Combined Heat and Power (CHP) systems, also known as cogeneration systems, are used in greenhouse horticulture to maximize energy efficiency and provide both heat and electricity for illumination. A CHP system simultaneously generates electricity and captures the waste heat produced during the electricity generation process. CHP systems can also capture and utilize carbon dioxide (CO2) emissions produced during the combustion process and use this for CO2 fertilization, as long as the flue gasses are cleaned. The Greenhouse Energy Guide assumes that such a cleaning system is available.

The benefits of CHP in greenhouse horticulture are:
- cost Savings: by generating electricity on-site and utilizing waste heat for greenhouse heating, CHP systems can reduce energy costs and reliance on external energy sources.
- Carbon Footprint Reduction: CHP systems can significantly reduce greenhouse gas emissions compared to conventional separate heat and power systems.
- Improved Crop Production: Compared to a boiler a CHP generates more CO2 per consumed fuel unit.