In September last year, three of the twelve hectares of Tielemans' greenhouse complex in Boekel were equipped with Philips GreenPower LED toplighting compact in addition to the existing HPS lighting. This increased the light level by almost two and a half times from 100 to 244 µmol/m²/s. Owner René Tielemans is a satisfied grower: "We can now extend the growing season and mimic the amount of light on a clear spring day in the winter. This enables us to supply cucumbers to our customers all year-round."
GrowWise control system
Tielemans Groentekwekerij opted for a hybrid light installation where the existing HPS installation was expanded with Philips LED. LED has a lower heat output which allows for better control of the greenhouse temperature compared to HPS. This will reduce the need for ventilation and therefore the loss of CO2 from the greenhouse. Tielemans: "A greenhouse with only HPS lighting produces too much heat, so we can't add additional conventional lighting. A greenhouse that is too hot, no longer stimulates growth. It produces too much plant and not enough cucumbers." The LED installation is controlled by the GrowWise control system (GWCS): a link to the climate computer allows the light to be dimmed and controlled, and you retain control over the amount of light. "Very important," says Signify plant specialist Stappers. "This provides you with much more flexibility to determine the light level separate from the heat in the greenhouse. You can optimally adjust the light intensity according to the needs of the crop."
Less energy per product, more light, more sales
Tielemans can now light his plants according to the needs of the crop and be more flexible with the costs of electricity consumption. "Less energy goes in and more light comes out," René explains. "Even when electricity prices are high, we can decide for ourselves to temporarily use the grow lights less. That way we also save even more on our energy bills."
Year-round production means that the supply is more spread out within our grower's association. "Winter cultivation doesn't necessarily yield more cucumbers per square meter, but the market supply is more limited, which means the products can be sold at higher prices during the winter months. That higher yield is also needed with the rising labor and energy costs associated with this change in cultivation."
Reliable partner with years of experience
Grow lights for greenhouses are offered by several manufacturers around the world. Still, Tielemans' choice for Signify was not a difficult one. "Signify is reliable, has a good reputation and years of experience. The technology used here is new and therefore I want a partner I can rely on again in case of any problems." Moreover, the cooperation does not stop after the installation. A plant specialist supervises the start-up and advises on the optimal light recipe, so that the grow light promise is fulfilled. "Erik Stappers is a professional. He is committed, knowledgeable, and well-informed. We discuss lighting strategies for greenhouses. Actually, we share the same passion and we both want to improve the cultivation process," says Tielemans. "Also, the cooperation with their regular installation partner Stolze, whom I also know well personally, immediately created mutual trust."
Pioneers pur sang
Pioneering with new innovations is not new to Tielemans Groentekwekerij. LED grow lights are part of the company's commitment to better quality, a good environment and sustainability. "We are progressive and sometimes we go against the grain," says the director. For example, in 2011 our company was the first to supply cucumbers with an environmental label, now known as Planet Proof. This has now become the norm. We were also the first in the southern part of the country to start sealing our own cucumbers."
The plan to grow cucumbers year-round did not come out of the blue. The demand for this comes from Dutch supermarkets who want cucumbers with a stable quality and security of supply from their own region throughout the year. Tielemans took up the challenge with a project group of a number of cucumber growers within Kompany, a fruit and vegetable sales organization in Venlo, the Netherlands, which also provided a significant part of the financing.
Tielemans, for example, sees growing cucumbers under LED lighting as a mutual learning process that still needs to mature. "The experience of the growers is also very important for Signify to make the light recipes even better. We learn a lot from and with each other and that creates a win-win situation.