Micro-Combined Heat and Power
Combined heat and power (CHP) is the simultaneous generation of electric and thermal energy from a single fuel source such as natural gas. Micro-CHP, or mCHP, are packaged CHP systems 50kWe or less in size. The overall efficiency of a mCHP system can be as high as 80-85%, exceeding the efficiency of power generation, transmission and distribution system of a central power plant (typically 40 to 45% electric efficiency).
In order to derive the maximum benefit from a CHP installation, thermal energy generated by the CHP unit should be fully utilized by the host facility. The best CHP applications are facilities with high annual hours of operation and continuous thermal load. Facilities in which electrical and thermal loads coincide to a large degree are ideal.
Good applications of mCHP systems include:
- Non-hospital health care facilities
- Hotels and dormitories
- Large multi-family residential buildings
- Gyms and health clubs
- Colleges and universities
- Small manufacturing facilities
- Greenhouses/hydroponic farms
These projects do require interconnection approval. The time required to obtain the interconnection approval from the local utility could be significant and should be considered during the planning process for the project. Please note that approval of an incentive payment for CHP shall not constitute approval of a project’s utility interconnection. There is a separate application process for receiving approval to interconnect a CHP system with the local electric utility. Please contact the interconnection department of your distribution company to learn how to apply for interconnection.
Micro-CHP varies in several ways from larger CHP systems. Large CHP systems are typically custom designed to the specification of a particular customer and facility, which results in varying levels of efficiency and operational characteristics. Micro-CHP systems are typically manufactured as packaged units to standard specifications that are the same for each unit of a particular model. That lends itself to a more standardized approach to incentivizing mCHP systems in Massachusetts. Another difference between larger CHPs and mCHPs is that mCHP systems are more expensive on a dollar per kW basis. Therefore, the PAs are offering an incentive of $2,000/kW for systems up to 50kWe.
Electric utilities conduct Distributed Generation Interconnection seminars several times a year. The following link is provided for dates of previous and upcoming seminars and presentations.