Richard Lafferty discovers that residential developments are wising up to an old and yet newly fashionable technology, chp.
Cogeneration and Total Energy might, to the misinformed, sound remarkably like a pair of 1970s disco combos. In fact, they are two of the trendier terms used to describe combined heat and power, or chp.

Although superannuated forms of this technology have been widely used in Russia and other parts of Eastern Europe for decades, the Western world has, until relatively recently, turned its smartly snubbed nose up at chp.

This is shameful when one considers that chp typically achieves a 35% reduction in primary energy use compared with power stations and heat-only boilers.

However, the value of chp has not gone unnoticed by the electrical and mechanical services industry. Powerminster, the m&e services subsidiary of the MJ Gleeson Group specialises in community heating, whereby centralised boilerplant is connected to domestic and commercial properties by a network of heating mains to provide space heating and hot water.

It is a widely held view that when Government finally realises that environmental policies are not only right but also potential vote-winners, chp will enjoy a meteoric rise. For m&e contractors, it is set to be a growth area, which they can only ignore at their peril.

Quite apart from the obvious green credentials of chp, it’s worth remembering the economic benefits. It allows host organisations to make big savings, when there is a suitable balance between the heat and power loads.

The current mix of chp installations achieves a reduction of over 30% in CO2 emissions in comparison with generation from coal-fired power stations, and over 10% in comparison with gas fired combined cycle gas turbines.

The latest figures from the Combined Heat and Power Association (CHPA) are very encouraging. Over the last decade capacity has more than doubled, representing an average growth rate over the period of 7% per annum.

Moreover, a growth rate of 9% was achieved in 1999 with a net increase in capacity of 354 MWe (this breaks down as 414 MWe of new capacity added while 60 MWe was retired) – a significant improvement compared to recent years.

One of the misconceptions about chp is that it exists only in huge buildings. The CHPA is promoting the idea of small-scale chp for homes. Tenants’ energy bills, it claims, can be cut by supplying locally-generated, green energy to their homes.

The CHPA says: “More than 20 000 households are getting cheaper energy and playing their part in reducing national carbon dioxide emissions by thousands of tonnes.

“This is because local authorities, housing associations and other organisations have installed some 70 small-scale chp units in the high rise residential sector over the last few years.”

And to give the Government (and Transco) some credit, several grant and support programmes for chp are currently available.

In the residential sector, as well as advice and information, development support is available. This is up to 50% (up to a maximum of £10 000) towards specialist advice or feasibility studies. And capital grants, up to 25% (maximum £150 000, typically £30-£60 000 towards the chp installed costs) are also available, as well as a badging grant of around £5000 to cover monitoring access and publicising, for schemes that go ahead without a grant.

All these schemes are part of the Energy Saving Trust, funded by Transco and the DETR.

Moreover, SoP2/CHPPirb2 is the official name of another capital grant scheme, offering 20-30 % towards the total cost of converting electrically heated multi-residential dwellings to community heating/chp. This is managed by the CHPA and funded by local electricity companies via standards of performance for energy efficiency.

Back to Powerminster. The company has recently concluded a Pathfinder Private Finance Initiative (PFI) partnership with Manchester City Council, using chp in a community heating system.

The PFI scheme has a total value of £11 million and a contract value of £2·5 million for the community heating system. It involves heating 417 council flats in six tower blocks in the Rusholme and Newton Heath areas of Manchester.

A special purpose company, the Manchester Energy Company was set up when contractual agreements were finalised.

Powerminster provided the technical and operational expertise during the design and installation and is responsible for the ongoing operation and maintenance of the system for a period of 20 years.

Powerminster stripped out the existing heating systems and installed new central heating complete with smart card pre-payment technology. The systems are supplied from two new energy centres, one on each site, with a 150 kWe chp engine acting as lead-boiler, supported by additional boilerplant at times of high demand.

Tenants are supplied with heating and hot water at an initial charge of 2·4 pence per KWh, later reduced to 2·27 pence per kWh, which is “well below the peak price of electricity for heating”, says Powerminster.

The start of the 20-year operation and maintenance phase began recently when the installation work was completed.

Powerminster is incentivised to perform to the required standard by a Performance Penalty Mechanism, which allows for reduced payments for poor performance.

If this exceeds the set criteria, the contract can be terminated. The company manages this risk through regular monitoring of key performance indicators and benchmarking. It is the aim to improve upon the standards rather than merely maintain them.

Brian Sexton, chief programme manager of Manchester Housing, who led the Council project development team, described this first energy services PFI in the local authority housing sector as “a groundbreaking initiative which would dramatically expand the boundaries of resource procurement in council housing”.

Powerminster, meanwhile, claims the project complements a range of works aimed at securing the long-term future of the tower blocks and through the introduction of domestic chp reduces harmful emissions, particularly CO2.

The scheme recently won first place in the Focus on Energy Use category of the 2000 Labour in Local Government Awards. And Powerminster is confident that chp schemes will proliferate as more people become au fait with such matters as the Climate Change Levy and the PFI.

Who knows, the government, if it gets a second term, may put its money where its mouth is. After all, who do you suppose provided the following soundbite? “We want to see real improvements in industrial and domestic energy efficiency; and greater use of chp.” Anthony Charles Lynton Blair, no less.