Renewable energy and combined heat and power (CHP)

Find out about renewable energy technologies and download guidance on renewable energy generation, combined heat and power (CHP), and ground- and air-source heat pumps.

Renewable energy refers to energy that occurs naturally and repeatedly in the environment. Therefore, it does not release any net greenhouse gases into the atmosphere. In the UK, in 2013 14.9% of electricity was produced from renewable sources (source:

Using renewable energy sources can offer a wide range of benefits to your business:

  • lower energy bills
  • energy price stability
  • security of energy
  • 'green' credentials
  • possibility of selling electricity back to the grid at a premium

Renewable electricity generation

Wind power (small scale wind energy)
Wind turbines are used to produce electricity. They are attached to outside of buildings - require a structural survey and planning permission.

Solar electricity (photovoltaics)
Solar photo voltaic (solar PV) panels or cells convert sunlight into electricity.  They are attached to outside of buildings - require a structural survey and may require planning permission.

Small-scale hydro-electric power
An immersed turbine uses flowing water to produce electricity. This technology is highly site-specific. It requires a near body of water that is flowing and has a drop in level that can be exploited.


Renewable heat generation

Solar water heating (solar thermal)
Uses energy from the sun to heats water up to 55-65ºC. Systems should be roof-mounted and ideally integrated into your current immersion-heated, hot-water system.

Generating power by burning organic material, such as wood, straw, dedicated energy crops, sewage sludge and animal litter. Lots of space is required for the boiler and storage of fuel.  Site access is also important for deliveries of fuel.

Anaerobic Digestion (AD)*
Bacteria break down organic material in the absence of oxygen, producing a combustible methane-rich biogas.  Requires access to large amounts of high-strength liquid organic wastes. Planning permissions will be required and you should consult a specialist about odour control.

*Note: output can be for heating, combined heat and power (CHP) or fuel for transport.

Ground-source heat pumps (GSHPs)**
Using naturally-occurring underground low-level heat.  Most suitable for 'new builds' with appropriate geological features.

Air-source heat pumps (ASHPs)**
Converting low-level heat, occurring naturally in the air, into high-grade heat.  System must be attached to outside of buildings - planning permission may be required

**Note: Ground- and Air- source heat pumps are not completely 'renewable' as they require electricity to drive their pumps or compressors.

Combined heat and power (CHP)

Combined Heat and Power (CHP) is the on-site generation of electricity and the use of the heat that is produced as a by-product.

Renewables and CHP guidance

Publication date: 2010 / 2011 - Information in these guides was correct at the time of publication

The following publications are available for free download:


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