Paprikateelt in de hooggeïsoleerde VenLow Energy kas

In order to realise a horticultural sector that operates without the combustion of fossil fuel, the first step is to reduce the demand for heating by improving the insultation of greenhouses. This holds especially for crops that are grown at high temperatures, like sweet pepper. The Venlow Energy greenhouse with its double glass cladding and energy screen is a good example of such a highly insulated greenhouse. This report presents the results of a one year cultivation and serves as a bench mark for the state of the art in energy conserving production of Sweet Pepper in the Netherlands. It shows the greenhouse climate conditions required, and the possibilities to meet these requirements with a low energy consumption and options to realise this from sustainable sources. The application of sustainable energy sources was not tested in practice, but since the exact resources (heat and CO2) required from hour to hour were measured, it is easy to do the math on the amounts and capacities needed. The application of pure CO2 or CO2 from another sustainable source is essential when aiming at a fossil energy free horticulture. Without external CO2 the production will drop substantially, especially because an energy conserving greenhouse has typically a strongly reduced air exchange. But, for the same reason, the amount of CO2 needed to increase the CO2 concentration is quite limited, 25 kg/m² per year in this experiment. With a production of 32.5 kg class I of red Sweet Pepper per m², the experiment has shown that halving the energy consumption compared to the general practice did’nt reduced the production.