"ENERGY SUSTAINABLE GREENHOUSE" PROJECT: REDUCTION OF ENERGY CONSUMPTION AND ENERGY STORAGE IN AQUIFER

In the current context of predicted shortage of fossil energies, fuel prices are rising drastically. Energy costs are the second largest item in the budget (from 25 to 40% of total costs) for French heated greenhouse growers, after labour. Their economic viability is threatened. Moreover, the increasing awareness of environmental preoccupations (greenhouse gas emissions for example) has to be considered. The greenhouse is a solar energy captor which is however not fully exploited as part of the captured energy is expelled outside by ventilation. Besides, the greenhouse has a very low thermal inertia, which gives rise to important thermal losses. The “Energy Sustainable Greenhouse” project therefore aims to:

• reduce thermal losses: a double plastic cover F-Clean^® is tested, double thermal screens on the roof, thermal screens on the walls are installed,
• improve the humidity control with industrial dehumidifiers,
• develop a greenhouse equipped to store and use the excess energy through reversible air conditioning devices (Aquifer Thermal Energy Storage-ATES), the semi-closed greenhouse.

Fifty percent energy savings are expected. The first years of this experiment showed promising results.