Case study: Developing heat network opportunities across Barnet

Case studies · News · 15 Sep 2026

What is the project?

Project stage: Plan and Prepare

The London Borough of Barnet is developing a borough-wide heat decarbonisation programme focused on three priority areas: Hendon, Finchley and Colindale.

The project built on existing feasibility studies in Hendon and Finchley and extended the work to Colindale, assessing the technical, commercial, financial and delivery aspects of potential heat networks.

Colindale opportunity area

The Colindale feasibility study assessed several low-carbon heat supply options, including:

• air source heat pumps (ASHPs)
• aquifer thermal energy storage (ATES) with water source heat pumps (WSHPs)
• gas boilers for peak demand and backup supply.

The study demonstrated the scale of a potential heat network within the wider programme. It identified:

• a project area of around 200 hectares
• a development pipeline of more than 16,000 homes
• estimated connected heat demand of around 50 GWh per year
• a peak heat load of approximately 19 MW.

These findings provided a clear indication of the infrastructure required and the conditions needed for a viable scheme.

Zero Carbon Accelerator support

The Mayor of London’s Zero Carbon Accelerator supported the project through:

• feasibility studies for Hendon, Finchley and Colindale
• stakeholder engagement and market testing
• consideration of procurement and delivery models
• development of a Strategic Outline Case (SOC).

The project also used data from the LAEP DataHub to build a detailed dataset of buildings within the study areas, including information on existing heating systems and cooling demand. This evidence informed the feasibility assessments and helped identify potential heat network opportunities.

One of the most significant outcomes was the shift from separate feasibility studies to a project-level approach. This enabled Barnet to compare opportunities across the three areas and gain a clearer understanding of:

• the viability of different opportunities
• commercial and delivery challenges
• suitable delivery models
• future procurement and funding requirements.

Chris Smith, Assistant Director – Estates at Barnet Council, said:

“We were delighted to receive Zero Carbon Accelerator support for our heat network projects. Their work has been instrumental in helping us to:

• explore the viability of heat networks within the borough
• upskill council officers with regards to innovative low-carbon solutions and
• consider the most effective and financially sustainable delivery model for any future heat network projects.

We look forward to working with them again on future energy efficiency initiatives for the borough.”

Funding opportunities identified

The National Wealth Fund provided critical friend support to the London Borough of Barnet, helping to inform and strengthen the development of the Strategic Outline Case.

As heat networks are capital-intensive infrastructure projects, Barnet Council is unlikely to fund delivery directly. Instead, the emerging approach is to retain strategic influence while limiting direct financial exposure.

A joint venture or “golden share” model is currently considered a promising option. Under this approach, a private sector partner would finance, build and operate the network, while the council would retain strategic oversight and protections for the public interest.

The project also identified potential future funding sources, including the Green Heat Network Fund and other forms of concessional finance, which could improve scheme viability and affordability.

Challenges and learning

Finding suitable energy centre locations

Finding suitable sites for energy centres was a major challenge. Sites needed to be close to heat demand, large enough for equipment, meet planning requirements and fit delivery timescales. Identifying locations that met all these criteria in a dense urban area proved difficult.

To address this, the project team assessed multiple potential locations, worked with the council to understand site constraints and future development plans, and tested alternative energy centre options within the feasibility studies to identify the most practical and deliverable solutions.

Stakeholder alignment

Heat networks rely on enough customers connecting to make them viable. This required coordination across multiple organisations, developments and investment programmes. While stakeholders engaged positively, differing delivery timescales created uncertainty around future connections.

To address this, the project team engaged potential customers and key stakeholders throughout the study, developed an understanding of their growth plans, investment programmes and delivery timelines, and explored opportunities to align future network development with these plans. Where appropriate, non-binding letters of intent were secured to demonstrate potential customer commitment and provide greater confidence in future heat demand and network viability.

Regulatory uncertainty and delivery risk

The evolving policy and regulatory landscape for heat networks also created uncertainty when developing long-term commercial and financial cases.

To address these challenges, the project team:

• engaged stakeholders early and throughout the process
• refined technical and commercial options as the work progressed
• focused on realistic and deliverable solutions
• adopted a programme-wide approach that considered all three opportunity areas together.

This helped create a more strategic response to shared challenges and constraints, enabling Barnet to compare opportunities across the three areas, identify common delivery and procurement requirements, and develop a coordinated approach to future investment and implementation.

Energy and carbon impact of the project

The analysis identified potential savings of approximately 3,245 tCO₂e per year. Actual savings will depend on which schemes proceed, their final design, customer connections and the delivery model adopted.

What comes next?

The programme has provided Barnet Council with a robust evidence base and a clear understanding of the opportunities, challenges and requirements associated with heat network delivery. This places the council in a stronger position to make informed decisions about future investment and implementation.

Key activities are expected to include:

• progressing governance and decision-making processes
• developing the preferred commercial and delivery approach
• continuing market engagement and exploring procurement options
• refining technical, financial and commercial assumptions
• engaging with key stakeholders, prospective customers and organisations that could benefit from future heat network connections
• exploring funding opportunities and delivery partnerships
• progressing detailed design, construction and commissioning for schemes that move forward.

How could this be applied more widely?

One of the project’s main strengths is the development of a repeatable borough-scale approach to heat network planning and delivery.

There is also scope for future expansion where neighbouring developments or adjacent growth areas could support larger and more viable networks.

The project exemplifies ambition, collaboration, and innovation, supporting Barnet’s net zero future and providing a blueprint for similar initiatives.