- Case Studies
Combined Heat and Power (CHP) or Cogeneration (Cogen) is a well-established technology that simultaneously generates electricity and heat from a single fuel input.
Using gas engines, CHP can save up to 30% on primary energy costs when compared to the separate purchase of electricity from the electricity grid and gas for use in on-site boilers.
Combined Heat and Power plants achieve efficiencies of 90% due to the high energy utilisation of the fuel input. Further power efficiencies are achieved because the cogenerated electricity and heat is produced and consumed on-site, avoiding the transmission losses of around 7.5% that occur in transporting electricity from remote generators to consumers.
During combustion of the air-fuel mixture, mechanical energy is released and converted into electricity via the alternator.
This is similar to the process used in traditional gas power stations, but unlike unabated centralised conventional power plants, decentralised CHP systems recycle the excess heat that is released as a by-product of power production. Recovered heat can then be used for space heating, hot water, steam, and industrial processes.
Should there be a requirement for cooling, Trigeneration via an absorption chiller can be connected to the CHP plant so that waste heat can instead be used to produce chilled water for process cooling, refrigeration, and air conditioning.
CHP is a fuel neutral technology and within gas engines can accommodate low-carbon natural gas, renewable fuels such as biogas, biomethane, syngas, sewage gas, and hydrogen as a future fuel.
Hybrid CHP systems that combine low carbon and renewable fuels are also possible. Edina helped implement a hybrid solution at Arla Foods’ state-of-the-art milk processing facility in Aylesbury.
CHP makes a major contribution to the UK energy mix, generating around 7% of total electricity supply, according to the latest government data.
Combined Heat and Power and Trigeneration applications offer a range of benefits for businesses within the industrial, commercial buildings, and public sectors.
Major energy consumers operating in competitive global markets, including manufacturers and companies involved in industries like chemical, oil and gas and paper and publishing can often derive huge benefits from CHP. Collectively, companies in these sectors account for a significant majority of cogeneration capacity in the UK.
Sites with a high and consistent heat/cooling and electricity load profile can maximise CHP savings due to high efficiency. However, the strong economics of gas-fired CHP engines means that many sites with a smaller demand profile and lower heat demand are also suitable.
CHP systems can be installed in both existing and newly built facilities. Cost and efficiency advantages are usually greater when a cogeneration or trigeneration solution is planned in the earlier stages of a project.
The best time to plan a CHP system is usually when:
To maximise the efficiency and cost and carbon savings, it is critical that a gas engine cogen plant is correctly sized and installed. Incorrect sizing is the number one cause of sub-optimal CHP performance. Specifiers need to consider many variables – from energy demand profile to site requirements when sizing a CHP unit.
Read Edina’s guide on how to size a CHP unit.
Financial incentives add to the strong financial returns of CHP. Projects that qualify as ‘Good Quality CHP’ under the Combined Heat and Power Quality Assurance (CHPQA) scheme are eligible for Climate Change Levy (CCL) exemption and reduced business rates.
Read our guide to CHPQA assurance and CCL exemption.
By flexing CHP generated power, businesses can draw on grid power when it is cheapest and to use their self-generated power at peak times. This means that they can avoid peak-time cost, such as Triad periods, when prices are vastly inflated.
Gas power generation systems can also be combined with battery storage as part of a hybrid solution to optimise flexibility and generate revenue from Demand Side Response markets.
Edina can provide flexible CHP finance options to suit your requirements, including low cost power purchase contracts and energy service agreements. This could mean zero capital investment with instantaneous energy savings, thus freeing up CAPEX for alternative strategic investments.
Effective servicing and maintenance are essential to ensure high availability, efficiency, and performance of the CHP engine, helping to maximise operational run time, costs, and carbon benefits.
Edina’s UK and Ireland asset-care teams provide round-the-clock gas engine care – backed by 24/7 remote monitoring, the availability of genuine spare parts and MWM technically trained Edina field service engineers to ensure continuous operation of your CHP plant.
Edina is a leading turnkey/EPC solutions provider for Combined Heat and Power provision with almost 1GWe of contracted capacity across industry. We are the official UK and Ireland distributor for innovative and high efficiency MWM gas engines and provide unrivalled product and customer support of the power solution from a single point of contact.