Combined Heat and Power case studies
Updated 12 August 2021
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These case studies have been selected from CHP schemes registered within the Combined Heat and Power Quality Assurance programme.
University of Liverpool
Overview
Location: Liverpool
Date operational: 2014
CHP installed capacity: 4.0 MWe
Investment cost: £7.3 million
Annual cost saving: £1.5 million
Project objective: Provide heat and power to an expanding campus at the University of Liverpool in a way which would reduce the energy bill and decrease carbon emissions.
The site
The University of Liverpool main campus.
30,000 FTE students and 4,700 members of staff.
Undergoing an expansion as part of a capital development programme.
Heat provided throughout the campus via existing district.
The need
The size of the campus is increasing leading to a higher energy demand.
The university required a solution which reduced their energy bill to offset the expansion of the estate.
University wanted to decrease their carbon emissions.
Implemented solution
The university had an existing 3.4MWe CHP unit in the energy centre.
2 x 2 MWe CHP units were installed in a disused Grade II listed boiler house.
The units feed into an existing district heating network which provides space heating and hot water to the campus.
The benefits
The scheme has projected annual cost savings of £1.5 million per year.
Lifetime savings are expected to be £22.6 million.
4.1 year payback period for the £6.1 million loan taken out.
Carbon emissions savings are 5,730 tonnes CO2 per year.
Peter Birch, Engineering Services Manager:
Our new CHP engines have delivered fantastic financial and carbon savings for the University. Without the support and funding from Salix Finance we would have been unable to implement such a large scale project. We look forward to continuing to work with Salix on future energy efficiency projects in order to achieve the objectives in our Carbon Management Plan.
Bath Riverside
Overview
Location: Bath
Date operational: October 2014
CHP installed capacity: 230 kWe
Investment cost: Unknown
Annual cost saving: Unknown
Project objective: Provide space heating and hot water, in combination with other technologies, to 800 new homes via a district heating network.
The site
44 acre brownfield site in Bath.
Located within a World Heritage Site.
Previously an industrial site but had been derelict since 1989.
Undergoing a major development that will include over 2000 homes, a riverside park, school and restaurants.
The need
New homes in the Bath Western Riverside development require hot water and space heating.
The developer agreed homes would be built to Code for Sustainable Homes (CfSH) level 4, leading to a 31% carbon savings requirement.
Implemented solution
230 kWe natural gas fired CHP plant combined with a 400 kWth biomass boiler and 2 2.3 MW gas boilers designed as a backup for peak loads.
These units charge a 30 m3 thermal store which heats water before it is distributed to homes via a district heating network.
Electricity generated by the CHP unit is sold to the grid.
The new Energy Centre is located in a refurbished Wessex Water building.
The benefits
Reduction in carbon emissions of 55%.
Energy savings for the development compared to business-as-usual case of 2 GWh (38%) per annum.
The CHP unit is responsible for half of the carbon savings required to meet CfSH level 4.
Residents benefit from local, secure low carbon heat and hot water with 24/7 backup.
Debbie Alpin, Managing Director, Crest Nicholson Regeneration:
The opening of the Energy Centre is a significant milestone in the development of Bath Riverside. We have put a lot of careful consideration into how the development can best meet the sustainability targets set, and it is fantastic that we have been able to use one of the existing buildings for the Energy Centre, retaining an important link to the site’s history.
Coventry District Energy Company
Overview
Location: Coventry
Date operational: November 2013
CHP installed capacity: 7.7 MWe
Investment cost: £5.3 million
Project objective: Provide a low carbon and efficient energy source to Coventry City Council and local businesses.
The site
The site is a conventional Energy from Waste facility thermally treating household waste to produce steam for electrical generation or process heating.
Conventional incline grate technology in operation since 1975.
The current CHP scheme provides low-carbon heating to buildings within Coventry City Centre most notably Coventry Cathedral.
The need
To assist Coventry City Council to meet their low-carbon targets.
Provide a cost saving for Coventry City Council against conventional heating.
Reduce capital and revenue costs to maintain and replace current infrastructure
Implemented solution
The CHP, a 600,000-litre thermal store with heat back up and a network of 6.6km of buried pipes to consumers in the city centre operated from a sub-station at the Energy-from-Waste site.
Heat taken as pass-out steam from an intermediate stage of a steam turbine.
Coventry Council House, Coventry City Council Civic Buildings 1, 2, 3 & 4, Herbert Art Gallery & Museum, Coventry Sports & Leisure Centre, Coventry Cathedral.
The benefits
Gives customers a carbon saving of approximately 89% compared with a conventional stand-alone gas-fired system.
No mechanical plant, flues, gas etc. required on site.
Savings compared to alternative cost of heating.
Low carbon heat.
Significantly smaller plant space required compared with conventional boiler house and more flexible in terms of location.
Karl Starkey, Managing Director, CSWDC:
Combined Heat and Power provided by Energy from waste is an efficient, green and cost effective solution to traditional fossil fuel energy sources.
Lister Hospital
Overview
Location: Stevenage
Date Operational: October 2012
CHP installed capacity: 1.4 MWe
Investment cost: £2.7 million
Annual cost saving: £0.65 million
Project objective: Improve the energy centre at Lister hospital through installation of a CHP plant to increase energy efficiency and reduce energy costs.
The site
480-bed district general hospital in Stevenage.
Part of the East and North Herts NHS Trust.
Provides hospital services to people across Hertfordshire and South Bedfordshire.
Underwent £150 million investment programme (including this CHP project).
The need
Hospital patient care is sensitive to the stability of energy supplies.
Site is full of energy intensive facilities.
Energy was provided solely by the National Grid.
Significant electricity costs.
Carbon emissions targets to be met.
Implemented solution
1.4 MWe CHP plant and 3 new boilers delivering heating, hot water and electricity to the hospital.
One of the new boilers is linked to the CHP system as a waste heat/fired boiler.
New waste heat pipework.
Steam calorifiers replaced with new plate heat exchangers.
The benefits
Annual cost savings of £0.65 million.
The Trust’s annual carbon emissions reduced by 20% (4,040 tonnes).
Carbon emissions reduction target was met 3 years early.
Hospital now pays less under the carbon tax.
£1.3 million backlog for heating and hot water system repairs was cleared.
Queen’s University Belfast
Overview
Location: Belfast
Date operational: March 2014
CHP installed capacity: 2.0 MWe
Investment cost: £2.105 million
Annual cost saving: £456,823 million
Project objective: Provide heat and power to 2 sites at Queen’s University Belfast in a way that would reduce energy bills and decrease carbon emissions.
The need
The university is aiming to reduce its carbon emissions by 10,000 tonnes by 2020.
The CHP schemes were installed to help reduce the university’s energy bills.
Implemented solution
1.2MW CHP engine was installed at the Main Site and connected to existing on-site infrastructure.
0.8MW CHP engine was installed at the Ashby Site.
The smaller CHP unit was installed in an existing plant room but had to be built in modular on-site due to space restrictions.
The benefits
The scheme is projected to create annual cost savings of £456,823 with 4.6 years of payback period and carbon emissions are to be reduced by 1,269 tonnes CO2 per year.
Excess heat from the CHP is exported to the neighbouring Botanic Gardens that leads to reduced heating costs.
A viewing gallery was also included to allow students to see the CHP plant in operation to help raise awareness of the application of CHP and its long term environmental benefits.
2 additional engines sized 150kWe and 250kWe will be installed at the Centre for Experimental Medicine and the Elms Village student accommodation site.
John Nugent, Head of Estates Development:
The Combined Heat and Power initiative is central to the University’s Carbon Management Programme and contributes substantially in reducing our emissions. We and neighbouring organisations benefit both environmentally and financially from the scheme.
Volac Renewable Energy Plant
Overview
Location: West Wales
Date operational: March 2016
CHP installed capacity: 2.993MWe
Investment cost: £38 million
Payback period: 10 years
Project objective: Provide heat and power using biomass CHP with the least cost and reliance on fossil fuels in a major supplier of specialist dairy ingredients.
The site
Volac is a modern dairy production facility based in West Wales and uses the latest membrane filtration, evaporation and spray-drying technologies.
Volac’s technologies provide high-performance whey protein isolates for the sports and active nutrition markets, lactose for use in a range of food applications and base powders for young animal milk formulas.
The CHP plant supplies 65% of the site’s energy demand.
The need
To replace fossil fuels with renewable, sustainable energy for the factory processes.
To invest in making the plant sustainable, energy efficient and reduce the site’s carbon footprint.
Implemented solution
The CHP system features 2 wood-fired thermal oil boilers (10MWth capacity each), which supply heat to an Organic Rankine Cycle (ORC) system to generate electricity and heat for use in the production process.
The ORC delivers 2.993MWe of electrical power, 13.4MWth hot water and thermal oil feed for higher temperature requirements.
All of the energy generated is used to drive the dairy factory manufacturing processes.
The benefits
10-year payback period for the £38 million capital expenditure.
Site carbon emissions reduced by 60% compared to 2014 baseline.
Secure on-site power and thermal energy generation using locally sourced fuel.
James Neville, Volac CEO:
Our major investment of £38 million in the plant enables Volac to generate sustainable energy to meet the growing needs of our business at Felinfach. It has enabled us to reduce carbon emissions from our Felinfach operations and reduce the carbon footprint of our products. Through this investment, we have been able to employ an additional 5 staff from the local community.