There is much to be gained by looking at the best, and the four new CHP schemes described and illustrated here show both technical excellence but also innovation in application and commercial frameworks. Of the four winning schemes, spread through the commercial, industrial, community and public sectors, two combined CHP with district energy systems; two are at least part-fuelled with renewable biofuels and two included cooling to make trigeneration systems. The fourth involved the application of mini-CHP technology to multiple sites in London.
|Aerial view of the proposed MediaCityUK development — as it will look in 2011|
Although we have seen few CHP plants built in recent years to serve large industrial sites (and even here there have been one or two very large exceptions) the market for CHP systems to serve buildings, groups of buildings and smaller industrial sites has remained healthy and, in the last couple of years, has begun to grow again as the UK Government sets targets to cut carbon emissions from buildings.
The CHP Association runs an annual awards scheme for outstanding new installations. The 2009 awards were presented at the CHPA’s gala dinner held at Banqueting House in Whitehall, London, last November. Earlier in the day, at the Association’s annual conference, politicians from the three main UK parties had lined-up to stress the importance of CHP and district heating in helping to secure reductions in carbon dioxide emissions across the public sector and wider economy.
CHP is already playing a significant role in securing both cost and energy savings for the public sector. Symbolically, the current Government plans to link the London headquarters of the Department for Energy and Climate Change (DECC) and the Environment Department to the established Whitehall district heating scheme. And, given that there may well be a change of government to the Conservative party this year in Britain, the position of that party has become important.
Graham Meeks, director of the CHPA, explained, ‘In a world where public services will be increasingly squeezed, CHP and district heating provide the scope to drive down costs by delivering long-term energy-efficiency benefits. The Conservatives’ announcement that they will require the government estate to cut emissions by 10% is focusing attention in the right place.’
Meeks continued, ‘In a world where we have become focused on a target to achieve 15% of our energy from renewable sources by 2020, CHP delivers a credible route to start decarbonizing the remaining 85% of our economy which will still be dependent upon fossil fuels. For those parts of the economy that present particular challenges — industry, existing buildings and homes — CHP will be indispensible.
Information on the winning schemes is based on that supplied by the applicants.
PUBLIC SECTOR AWARD
BAXI-SENERTEC UK AND THE LONDON FIRE BRIGADE
Baxi-SenerTec UK (part of the Baxi Group) won the Public Sector Award for its work installing Dachs mini-CHP units in London Fire Brigade (LFB) stations across the capital.
So far, Baxi-SenerTec has supplied 19 LFB stations with Dachs CHP units as part of a campaign by the LFB to improve the energy efficiency and lower the carbon footprint of the world’s largest fire-fighting force. Between April 2007 and September 2008, in conjunction with BTU Heating, the 19 Dachs mini-CHP SE kits — comprising a CHP unit, a condenser and a buffer vessel — were installed. The high water consumption and the 24/7 operation of fire stations make them ideal sites to install the mini-CHP Dachs unit.
The complete scheme installed at just one Fire Station cost £40,000 ($65,000) and resulted in a 13% reduction in the overall energy consumption, a 20% decrease in the site’s energy costs and a decrease in the site’s overall carbon dioxide emissions of 19%. The Dachs unit is a proven, reliable CHP unit with over 20,000 units installed throughout Europe, mostly in Germany.
The project is being used as a template for further projects in London, with the LFB working to make CHP a standard feature of all new and replacement heating systems across the city. Now, both the West Midlands and the Devon & Somerset Fire Authorities are beginning to install Dachs mini-CHP kits into their own stations, having visited one of the Fire Stations in London.
The LFB programme to refit all its fire stations has already delivered a 17% reduction in carbon emissions in April 2008, surpassing the Mayor of London’s target to cut carbon by 15% by 2010. It is now well on its way to meeting its overall 2015 targets (a 20% cut).
Graham Meeks, Director of the CHPA, explained, ‘This was the most popular of all our award categories, reflecting the high level of activity across the public sector as organisations strive to become more sustainable. Baxi’s winning entry stands as testament to the benefits such energy efficiency projects provide.’
INDUSTRIAL AND COMMERCIAL AWARD
COFELY (GDF SUEZ) AND THE MEDIACITYUK ENERGY SCHEME
Environmental efficiency services company Cofely (GDF SUEZ) has won the Industrial and Commercial Award for a trigeneration district energy scheme which will meet the energy needs of MediaCityUK, the new home in Salford, Greater Manchester, for BBC North.
The installation of the CHP Energy Centre will result in an estimated saving of £560,000 ($919,000) in energy costs when compared to sourcing the required power, heat and cooling from conventional sources. The Centre will also produce 29% less carbon dioxide than if the development had opted to use electricity imported from the grid and standard boilers.
MediaCityUK is a £500 million ($820 million) project being developed on a large waterfront site. Phase one will provide a new home for the BBC North and an education centre for Salford University. It will also offer commercial and retail space, seven studios, hotel and residential accommodation — which will all be shaped around a piazza twice the size of Trafalgar Square.
Cofely was commissioned to design, build and operate the trigeneration scheme. Construction began in summer 2007, the first phase went live in November 2009 and the site will be fully operational by 2011.
Electrical power is produced from natural gas, while the heat generated by the engine is recovered as hot water. This is then circulated around the MediaCityUK complex by a community heating network. Surplus heat is also used to chill water, providing a cooling service to buildings. The CHP system will operate at an overall energy efficiency of 78%.
The total cost of the energy centre was approximately £5 million ($8.2 million), plus a further £2.5 million ($4.1 million) for the heat and cooling distribution mains.
One of the most innovative aspects of the CHP system is the absorption cooling system, which turns a CHP, or cogeneration, system into a trigeneration system that delivers heat, power and cooling energy. Surplus heat produced by the engine, which would normally be wasted, is used to drive an absorption chiller to produce cooling energy for distribution locally. During the winter months, when demand for heating is highest, cold water from the adjacent Manchester Ship Canal can be used to supplement the chiller, allowing more heat to be used for heating homes and businesses.
The trigeneration system and its district heating and cooling application demonstrate what is achievable for new developments. This example should serve as an exemplar to potential schemes.
Graham Meeks explained, ‘With the BBC license fee having to stretch further each year, the last thing the BBC could afford in its new home was large energy bills. The Cofely scheme will ensure bills are kept low for all tenants of MediaCityUK whilst also helping the environment. It is a scheme that sets the benchmark for others to beat and demonstrates that district heating is increasingly playing a key role in delivery of cutting edge urban developments.’
COMMUNITY AND RESIDENTIAL AWARD
E.ON AND THE DALSTON ENERGY SCHEME
E.ON won the Residential Award for the community energy scheme it now operates at Dalston Square, a Barratt Development in East London. Dalston Square comprises over 550 residential units (private and social housing), retail units and a library.
|An artist’s impression of Dalston Square, a residential development in East London, UK|
The community energy network provided by E.ON generates and distributes low carbon and partly renewable heat (supplied in the form of hot water) and power across the site.
|The new Museum of Liverpool relies on a biodiesel-fuelled trigeneration system|
The community heating network is estimated to save residents and businesses up to 23% on their energy bills and reduce carbon dioxide emissions by up to 25%. As the scheme incorporates both private and social housing, the potential reduction on energy bills is expected to help alleviate fuel poverty for some Dalston Square residents.
|The Battersea fire station in London, UK|
At the heart of the scheme sits an energy centre comprising a number of CHP units, along with a biomass boiler and gas-fired boilers. Residential units receive their electricity via the national grid; however the library and retail units will receive electricity generated in the energy centre by the CHP units. The system will operate at an 80% efficiency.
Each home or business is equipped with a heat meter to measure the amount of heat delivered — instead of the amount of gas used. Equipped with ‘smart’ technology, the meters are read remotely, with customers receiving a monthly bill in the usual way. As there is no need for an individual boiler, there are no annual boiler inspections or costly repairs or replacements.
The scheme will be operated and maintained under an energy services (ESCo) agreement for the next 25 years and is part of a ground-breaking partnership between E.ON and Barratt to work progressively towards the 2016 zero carbon targets set by the UK Government.
Residents receive a welcome pack on moving into their property, explaining how their home will receive heating and hot water and highlighting the benefits of being connected to a community heating network. The scheme will also be used as an example site to promote and raise awareness of low carbon CHP and community heating networks to the wider community. The development is part of a wider regeneration project, in conjunction with the London Borough of Hackney.
Graham Meeks commented, ‘This innovative scheme highlights the cost savings and environmental benefits on offer when we choose to integrate energy generation into community scale property developments. Everyone using and living at Dalston Square is now able to share in the benefits of the approach adopted by E.ON and Barratt.’
HILL DICKINSON AND THE MUSEUM OF LIVERPOOL
Commercial law firm Hill Dickinson won the Innovation Award for innovation demonstrated in delivery of a sustainable energy project scheme for the Museum of Liverpool, operated by National Museums Liverpool (NML). Working with Cynergin Consultants, Hill Dickinson advised NML on the outsourcing of the design, installation and operation of new energy facilities for the New Museum of Liverpool, to ENER·G Combined Power.
|One of the CHP units employed by E.ON at the Dalston Square development|
Now, through the installation of a trigeneration (combined cooling, heating and power) system, the museum is able to meet its own energy needs through on-site energy generation in an efficient and environmentally-friendly way that will also save the museum over £500,000 ($797,000) a year. The public private partnership structure meant there was no requirement for any capital outlay by NML, effectively allowing the scheme to pay for itself, over time, through reduced cost of energy in use.
The trigeneration system will operate at an overall efficiency of 78%. More than a quarter of the CHP system’s capacity is provided by biodiesel, a renewable fuel which has a much lower emissions than traditional fossil-based diesel.
The services Hill Dickinson provided for this project involved drafting a complex set of agreements between NML and delivery partner ENER·G, which set out ENER·G’s commitment to design and install its proposed energy solution for the Museum by early 2010. The contract also outlines ENER·G’s obligation to operate and maintain the installation for a term of 17 years.
As the project relates to the provision of new energy facilities for a newly-built museum, identifying a saving in energy consumption or carbon is not possible. However, on-site generation is far more efficient than grid-sourced electricity and supplementary heating boilers and coolers. As a result, NML has been able to secure from ENER-G a financial guarantee of more than £500,000 of annual energy and non-energy savings. The potential carbon savings is also very favourable, owing to the efficiency of CHP technology.
The new museum is in the final stages of construction and is due to open its doors to the public in late 2010..
Graham Meeks concluded, ‘The partnership and innovative approach to financing and contracting involved in the Museum of Liverpool project demonstrates the value CHP can provide for all relevant parties. It serves as a blueprint for thousands of other projects around the country, where smart and simple approaches to structuring agreements are unlocking the financial and environmental benefits of on-site CHP energy generation.’
Steve Hodgson is the editor of COSPP magazine