Horticultural companies with a greenhouse usually use combined heat and power (CHP), also known as cogeneration. CHP is widely used to efficiently generate electricity and heat for production in greenhouses. One of the most frequently asked questions we get from horticultural companies is; 'I generate energy for others with my CHP, so that is deducted from my footprint, right?' The answer to this question often leads to confusion. Therefore, we are happy to explain it with the help of our visualization.
The footprint of the gas used is allocated to the produced product based on its efficiency. We give an example, which can also be seen in the visualization above: an amount of gas that is used in the CHP causes 100 kg of CO2 emissions. The electrical efficiency is 40% and heat efficiency 50%. There is a loss of 10%. Then 4/9 of 100 kg CO2 equivalents is allocated to electricity and 5/9 to heat.
The footprint of a product
The heat and electricity sold from the CHP are not included in the product footprint. This is already deducted from the gas consumption. Supply to the grid or neighbours, therefore, does not reduce the footprint of a product.