Preparing for the UK’s first retrofit heat network

Swaffham Prior is a rural community in East Cambs developing a local heat network for the village. The move to replace the oil-fired and electric heating systems in houses and other community buildings with low-carbon heat.

Swaffham Prior Community Land Trust commissioned a Rural Community Energy Funded feasibility study in 2017, and subsequently developed the scheme in partnership with Cambridgeshire County Council (CCC).

This scheme is unique in the UK as a “retrofit” heat network, and has huge benefits for the community.


Benefitting the local community

Benefits include cutting carbon emissions in the village by two-thirds by replacing local oil boilers with centralised ground-source heat pumps supplying a heat network, reducing the cost of heating and avoiding price volatility for residents. There are also “co-benefits” like reducing oil deliveries to the village and installing superfast broadband alongside the network.

This heat network project is an important pilot for other rural off-grid communities who need alternatives to oil but may not be able to afford to install individual heat pumps. CCC received funding from the Heat Network Delivery Unit (HNDU) to progress the scheme from initial feasibility to detailed project development.

To ensure the successful delivery of this time-critical project, CCC appointed Avieco to act as their project manager for the development of the scheme.


Building trust

Our team of project managers worked with the local authority stakeholders and others to fully understand the project and to engage the community and build trust for this complex, long-term infrastructure project.

We provided key support to the project board to ensure the smooth delivery of development and commercialisation phases of this complex project. This included secretariat support to the project board, liaison with HNDU and other central government officers, and translation of technical outputs and decisions for the community and other non-technical stakeholders.

One important function was coordinating the other contractors; our managers maintained close communication with both these contractors and their wider teams, collating and reviewing progress reports, action logs, and risk registers. This supported good decision making by the project board and ensuring that work was completed on time and to spec.

Engaging the wider community

At the start of the project, we needed to engage the wider community to secure sign-ups for the scheme. We worked closely with the community engagement lead, developing and distributing project materials, including presentations and posters, and attending workshops, public meetings, and other events to communicate the benefits of the scheme and how the community could get involved. After six months of community engagement activity, over half the community signed up to the scheme. We continue to receive new expression of interest for this scheme every week.

Technical appraisal

As well as confirming the village’s appetite for the scheme – the “heat demand” for the project – we also needed to confirm the “heat supply” available. The scheme is designed to extract heat from a land parcel belonging to CCC using ground source heat pumps and boreholes. The team had completed some desk-based studies of the topography of the land, but had not yet conducted any direct testing at the site. To do this, the team commissioned a test borehole – drilling one 200m hole into the land, and assessing how much heat could be extracted from it. This test showed how many boreholes we would need to supply the whole village with the heat it needed.

heat networks - drilling

Test borehole drilling July 2019 – Courtesy of Cambridgeshire County Council

Accessing support for development and commercialisation

The first stage of the project demonstrated that there was sufficient support for the scheme in the village, and that there was enough heat available from the land earmarked for the ground-source heat pumps.

With this evidence, Avieco applied to HNDU again for more development funding to complete the planning application, detailed mechanical, electrical and pipework design, and legal and commercial advice on the structure and financing of the scheme. This was awarded in December 2019, and the next phase of work mobilised in the new year.

As this work continued into 2020, and with the approaching deadline of March 2021 to get the project delivered, we advised the board on when to apply for their construction funding from the Heat Network Investment Project – a sister fund to HNDU. We completed this application in April 2020, to seek funding for the final stages of commercialisation, including the Investment Grade Proposal, legal structuring, contracting with households, and discharging planning conditions; and also for support for the construction costs.


Swaffham Prior setting a key example for many local communities

We have developed a compelling case for Government’s ongoing support for the project as a strategic priority, to facilitate the delivery of this scheme – to benefit Swaffham Prior and the tens of thousands of other UK households off the gas-grid who need to decarbonize their heat supply rapidly. This is a key pilot site – paving the way for other communities to develop similar schemes and access support from suitable project partners.

For more, see the project video here.

If you’re interested in more projects supporting rural communities in becoming more sustainable, read what we did for Burnham Parish Council here.

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