Scottish Government

Case Study 1

Description of Project

The use of combined heat and power ( CHP) in multi-storey blocks "fuel poverty proofs" those flats into which this type of heating is installed. The Victorian Tenement Project works towards achieving affordable warmth for people who live in this most difficult to treat house type.

A high proportion of citizens living in fuel poverty in Aberdeen live in one or the other of these 2 house types, which together make up some 16,800 homes in the city.

Combined Heat & Power in multi-storey blocks of flats:

Inefficient heating systems are still to be found in the Council's multi-storey blocks. In total there are 57 multi storey block containing some 4500 flats.

In 2001/02 the Council carried out an options appraisal to identify the best way of achieving:

• a substantial improvement in the NHER of these flats,
• reduction of carbon emissions,
• achieving affordable warmth for the occupants,
• and do this in a way that is affordable to the Council in capital terms.

This recommended the installation of combined heat and power ( CHP) into clusters of multi storey blocks. In 2002 the Council set up Aberdeen Heat & Power Co Ltd. ( AH&P), as an independent, not-for-profit company, to develop and manage CHP schemes.

CHP is a very efficient way of generating electricity and heat together. A CHP plant is an installation where there is a simultaneous generation of electric power and useable heat, in a single process. It generates electricity locally and captures the heat produced to provide space heating and hot water. Fuel, usually gas, is used to run small generators that produce the electricity. This power is used close to the point of generation to run lights and appliances - any surplus can be offered for sale.

The heat is a by-product and provides a community heating system. CHP is around 85% efficient, in contrast to the 35% efficiency achieved by conventional power stations.

CHP systems are accredited producers of 'green' electricity - reducing the use of fossil fuels and reducing CO2 emissions, which are major contributors to climate change.

Stockethill

The council successfully applied to the Energy Saving Trust's community energy programme for capital grant funding and received £736,000, which was 40 per cent of the capital costs of developing the Stockethill CHP scheme.

In 2003 an energy centre was built close to one of the four multi-storey blocks, housing a 210 kilowatt electric (kWe) gas fired reciprocating engine CHP unit and two 700 kilowatt thermal (kWth) gas fired boilers for peak load and back-up. The heat is distributed to the four blocks via pre-insulated underground pipes, which comprise the heat network, with each flat having a new internal distribution system. The electricity produced by the CHP unit is traded by arrangements put in place by AH&P. Some occupants of the flats served by the heat network are supplied with electricity branded as AH&P, some is sold to other customers in the area, with the balance sold to Green Energy.

Prior to the installation, those in sheltered blocks were paying up to £7.80 per week for their heating and water, and tenants in the general needs housing up to £15. In addition, each householder used an average of 2000kWh of electricity per year, at a cost of £181. Immediately following the introduction of CHP, tenants began to pay a flat rate of around £4.75 per week for 48 weeks per year for heat and water. Those choosing to buy their electricity from Aberdeen Heat and Power paid approximately £159 per year. This represented a total fuel cost of £387 per year, or just £7.44 per week, against costs of up to £18.48 per week before CHP.

Hazlehead

Aberdeen City Council has ploughed more than £700,000 into the Hazlehead scheme from the city's Housing Capital Programme; with much of the remaining funding coming in the shape of a £600,000 grant from the Community Energy programme.

The new heat network in Hazlehead links not only more than 200 homes, but also Hazlehead Academy and the adjacent swimming pool. In addition to the four housing blocks Deanseat sheltered housing will join the network. The provision plays a key role in ensuring the council's own homes in the community meet the Scottish Housing Quality Standard.

Seaton

Work is already underway to deliver Aberdeen Heat & Power's third network in Aberdeen - serving around 500 homes in Seaton. Aberdeen City Council has committed £1.86 million from its Housing Capital Programme to bankroll the ambitious £3.38 million scheme, covering six multi-storey blocks. A further £1.3 million was secured from the Community Energy programme.

Project Outputs

The 3 CHP schemes will result in 14 of the 57 blocks (i.e. 800 of the 4500 multi-storey flats so far) being fitted with wet heating systems from central CHP plants. In addition 7 Council owned public buildings have been linked into these CHP district heating schemes.