Properly understanding your energy load at the start will save countless headaches later on in your CHP project.
What is an energy load profile?
An energy load profile provides a breakdown of the energy consumption patterns of a building, this should be used to correctly size a CHP system. Unlike conventional power and heating systems, CHP is not focused on maximum requirement during peaks in demand.
It’s best to gather load profile data on an hourly or half-hourly basis, rather than trying to take a weekly average.
Heat from CHP is most effectively absorbed in systems with an operating temperature of 90ºC or below, and with a near constant demand through the year.
Profiling the energy load involves measuring the heat demand against the power demand and understanding the ratio. CHP is best in buildings or processes where heat to power is around 2:1.
A building’s cooling efficiency can be improved by using the CHP’s heat for cooling, rather than heating. This involves installing an absorption chiller, effectively turning it into a combined heat, cooling and power system (known as trigeneration). This will also adjust the energy load profile.
Changing your load profile
It is difficult, but not impossible, to adjust an energy load profile via measures such as:
- Installing energy management controls.
- Improving insulation.
- Efficient lighting schemes, with occupancy sensors.
- Adjusting energy load in accordance with building occupancy.
- Connecting buildings, or using thermal stores to keep heat.
- Changing the plant’s operating hours.
Consider other no-to-low cost energy efficiency options to adjust the energy load profile. It is important to take these steps before you size your plant, to avoid installing the wrong size, making it difficult to implement such measures afterwards.