Different primary energy saving techniques for greenhouses have been tested in the past. Those systems were designed by using the first law. However, no attention was paid to the exergy destruction in the processes (second law). This exergy destruction is related to the driving potential of the processes and the mass/energy transfer quantity, and it determines the efficiency of the system. In this paper, different energy saving techniques for greenhouses are studied based on exergy analyses at the process level. Many of the studied techniques could be labelled as "less promising". Based on this assessment, our research team select an efficient dehumidification device (vapour heat pump) and EB (Energy Balancing)-screens as most promising. A greenhouse equipped with those techniques is named "EXE-kas" (Exergy Efficient greenhouse). The prospected dehumidification efficiency of an optimal designed vapour heat pump is around 10. The use of the EB-screens results in a near neutral energy balance of the greenhouse without heating.
- Primary energy saving
- Vapour heat pump