District Energy - the next piece in the net zero carbon puzzle?

23rd January 2020

As the UK looks to become net zero carbon by 2050, with many local authorities pledging targets to be net zero by 2030, the challenge of meeting the UK’s low carbon heating and cooling needs is becoming ever more pressing.

by Dr Andy Davey,

Traditional heating and cooling sources are struggling to meet these needs and, with technology advancing every year, a flexible approach to heating and cooling is needed if we are going to meet the UK’s net zero carbon needs, both now and in the future. This is where District Energy comes in - providing a technology agnostic solution that allows heat sources to be changed and updated as technology develops, future proofing schemes with minimal disruption to residents as we move towards zero carbon. 

The challenge of decarbonisation 

How do you heat and cool a neighbourhood or entire city at the same time as reducing its CO2 emissions? It’s a challenge facing many local authorities, and one that can be addressed by the use of district heating and cooling systems. At the heart of these systems is an Energy Centre, which serves a range of buildings through a network of underground pipes and cables, utilising energy from gas combined heat and power (CHP) or other low and zero carbon (LZC) technologies such as fuel cells, biomass, solar thermal or heat pumps.

As district heating is usually connected to large volume demands, either by way of big buildings or high volumes of smaller buildings such as residential properties, it facilitates investment in the recovery of heat from less conventional heat sources, such as rivers, sewers, industry or waste treatment plants which wouldn’t be practical for individual buildings to access.

In this way, we can apply low carbon heating and cooling solutions to large areas of dense urban landscape that would be hard to otherwise decarbonise and utilise these more innovative energy sources to provide their heating and cooling needs.

Engaging the public sector

The Committee on Climate Change has suggested that around 18% of heat in buildings will need to be supplied by heat networks by 2050 if the UK is to meet its carbon budgets cost effectively [1]. However, to meet this target we urgently need public sector engagement in schemes to make them viable.

Public sector engagement in the schemes is useful as the large loads from public buildings, such as libraries and health centres, can give a good base for the schemes to be built out from.  However, there is no requirement on these buildings to connect and there have been good schemes that have fallen to the wayside due to the inability to get the public sector loads connected. The Scottish Government is looking to rectify this issue when they look at the Heat Network Regulations in 2020. If they do, they will be leading the way in the UK in terms of facilitating district energy as a solution to tackle the problem of decarbonising.

Putting it into practice

ENGIE has 16 district energy networks throughout the UK, most of which are in partnership with a local authority. All of our networks are being assessed for their carbon performance and the opportunities for delivering greater carbon savings in the future. Our new projects are all designed with a view to utilising the best possible low carbon energy source and, where possible, allowing for potential future technologies to be included, future proofing the schemes as we move towards net zero carbon.

In partnership with Newcastle City Council, we are using District Energy as a low carbon and cost-effective energy solution, providing all business and homes on the landmark Newcastle Helix urban regeneration scheme with affordable heat. This pioneering partnership is expected to help significantly in the council’s carbon reduction targets.

While District Energy has a part to play in the decarbonisation of the UK’s heat and cooling requirements, it is by no means a panacea. However, in dense urban environments and where there is a heavy load across large buildings, such as university campuses and hospitals, it can offer a viable solution to the challenge of saving carbon while still effectively heating our homes and businesses. 

If we are to meet the UK’s zero carbon targets, we need heating solutions which lower carbon heating sources can be readily plugged into as technology develops, and District Energy offers just that, and could be one of the many missing pieces in the puzzle as we move towards net zero carbon.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/766109/decarbonising-heating.pdf

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