District Heating & Cooling Networks

Heat Networks Investment Project

BEIS is promoting district heating system with its massive £320m Heat Networks Investment Project which opens for applications from the public and private sectors from Autumn 2018.

In 2015 DECC announced that it would allocate £320m to a new Heat Networks Investment Project to promote district heating systems as a method of reducing carbon emissions from heating.

In 2015 DECC envisaged that most new district heating networks would be based on Combined Heat and Power ("CHP") energy centres providing high temperature water to a set of buildings through heavily insulated metal pipes. The advantage of local electricity generation is that the heat generated as a by-product of generating electricity could be used to heat buildings instead of being wasted to the atmosphere. The combined result is that a greater proportion of the energy in the fuel is converted into useful electricity or useful heat.

However, the heat generated is likely to be wasted in summer and so CHP district heating does not always produce the benefits described. There is also the problem of heat being used to heat up the ground by the underground piping: this can be reduced by installing heavily insulated pipework, although the cost of this can be excessive.

A further issue is that CHP is also based on combustion which not only emits CO2, it also emits NOx, SOx and particulates which are a serious risk to health in urban environments.

CHP for district heating has been overtaken by events

In practice the use of CHP for district heating has been overtaken by events. The successful programme to decarbonise the electricity grid means that the optimum route for decarbonising heating has moved from combustion of gas in district heating networks towards using heat transfer.

Much lower distribution temperatures are used in Heat Sharing Networks – eliminating heat losses to the ground. Ground source heat pumps are used in each building to extract heat from the communal ground array whenever a building needs heating.

With improvements in the build construction of modern buildings, many commercial buildings need cooling in summer. A CHP district heating system is not able to provide cooling unless a second set of separate insulated pipes are installed to distribute cold water for cooling. This duplication is seriously expensive.

Fifth Generation District Heating and Cooling Network

There is a much more natural alternative: where ground source heat pumps have been installed in a Fifth Generation District Heat Network using ambient ground temperature distribution, the same heat pumps can be engaged in reverse to reject heat to the communal network and provide cooling.

Heat Networks Investment Project

BEIS now plans to accept applications for grants and loans to support new investment in heat networks – or extensions to existing heat networks – from Autumn 2018 in both the private and public sectors.

If you would like help in planning a new Balanced Energy Network then you give us a ring on 020 7482 5704.