CHP in a Box: Advanced Combined Heat and Power Package Systems

Combined heat and power (CHP), or cogeneration systems have a widely proven capacity to save energy, money and environmental emissions while simultaneously increasing facility reliability and resilience.

CHP is the simultaneous production and recovery of two or more useful forms of energy from a single fuel consuming device. This advanced and highly-efficient approach to generating electric power and useful thermal energy involves recovering up to 80% of otherwise-wasted thermal energy and putting it to use for heating, cooling, process thermal energy, or electricity.

CHP can significantly reduce the annual facility costs for a facility. Most, or even all, of the heat and electricity required by a facility can be generated for less money by a small on-site power plant operating at a higher combined efficiency than by purchasing electricity from one utility and purchasing fuel for heating/mechanical equipment.

The CHP market, which traditionally has been focused on large, bespoke, systems is moving towards smaller CHP applications (some not bigger than appliances) as technological advances are creating new products at various price points. 

According to the 2016 US DOE CHP deployment program, total U.S. CHP technical potential has been estimated in over 240 GW for over 290,000 sites. The technical potential for CHP is concentrated in states with large population centers, leading to a large amount of residential and commercial facilities combined with some industrial applications. The average size of a new CHP system in the US is likely to be around 850 kW, with CHP systems under 1,000 kW representing a 90% of the future potential installations. 

Packaged CHP systems are pre-engineered, factory-assembled systems that can be dropped into the existing energy system of a facility as one plug and play unit for onsite generation of electric power, hot water, heating, and cooling packaged in a weather-resistant, sound-attenuating enclosure. This reduces installation time and cost as well as maintenance. Depending on the facility load requirements, multiple package systems (modules) are often preferred over one larger system. 

Packaged CHP units are available in sizes ranging from 25 kilowatts electrical (kWe) to over 1-megawatt electrical (MWe) generating capacity and include a built-in remote monitoring and control system. These systems use well known and robust technologies, such as reciprocating internal combustion engines and micro gas turbines, as well as technologies such as fuel cells. CHP packages are usually designed to provide low voltage power, heat in the range of 160-195 F, and/or even cooling (tri-generation) if required.

When considering packaged CHP units, facility managers should explore a variety of factors and always choose the technology that is the best fit for the facility, staff expertise and budget. As packaged systems are standardized and tend to have a relatively small footprint they can be installed into an existing facility relatively easily and are often a good fit where space is constrained. This smaller system can also make for easier interconnections with existing utilities. For facility managers, if a packaged CHP system works in one facility, there is the potential for replicability at other facilities with similar load requirements, which can equate to uniform operations management and maintenance programs. This uniformity among sites as well as standardization within the package units allows for ease of operation, management and maintenance of the units. Finally, many commercial, institutional and multifamily facilities have electrical load profiles match packaged system outputs that match packaged CHP systems

 As technology continues to improve, CHP systems will continue to reduce in size and add more functionality. For FMs looking to meet sustainability, resilience and emissions requirements, CHP technologies may be a viable option. 

Some of the advantages of using packaged CHP instead of a custom system are:

• Plug and play systems: complete standard packages ready to be operated ;
• Interconnect process with existing utilities is easier for smaller sytems;
• Fewer skills to be operated are required  on site;
• More standardized maintenance is demanded; and 
• Involve simple contracting arrangements.

It is important that real estate and facility management leaders acquire a deeper understanding of technology and obtain the ability to deploy constantly evolving technologies. The DOE CHP TAPs are committed to supporting IFMA members with relevant information and technical assistance at no cost.

For more information, please contact: 

• Dean Stanberry <mailto:dean.stanberry@abraxasfm.com>, CFM, LEED AP O+M, ESUS Chair
• Gavin Dillingham,<mailto:gdillingham@harcresearch.com> PhD DOE Upper-West and Southcentral CHP TAP Director