Providing cheap energy amid a tough economic climate has helped to keep UK’s CHP market afloat. The schemes described here all show best practice – they were all winners or commended within the UK CHP Association’s annual awards, reports Steve Hodgson.
There is nothing like the awarding of best practice status to a set of projects to demonstrate the health and diversity of the CHP and district energy sector in any country, particularly when the projects are rigorously assessed and judged. The UK CHP Association (CHPA) runs an awards scheme each year, and says the winning projects for 2012 demonstrate that investment in efficient green energy makes sound business sense as the UK (perhaps) begins to pull out of recession.
CHPA Director Graham Meeks praises ‘the extent to which the industry has responded to the present economic difficulties, making investment in CHP systems increasingly affordable and making their operation increasingly flexible.’ Meeks adds that the other trend revealed by the CHPA Awards was the growing proportion of schemes that combine the efficiency of CHP with the carbon benefits of renewable resources. The tendency towards renewables is not new, and renewable fuels were a key factor in two of the winning schemes this year.
The CHPA Awards – now in its fifth year – were presented in November at a dinner in London. The nominated schemes covered a range of businesses including pharmaceuticals, hospitals, universities and farms, and are together delivering energy costs savings of over £5 million (US$8 million) per year, says the CHPA, and reducing carbon emissions by more than 130,000 tonnes annually.
Awards were presented in four project categories: Industrial and Commercial; Public Sector; Innovation; and Campus and Community and Residential, as well as an individual Champion award.
Public Sector: NHS Grampian and Centrax
The public sector has been a fertile area for CHP developers in the UK for many years, particularly the health sector, with its high energy-using building estate and lengthy operating hours. The 2012 winning project was a new £12 million CHP energy centre installed at the Foresterhill Health Campus, Aberdeen in Scotland, for NHS Grampian by Centrax.
The new energy centre integrates a gas turbine CHP plant with a steam biomass boiler fired by locally sourced woodchips, and three further dual fuel steam boilers, to provide heat and around 90% of the electricity requirement of the site. The very heart of the new energy centre is a Centrax 501-KB7 gas turbine package, combined with a waste heat recovery boiler.
The Centrax package produces 5.2 MW of electricity and 12 tonnes of steam per hour, ensuring the constant availability of power essential for the safety-critical services provided across one of Europe’s largest medical teaching hospital campuses. Facilities at the site include Aberdeen Royal Infirmary, Royal Aberdeen Children’s Hospital, Aberdeen Maternity Hospital and the University of Aberdeen Medical School.
The new energy centre replaced a boiler house which had provided steam for heating, ventilation, hot water, cooking, laundry and sterilisation services since the 1970s. The package will reduce maintenance and save NHS Grampian in the region of £1 million per year.
The new Centrax unit is synchronized to the grid, ensuring the site can safely revert to grid power if required. No power is exported to the grid but the health campus gains significant savings by avoiding the cost of purchasing grid power. ‘We estimate a reduction of at least 17% in carbon dioxide emissions, which represents 4500 fewer tonnes being released into the atmosphere each year,’ says Graham Mutch, Head of Maintenance at the Foresterhill health campus.
‘One major benefit of this energy centre is the flexibility it provides,’ adds Mutch. ‘The plant is still in a transitional phase, in terms of adjusting to new load profiles coming on stream as the Foresterhill site develops. For example, a new nine-storey Emergency Care Centre block will bring a significant change to the existing load profile. The university is also developing a major new research facility and this, too, will change the load profile of the Foresterhill Campus. In the middle of summer we typically run the gas turbine at 2.8 MW, which will rise to more than 4 MW next winter. So we achieve a good balance between gaining the maximum efficiency out of current load while being able to meet the requirements of the projected load well into the future, providing about 90% of the site’s power.’
Environmentally, the energy centre also wins praise for its exceptionally low noise output, particularly relevant for a health centre with about 900 hospital beds.
Two further schemes were commended in the public sector category.
Highly commended: Hill Dickinson and Southport and Ormskirk NHS Trust
Commercial law firm Hill Dickinson’s specialist energy team was recognized for its work on the recent energy infrastructure scheme at Southport & Formby District General Hospital. The company was commended for the legal services it provided to the hospital in its procurement of a CHP district heating scheme which distributes power to the hospital and its neighbours, which include local housing and a nearby college. The team at Hill Dickinson advised the trust on negotiations with two shortlisted bidders prior to Dalkia Utilities Services being chosen.
The new energy scheme includes a 1 MW engine-based CHP unit, a 420 kW waste heat steam boiler and a low-pressure hot water distribution system with plate heat exchangers.
Working alongside the Ormskirk Hospital NHS Trust, the firm was also responsible for drafting agreements between the Trust and Dalkia.
Highly commended: Edina and Royal Liverpool Hospital
Meanwhile, power generation specialist Edina UK was commended for its installation of a new energy centre that meets all the Royal Liverpool University Hospital’s power, heating and cooling requirements. Now also operated by Dalkia Utility Services, the centre includes two gas-fired CHP units, each rated at 2.65 MW.
The CHP system uses reciprocating engine technology, instead of the more conventional gas turbine approach, to realise the advantages of the electrical efficiency of the engines, which averages over 40%, says Edina.
The installation has achieved an average availability of 95% since it opened, and is supported by a fully inclusive maintenance contract.
Industrial and commercial: deif uk and Copys Green Farm
Instead of a major industrial site, the winning project in the Industrial and Commercial category was a more modest, farm-based system that solved a tricky gas control problem.
|Exterior view of the new energy centre at Foresterhill|
DEIF UK designs and markets control and instrumentation products to be used within distributed power production schemes. It won the 2012 Industrial and Commercial award category for supplying a ‘Delomatic 4’ gas control system that provides a reliable solution for a previously problematic anaerobic digester (AD) gas-fuelled CHP project, operating on a dairy farm with an associated cheese-making business.
|Inside the new boiler house – biomass steam boiler on the left and gas turbine package on the right|
Close to the Norfolk village of Wighton, Copys Green farm has 100 dairy cows and 500 acres of farmed land, mostly producing maize and fodder beat. It operates one of the few AD systems in England, which uses cattle manure, silage from the dairy farm and whey from the cheese-making enterprise to produce biogas for heat and electricity production. Surplus energy is sold to the grid, while by-product digestate replaces fertiliser, which adds to the business advantage of slashing the cost of disposing of manure, silage and whey.
The farm is self-sufficient in the production of feedstock for the digester and the entire volume of gas produced is used as fuel for the CHP.
The DEIF system also secures 85% electrical export capacity for Copys Green Farm’s AD system, making the biogas project run at a profit. With an uptime of 99%, the system achieves 85% of permissible electrical export capacity, says DEIF. Generated electricity meets all on-site demand, and export to grid of 130 kW earns substantial feed-in tariff income for the farm.
Highly commended: ENER-G and GlaxoSmithKline
GlaxoSmithKline (GSK) and CHP specialist ENER-G were commended in the Industrial and Commercial category for their installation of more than 20 MW of CHP generation capacity across eight GSK sites in the UK and Europe.
Turnkey CHP systems delivering a total 20 MW of cogeneration capacity have been installed at eight sites in the UK and Europe. The first CHP plant, at the Worthing site in West Sussex, became operational in 2009, with the most recent site at Ware, Hertfordshire, becoming operational in September 2011.
The project involved the installation of six 2 MW cogeneration units, five 1150 kW units, one 1600 kW unit and two 1 MW units, which provide electricity, hot water and steam to the production facilities. The systems are powered by natural gas. Cumulatively the sites can produce 120 GWh of electricity each year.
ENER-G’s CHP systems are helping GSK to meet ambitious environmental sustainability goals set by the company to reduce the impact of its operations, including demanding targets for reducing their carbon footprint by 25% and water use by 20% by 2020. But, as well as helping GSK to reduce carbon emissions, the CHP schemes are also allowing the company to make financial savings through operating a more efficient power generation system.
Innovation: ENER-G And Tesco
Innovation comes in many forms and CHPA member ENER-G won the Innovation category for its new ‘Universal’ unit – a smaller footprint packaged CHP system that offers the same energy cost and carbon savings as larger packages, but is faster to install and commission, and offers a reduced environmental impact of manufacture. Initially developed for the supermarket company Tesco, the ‘plug and play’ design criterion helps to provide the flexibility to relocate plant from site to site. Tesco has introduced the Universal CHP system to 27 UK stores so far.
ENER-G responded to a requirement by Tesco to provide a smaller footprint and easier-to-commission CHP system and developed the new product range to preserve the 90% efficiency and low-carbon performance of large containerized CHP systems, but within a weatherproof enclosure that is about 40% smaller, 3.5 tonnes lighter and significantly quieter.
The complete outdoor packages are available in five sizes between 90 kW and 125 kW. CHP is a cornerstone of sustainable energy performance at Tesco’s new stores and rigorous monitoring has demonstrated impressive cost and carbon reduction.
ENER-G Combined Power Managing Director Alan Barlow says: ‘Our in-house team has developed a new solution for sites with space constraints and in densely populated urban areas, where low noise is critical and design sensitivities are paramount. It is proving popular with customers in many sectors, including retail and leisure.’
|The latest of eight CHP installations at GSK facilities in the UK and Europe – at Ware, Hertfordshire|
Highly commended: Fleetsolve
Commended within the Innovation category was Fleetsolve, which manufactures, installs, and operates CHP and chilling units fuelled by a sustainable, liquid bio-fuel that has also been developed and is supplied by the company.
Campus, Community and Residential: ENER-G and Loughborough University
The CHP infrastructure at Loughborough University builds on the three CHP units in the existing energy centre which provides heating, cooling and electricity to the University’s Holywell Park Conference Centre. After the success of the university business park installation, ENER-G was appointed to supply a further CHP system for the main campus, which won the Campus, Community and Residential category.
In 2011, ENER-G supplied a 1.6 MW CHP system for the main university campus, providing heat and electricity to the whole university site. Keeping an eye on costs and time, ENER-G supplied a containerized unit, rather than building an energy centre, with site installation completed in six weeks. The company had previously installed a 1 MW CHP system at the Holywell Park Conference Centre in 2009.
Loughborough University Energy Manager Greg Watts says: ‘Since the first ENER-G system was commissioned in February 2009, it has achieved very good reliability and over 90% availability. During the first year of operation there were £150,000 worth of financial savings and 1800 tonnes of carbon dioxide savings – key to the University’s aims to reduce carbon and environmental impact.’
Champion: Paul Woods, Aecom
Finally, the Association recognizes an outstanding contribution to the development of the CHP and district heating industry each year. The 2012 winner was Paul Woods, who has a long-standing and highly distinguished career in CHP and district heating, stretching back to 1983 when he moved into the field from the nuclear sector.
What sets Paul Woods apart, says the CHPA, is his willingness to employ his expertise and engineering integrity to champion CHP and district heating – not by banging the table but rather through his obvious objectivity, analytical rigour and reasoned argument. He has taken this approach through countless publications and conference papers. Most recently, Paul has been closely involved with others in the industry in building a deeper understanding within government – from ministers downwards – of various facets of CHP and district heating.