Current greenhouse operations are very energy intensive, requiring supplemental heat and, in facilities with grow lights, large amounts of electricity. Cogeneration can be used to supply electricity and heat with significant energy cost savings. CHP units also supply another important by-product, carbon dioxide. Fossil fuel dependency can be dramatically reduced and even removed in greenhouses by leveraging passive solar, thermal mass and cogeneration.
The impacts of CHP for greenhouses can be significant:
The steep rise of natural gas prices in 2008 (up to $14.47/GJ) stressed Alberta greenhouse operations to the point where subsidized gas prices from the Alberta Government were required to prevent many operations from growing bankrupt.
Two large commercial greenhouses in Alberta (Country Fresh in Medicine Hat and Doef’s in Sylvan Lake) have proven they could increase their revenues about 2 times by effectively using artificial lights. Most use high electricity consuming light varieties (HPS). LED lights represent a significantly lower energy requirement, but even without LED installations, CHP will reduce electricity costs, increasing margin.
Many commercial greenhouse operators buy CO² or burn natural gas in boilers year round just for the benefit CO² provides (e.g. Doef’s uses 18 GJ’s per hour in the summer on 11 acres for CO²).
Cogeneration has been used for decades in Holland and elsewhere. Nexus Power Solutions brings unique skills and knowledge to meet greenhouse needs.