Combined heat and power (CHP) systems are low carbon alternatives to those that incorporate gas or oil boilers in their setup. They capture the water’s heat that is produced during the electric generation process. The estimated average CO2 emissions for electricity generated from a mixture of gas, coal, oil and nuclear power stations is around 430g of CO2 per kWh delivered electricity produced at an overall efficiency of around 40% (i.e. 60% is lost during generation or transmission). In comparison, effectively utilising this wasted heat, CHP systems have been shown to reduce these emissions by approximately 50%.

Choosing to have a CHP system installed in your home or non-domestic property is a practical way of taking control of your carbon footprint. And there are several different terms you’re likely to hear during your research, including:

  • Micro-CHP.
  • Primer mover CHP.
  • Packaging CHP.
  • Bespoke CHP systems.

What is a Micro-CHP?

Micro-CHP is a term that refers to the technology involved in creating these low carbon systems. It is likely the term you’ll hear the most during your research. Micro-CHP boilers generally use mains gas or LPG, meaning they cannot be considered carbon neutral. However, the way that they generate and re-use previously wasted heat to create both heating for a space and electricity allows them to stand as an efficient, environmentally-friendly alternative.

There are 3 main types of micro-CHP technology to choose from – Internal combustion engine CHP, Fuel cell CHP technology and Stirling engine. These are also known as the primer movers within the system (see further explanation of this term later).

Internal Combustion Engine CHP

The most widely used form of this technology, Internal Combustion Engine CHP, uses traditional diesel engines that are reconfigured to run on LPG or heating oils and feature an electric generator. This is the most popular choice for commercial and industrial-grade CHP systems due to the increased capacity.


  • High efficiency.
  • Lower fuel consumption.

Common Uses

  • Large corporate businesses – such a hospital.

Fuel Cell CHP

Here, the previously wasted energy is captured at a chemical level instead of waiting for it to be produced after the burning stage. A steam reformer takes the methane found in the gas and chemically transforms it into both carbon dioxide and hydrogen. The waste heat is used to help warm up dedicated spaces while the hydrogen is exposed to oxygen within the cell to produce electricity.


  • Significantly better energy savings.
  • Low carbon emission reductions.
  • Clean, quiet and reliable.

Common Uses

  • Residential.

All three types allow you to work towards current regulations, including Part L UK Building Regulations while giving you autonomy from the mains power supply and exemption from the Climate Change Levy.

Stirling Engine

Stirling engines use a unique technology that converts both gas and solar energy into heat and electricity. They have a sealed cylinder with two parts – one hot and one cold. The gas inside the engine (normally air, helium or hydrogen) moves from the hot to the cold side. When on the hot side, they move an internal piston that is connected to a generator. This creates electricity. The Stirling engine is combined with a boiler for CHP units to help use this technology for the home or commercial property.


  • Quieter than normal combustion engines.

Primer Mover

The primer mover is a component of micro-CHP systems that creates all of the mechanical power, namely the three terms we described above. They are the parts that generate both electricity and heat at the same time – the technologies that we rely on to help our clients achieve lower carbon and better efficiency throughout the year.

Packaging CHP

With their abundance of new technology, CHP systems can become costly investments for any business. They are generally manufactured bespoke, to fit the needs of each client exactly and help improve energy usage in the building.

Packaged CHP systems are swiftly becoming a highly favoured option. They provide a pre-constructed solution that minimises costs and serves the needs of different businesses easily. Within a packaged CHP system, you’ll generally find:

  • A prime mover.
  • An alternator.
  • Heat exchangers.
  • Control panels.

All components are delivered in a single package, leaving either the client or a dedicated party to install them. This reduces labour costs, speeds up installation and allows more businesses to implement them. Corporate businesses are most likely to choose this option over bespoke designs with them also being a popular choice in new builds.

Bespoke CHP Systems

When businesses have the capacity and the budget to accommodate bespoke solutions, made-to-measure CHP units become a possibility. The opportunities here are vast. A client could choose to have a standard unit installed, such as those available here at Energimizer, or implement a larger-scale option with various CHP technologies combined to suit different rooms and requirements.

Is a CHP System Right For Your Business?

There’s no denying the host of benefits that opting for a micro-CHP system can offer your commercial business. But with such an investment required, both financially and during installation, many will wonder whether it is the most viable option for their business.

We recommend micro-CHP systems for businesses and commercial properties if you use heating and electricity for over 4,000 hours a year. For some, these low carbon alternatives will help them make a conscious reduction in greenhouse gases, in line with an overall business promise or commitment. Once up and running, they help you to reduce energy bills by minimising waste and support in achieving the best energy ratings too.

The benefits of micro-CHP systems aren’t dependent on the size of your business. When used appropriately in any corporate setting, there are many reasons why they are swiftly becoming so popular. Here at Energimizer, we have over 20 years of experience in supplying and maintaining CHP systems for domestic and non-domestic properties. For more information and to discover whether this is a viable solution for you, get in contact here today.