Cogeneration for the Next Generation™:
Ultra-Clean Combined Heat and Power – A Primer
Cogeneration, also known as Combined Heat and Power (CHP), is the production of two kinds of energy – usually electricity and heat – from a single source of fuel. Cogeneration often replaces the traditional method of supplying multiple forms of energy such as purchasing electricity from the power grid and separately burning natural gas or other fuels in a boiler to produce heat or steam. Integrated Cooling and Heating (ICHM) takes this concept one step further. The useful heat resulting from the CHP application can be used to supply heating and cooling needs. This is sometimes referred to as Tri-Generation; electricity – heating – cooling. The recovered heat, usually from the engine jacket and exhaust, is sent to a pre-packaged ICHM where the heat is introduced to an absorber. The resulting chilled water is sent to process or space cooling circuits. Heat not utilized in the absorber is sent to the heating circuit where it is used for domestic, process or space heating needs as the project may dictate. The ICHM approach pre-packages the necessary equipment along with all process piping, valves, exchangers and controls to maximize the efficiency from the waste heat while reducing the traditional cost of a site designed and erected system. While the traditional method of delivering energy is convenient, it is very inefficient and wastes up to two-thirds of the energy in the original fuel. Utility customers pay for those losses in their electrical rates – and always have.
On-site cogeneration systems not only generate electricity more efficiently than central power stations, they capture and use most of the heat that is normally wasted. The ICHM allows for utilization of the waste heat in the delivery of chilled water as well. Depending on your application, the integration of power, heat, and chilled water production into one on-site cogeneration system can generate savings of up to 35-50% for total energy expenditures. And if you’re a big energy user, these savings can go right to your profits.
A Technology For Now – Again
The principles of cogeneration have long been known and put to use in a wide variety of applications – from Thomas Edison’s first electric generation plant in 1891 to modern processing facilities, to municipal utilities supplying power and district heating. In the past, economies of scale favored large, complex projects or special situations.
Today, advances in ultra-clean natural gas fired reciprocating engine technology, heat exchangers and system controls, make cogeneration both practical and economical for applications in varying size ranges.
One aspect of power production that has influenced these advances is the ever increasing need for cleaner energy. Emissions control strategies that allow natural gas fueled internal combustion engines to be applied for CHP and ICHM applications at levels equal to or less than current large power plant standards have further made Cogeneration more practical, economic, and accessible for a broader range of commercial and industrial applications.
The World Is Moving Toward Cogeneration
- Energy savings – If energy for power, heating or cooling is a big component of your costs, your energy savings will be proportionately large. Savings can lead to a quick payback on CHP systems investments when combined with tax credits, excess energy sales and cogeneration gas discounts offered by some utilities.
- High reliability – Generating power and heat on-site, and using the power grid or a standby power system for backup, will improve reliability and maintain productivity.
- Cleaner air – By reducing your dependence on inefficient centralized power plants, you reduce the amount of air pollution those plants produce. New lean-burn gas engine generators are cleaner that ever before, that means reduced levels of nitrogen oxides, sulfur dioxide, particulates and greenhouse gases such as carbon dioxide.
- Easy installation and expansion – Scalable systems from 200 kW to 5 MW can typically be installed faster than a utility can build a comparable high-voltage substation. And the system can easily be expanded as your facility grows.
- Good for the future – Since cogeneration significantly reduces energy waste, it preserves our coal, oil and nuclear resources for future generation.
The Benefits Of Cogeneration Are Compelling
The US Department of Energy (DOE) has established a goal of doubling the amount of electricity produced by cogeneration – from 9% to 18% – by 2010. The European Commission has established a similar target. Switzerland, a country where cogeneration accounts for 77% of the country’s electricity and Denmark (40%), are already well ahead of the CHP curve. Innovative city leaders such as the Mayor of London, Ken Livingston, are requiring a major commitment in city planning for the inclusion of CHP as a major tool in reducing energy poverty, green house gases, and general fiscal and infrastructure management.
Continuing changes in economics, technology and energy policies are combining to make cogeneration a smart, cost-effective choice throughout the world.
- High electrical rates in many parts of the world and regions of the U.S.
- Major advances in ultra-clean natural gas fired reciprocating engines – the most efficient and proven cogeneration technology – have made cogeneration systems viable for a wider range of applications.
- Commitment by many countries to reduce emissions by transitioning to cleaner and more efficient means of producing energy such as results from CHP and ICHM approaches to packaged generation.
- Generous tax credits, together with emission reductions mandated by the Kyoto Protocol, have stimulated investment in cogeneration systems worldwide.
- The emergence of cogeneration solutions providers such as EliteEnergy Systems. who will partner with businesses and institutions to build, own and operate turnkey CHP systems.
- Industrial / chemical plants
- Commercial facilities
- Government facilities
- Colleges and Universities
- Food processing
- Health clubs
- Swimming pools
- Nursing homes
- District heating and cooling
- Coal mining and oil fields
- Landfills and sewage treatment plants