Brief
Dutch Freesia grower Tesselar requires a year-round heat supply for its flowers’ greenhouse, previously provided by gas boilers and thus weighing heavily on the company’s carbon footprint. G2 Energy recommended solar thermal collectors as a solution, since they do not only produce zero-carbon energy but also have the highest yield per square meter, thus significantly reducing energy costs for Tesselar. In 2019, G2 Energy started building the 9,300m2 plant, at the time the largest solar thermal installation in the Netherlands.
Technology
The solar thermal technology used in this installation are flat plate collectors manufactured by G2 Energy, operating with a drain-back system and water as a heat carrier. The drain-back function protects the plant against frost by leading the system to self-drain during subzero temperatures. The excess heat produced during the summer months is stored underground in a 1,400m³ tank and ready to be used on less sunny days in autumn and winter, ensuring a continuous heat supply throughout the year. All the plant components (solar absorber, flat plate collectors, storage tank) were produced in Dutch factories.
Financial Structure
This project received financial support from the Netherlands’ SDE++ programme. SDE++ pays, over 15 years, a tariff per kWh produced, in an effort to bridge the gap between the market and production price for a certain type of renewable heat source. Maximum tariffs change with each new round of applications, which can be submitted once a year during a specified time frame. Tesselaar will receive a maximum of 7.8 EUR cents/kWh over 15 years for heat generated during an annual 700 operating hours at full capacity.