Cogeneration

What is cogeneration?

Cogeneration is production of two useful forms of energy such as high-temperature heat and electricity from the same process. For example, while boiling water to generate electricity, the leftover steam can be sold for industrial processes or space heating.

Cogeneration is a high-efficiency energy system that produces either electricity (or mechanical power) and valuable heat from a single fuel source. For example, a hospital cogeneration plant could produce some of the power and all the hot water needed for its laundry and hot water system from the waste heat it generates. Similarly, office buildings can produce power for electricity and air conditioning from the waste heat generated by its air conditioning engines.

Cogeneration is sometimes known as "combined heat and power", or CHP. It offers major economic and environmental benefits because it turns otherwise wasted heat into a useful energy source. This greater efficiency means carbon dioxide emissions are cut by up to two thirds when compared with conventional coal-fired power stations.

Businesses, Government agencies and facilities most likely to benefit from cogeneration are those that use large quantities of hot water, heat, steam or chilling such as hospitals, large maintenance facilities, aquatic centres and laundries. Others to benefit from cogeneration include hotels, office buildings, food and beverage processors, chemicals and plastics producers, pulp, paper and fibreboard manufacturers, metals processors, textile producers, shopping centres, universities and TAFEs.

Cogeneration is a proven and reliable technology currently operating at over 100 sites across Australia.

What are the benefits of cogeneration?

Cogeneration can significantly reduce energy costs and greenhouse gas emissions, typically by up to two thirds. Local air quality benefits can also be achieved through the replacement of older coal-fired boilers. In addition to reducing operating costs, cogeneration also increases resource utilisation.

What is the potential for cogeneration in NSW?

DEUS research indicates that the potential for small-scale, gas-fired cogeneration in NSW is well over 200 megawatts (MW). There is also significant potential for cogeneration plants fired by other fuels, including biomass (for example, plant waste from sugar or cotton harvesting), or biogas (for example, methane produced by sewage works or piggeries). Some 200 MW of gas-fired cogeneration alone could reduce the State's energy bill by $50 million per year and reduce greenhouse gas emissions by 800,000 tonnes per year.

Cogeneration Links

Here is a collection of sites for organisations interested in cogeneration:

Business Council for Sustainable Energy (BCSE)
The Australian Business Council for Sustainable Energy (BCSE) represents the interests of the renewable energy, cogeneration, gas-fired generation, waste-to-energy and energy efficiency industry. To assist potential cogeneration hosts, BCSE has developed the Cogeneration Ready Reckoner and user guide to assist in the technical and financial analysis of cogeneration.

Energy Networks Association
This site is hosted by the Energy Networks Association, which is the peak national body representing gas and electricity distribution businesses throughout Australia.

COGEN Europe
A large and comprehensive organisation promoting cogeneration in Europe.

UK Combined Heat and Power Association
The association supporting the rapidly increasing use of combined heat and power in the UK

Building Energy Solutions Centre (American Gas Cooling Centre)
A site providing information on highly efficient and environmentally friendly heating and cooling solutions and power systems for 21st century buildings.

US Combined Heat and Power Association (USCHPA)
An association that aims to create an environment in which combined heat and power is fostered as a major energy source in the United States.

UK Combined Heat and Power Club
A place where combined heat and power users can get together to exchange ideas and experiences.

University of Rochester District Energy Library
A great source of information on many kinds of energy, but particularly cogeneration.

International Cogeneration Alliance
An industry federation working to promote sustainable economic development and energy modernisation through the use of cogeneration. 

Cogeneration Case Studies and Project Summaries

Macquarie University

Two 760-kilowatt, gas-fired generators have been installed to provide electricity for general use at Macquarie University. The waste heat powers an absorption chiller for air conditioning, with chilled water storage to level out peak air conditioning loads, and supplies heat for University use. This is the first system in Australia to use combined power, heat and cooling with chilled water storage. The $6.7 million project is saving 5,400 tonnes of carbon dioxide per year and will save the University an incredible $20 million in energy costs over 23 years. Download the case study

Broadwater Sugar Mill

The Broadwater Sugar Mill runs a cogeneration system based on combustion of sugar waste or "bagasse". By upgrading a transmission line, the mill is now able to export a further 5 megawatts of electricity to the grid. The upgrade saves 22,000 tonnes of carbon dioxide per year.

Newcastle University Microturbine

The University of Newcastle has successfully implemented Australia’s first commercial application of a gas-powered microturbine to help realise both financial and environmental benefits. The 30kW natural gas-powered microturbine is at the heart of the University’s Medical Sciences building cogeneration unit. The plant provides some of the power for the Medical Sciences building air-conditioning system, while the wasted heat is captured and turned into hot water to feed the domestic hot water system as well as to provide heating for the air-conditioning system. Download the case study

Other Cogeneration Project Case Studies:

Griffith Hospital Looks to Cogeneration

Cogeneration Facility a Win-Win for Coopers Brewery & AGL

Crown Hotel-Casino Benefits from Hidden Power

Rockdale Beef Wins With Cogeneration

UNSW Delivers a Cogeneration First