near future)