Cogeneration units and heat recovery

Cogeneration is a technique in which two different forms of energy are produced simultaneously, both electricity and heat, within a single production unit. The heat generated to produce electricity is used in industrial processes and to heat buildings.

This type of installation allows companies and local authorities to optimize energy efficiency and reduce their carbon footprint. When combined with biomass and biogas, the resulting energy is renewable, too. At Idex, cogeneration is widely used across our infrastructure and on our clients’ behalf.

Cogeneration: the ultimate two-in-one solution

The concept behind cogeneration is simple: recovering by-product heat produced by an electric generator. By-product heat refers to thermal energy that is not otherwise recovered or reused. This type of two-in-one installation allows you to generate electricity via natural gas or another fuel, resold over the electrical distribution network. It also allows you to recover the heat generated by the electrical production process to power a building’s thermal facilities, an industrial process, and even a heating network, depending on the power levels of the cogeneration unit.

Cogeneration is therefore reliant on an engine, similar to the kind you’d find in a car. This engine is powered by natural gas. It converts the combustion-generated chemical energy into mechanical energy, which is transformed into electricity by an alternator. The exhaust gas produced by the combustion of natural gas is expulsed from the engine at temperatures of several hundred degrees. This residual heat is recovered using a heat exchanger. It is then recycled locally at a thermal facility in order to heat homes and professional premises, or to produce industrial utilities.

Cogeneration: a virtuous process handled by Idex

Depending on the fuels used to produce the electricity, cogeneration can be considered renewable. Biogas and biomass are renewable fuels that are frequently used in cogeneration, and Idex has been specializing in producing them for several decades now. Cogeneration is an extremely eco-friendly option because of the energy-saving nature of the process.

Simultaneously producing electricity and heat using the same primary energy source via a single unit has the advantage of significantly optimizing energy efficiency across a region or industry. This means cogeneration results in lower CO2 emissions.

Conversely, generating the same amount of energy with two separate installations, a boiler and a combined-cycle power plant, requires an extra 40% of primary energy on average, compared to a cogeneration unit. Over and above the environmental aspect, the energy savings generated by cogeneration units have a nonnegligible impact on the user or company’s bills.

Idex and cogeneration

Idex chooses to work with European specialists in cogeneration. Go4Green is a Belgian company that installs and manages over 90 cogeneration projects in the Brussels area, and Idex Baltic runs a cogeneration unit that powers the heating network in Kaunas, Lithuania’s second biggest city.

In 2018, Idex acquired Taranis Energy, a French company specializing in designing, building, and financing biomass, biogas, cogeneration, and steam electricity and heating power plants. It also runs a cogeneration unit on behalf of a paper manufacturer.

Your company could reap the benefits of heat generated by a local incineration plant to run your production facilities via steam power. Thanks to their inside-out knowledge of regional institutions and the industry sector, Idex’s teams serve as the perfect partners in assisting you in your energy transition.

European partnerships and a host of success stories across France combine to make Idex a leading name in the green transition movement. We are now a recognized partner in installing, running, and maintaining cogeneration units across France and Europe.

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Cogeneration in France and further afield

In late 2019, Idex opened a cogeneration plant at the Centre Hospitalier Spécialisé (CHS) site in Fains-Veel (55, France). This two-in-one solution has been designed, developed and managed by our group.

  • Financed by Idex, the plant is set to produce electricity that is then resold directly over the electricity network via a CR16 cogeneration contract
  • The cogenerated heat will be transferred to Idex and used to heat the CHS hospital centre over the contract’s 15-year period.