HEXHAM HEAT NETWORK - FEASIBILITY STUDY & CONCEPT DESIGN

SYCAMORE NET ZERO

BACKGROUND

d3associates took part in several community energy workshops in Hexham, where one of the ideas identified for further exploration was the creation of a community-owned energy hub and heat network centred on the former Middle School site. Following these workshops, Sycamore Net Zero - a Community Interest Company focused on supporting the town’s journey to net zero - appointed d3associates to carry out a feasibility study.

The initial brief centred on the Middle School site but was later expanded to consider the potential for a town-wide heat network. As part of the work, a previous feasibility report was reviewed to build on the research and analysis already completed in Hexham.

OUTCOME

The feasibility study was delivered in a series of stages, beginning with an assessment of potential anchor loads and local heat sources. Working closely with Sycamore Net Zero, we identified properties with consistently high heat demands - including the hospital, leisure centre and local schools - which together represented around a third of the town’s total heat demand (estimated using postcode-level gas consumption data).

A wide range of potential heat sources were then assessed. These included waste heat from a local manufacturing site, surface water source heat pumps, heat recovery from the sewage treatment works, and electric and gas boilers for peak and backup supply. Each option was reviewed against a PESTLE framework (Political, Economic, Social, Technological, Legal and Environmental) to provide a balanced comparison.

Potential sites for an energy centre and network routes were explored, including options for river and rail crossings. A concept design was then modelled in nPro software, featuring a biomass CHP as the primary heat source supported by electric boilers.

This design was tested through a 40-year techno-economic evaluation, producing internal rate of return (IRR) and net present value (NPV) projections. Several alternative concept designs were also modelled to compare against the base case.

Despite operating within a very restricted budget and tight timescales, the project was successfully delivered on schedule thanks to close collaboration with the client. The final report was completed in time to support Sycamore Net Zero’s application for Green Heat Network Fund (GHNF) commercialisation funding - a critical next step in advancing Hexham’s ambitions for a low-carbon heat network.