Växthus på Vaksala Eke

This project has been carried out on the behalf of IHUS and the aim was to find a solution to a greenhouse with an associated cafe on Vaksala Eke just north of Uppsala. This complex is intended to be self-sufficient on heat, electric power and crops. In the project we have created a greenhouse that fully supplies the cafe with crops during the summer, while during the winter the greenhouse only provides 8-16% of the cafe’s demand of crops. Six different scenarios were created to cover the heat demand of the greenhouse and the cafe. The following scenarios for the heat supply were considered: ground heat; solar thermal energy and ground heat; geothermal energy; solar thermal energy and geothermal energy; bioenergy; solar thermal energy and bioenergy. These six scenarios were compared to one another to obtain the most profitable system. The results showed that the scenario with the shortest payback period for heat generation, is the ground heat scenario. Photovoltaic solar panels is the only source of electric power examined for the small-scale operation on Vaksala Eke. All the scenarios, except for the scenarios with bioenergy, were fully self-sufficient on heat, on the other hand all the scenarios were self-sufficient on electricity over a year.