In order to ensure optimum crop yields, commercial growers inject extra CO2 into their greenhouses in the daytime. TNO has developed a system that enables growers to capture CO2 in-house from flue gases, which means that they can make significant cost savings and are no longer dependent on external suppliers.
In recent years, TNO has developed techniques for capturing CO2 from flue gases and even from the air. The process is a simple one. Flue gas is pumped into a liquid-filled tower. The CO2 from the gas comes into contact with the liquid, which contains a substance that binds the CO2. The liquid is then pumped into another tower and heated to release the CO2. The pure CO2 that collects at the top of the second tower can be used for a variety of purposes. An in-house CO2 capture system, possibly linked to a greenhouse CHP system, could be an inexpensive and efficient alternative for many commercial greenhouse growers who now have to buy in pure liquid CO2, with the attendant costs, environmental burden of transport and security of supply issues. These systems, which are based on TNO technology, are marketed by Knook Energy Solutions International. Growers who would like to find out more about energy systems and CO2 dosing in and around greenhouses are welcome to contact TNO.