CHP in a greenhouse is a superb way of making maximum use of natural gas, as CHP produces:
1. Heat, recovered from the engine to warm up the greenhouse.
2. CO2 from the exhaust gas, used to improve and accelerate the
growth of plants.
3. Electricity to maintain an installation.
Thus a catalyst system must be installed to convert these gases to clean and harmless ones. Greenhouse owner can decide to install a Selective Catalytic Reduction (SCR) followed with an oxidation catalyst system to increase the CO2 levels in the exhausts while cleaning harmful gases. As an exmaple, the 2 MW gas engine will produce 240 kg/h/ha of CO2 which is enough CO2 to cover the needs for the greenhouse surface of 4 hectares.
In regards to the heating of the greenhouse, the recovered hot water can be stored in special insulated buffer tanks and distributed through metallic tubes throoughout the greenhouse. The needed temperature of the greenhouse is usually kept constant.
Moreover, the excess of electric energy, after a necessary amount is consumed by greenhouse, can be supplied to the local utility.
Cogeneration system for greenhouse is made of different elements. The whole is controlled with a sophisticated controller that not only manages the electrical output of the generator set but also manages the heat and CO2 concentration process.