An Essex couple have become the first in the UK to heat their home using a mini data centre in their garden shed, in a trial designed to cut energy bills and support low income households through the transition to net zero.
Pilot Scheme
Terrence and Lesley Bridges live in a modest two bedroom bungalow near Braintree in Essex. Their home is owned by Eastlight Community Homes, a social housing provider, and they are part of a pilot run jointly by UK Power Networks and Thermify through an innovation project called SHIELD. The couple were selected for the pilot because they rely heavily on their heating, especially as Lesley lives with spinal stenosis and is in significant pain when temperatures drop.
Thermify HeatHub – Huge Savings
Since the installation of the Thermify HeatHub, their monthly energy costs have fallen from around £375 to between £40 and £60. Terrence said: “It truly is brilliant. I’m over the moon that we got picked to trial this out. You can’t fault the heating system, it is a 100 per cent improvement on what we had before.” Lesley added: “You don’t need to go to a sauna after coming here.” Their experience is one of the first real world demonstrations of a heating concept that blends clean energy, digital infrastructure and social support.
Who Is Thermify?
The heating unit in the Bridges’ shed is called a HeatHub. It is developed by the British company Thermify, which offers cloud computing services to businesses. Instead of housing its servers in a single large data centre, Thermify installs small clusters in people’s homes, where the heat generated by data processing is captured and used as low cost domestic heating.
The wider programme is actually part of SHIELD, which stands for Smart Heat and Intelligent Energy in Low income Districts. SHIELD is run by UK Power Networks through the Strategic Innovation Fund. Its aim is to help people who would normally be excluded from the shift to low carbon technologies because of high upfront costs. The project brings together Thermify, Eastlight Community Homes, community energy groups and technical partners to develop what they describe as a Social ESCo model. Under this model, equipment such as solar panels, batteries and HeatHubs is funded upfront by an energy services company and repaid over time through the value created by the technologies.
How The Data Centre In Their Shed Works
Inside the HeatHub are around 500 Raspberry Pi Compute Modules, all submerged in a special oil. As these computers run cloud tasks for Thermify’s business clients, the electricity they use becomes heat, which raises the temperature of the surrounding oil. That heat is then transferred into a heat store and the home’s central heating and hot water systems.
The principle is pretty simple. For example, computers turn electricity into information but all the electricity eventually becomes heat. Traditional data centres spend significant amounts of extra electricity on cooling systems that remove the heat and release it into the air. Thermify’s approach uses that unavoidable heat twice by turning it into a resource for the household.
A dedicated network line is installed so the unit can send and receive data without affecting the resident’s broadband. From the resident’s point of view, it behaves much like a boiler, controlled through familiar heating settings. The Bridges’ shed also contains a solar inverter and a battery, meaning their HeatHub is part of a small integrated energy system that stores and manages electricity through the day.
Why It Cut Their Bills
In the Bridges’ case, the combination of the HeatHub, solar panels and battery storage has transformed their energy use. Thermify pays for the electricity needed to run the computing tasks because this is part of its service to business clients. The heat produced from this process is supplied to the home at a low or no cost because the energy is already being paid for. SHIELD tenants who receive HeatHubs also pay a small standing charge for heat, although UK Power Networks expects this to be significantly lower and more predictable than the cost of gas for many low income families.
Thermify points to independent modelling that suggests this kind of distributed computing could reduce carbon emissions from data centre operations by about 75 per cent on average. SHIELD’s own modelling suggests combining HeatHubs with solar and batteries could reduce household energy costs by 20 to 40 per cent and cut heating related emissions by more than 90 per cent.
Data, Energy And Tech Companies
The concept has clear implications for cloud and data centre operators. For example, data centres already account for roughly 2.5 per cent of the UK’s electricity consumption and the sector’s demand is forecast to grow rapidly in the next five years. As more companies expand into artificial intelligence and digital services, pressure is rising to reduce the environmental impact and find practical uses for the heat that data centres produce.
Distributed systems like Thermify’s also offer an alternative to building ever larger centralised facilities. Although HeatHubs cannot handle the heavy workloads required for advanced artificial intelligence, they can run many common tasks such as analytics, apps or batch processing. If rolled out at scale, the model could create a network of tens of thousands of small data nodes that serve business customers while heating homes. SHIELD itself has a long term ambition to deploy up to 100,000 such systems a year by 2030.
The approach may also interest energy companies and grid operators. For example, embedded assets such as HeatHubs can help manage peaks and troughs in local demand and provide flexibility services to the grid. SHIELD is exploring how these devices might be combined with peer to peer energy trading and other smart local energy systems.
Sustainability Advantages
There’s clearly an environmental case for improving overall energy efficiency and reducing reliance on fossil fuels. With up to 30 per cent of a data centre’s electricity used solely for cooling, capturing that heat and using it to warm homes can replace the need for gas and reduces the total energy wasted.
There are also potential social benefits to consider here. For example, many low income households cannot afford the upfront investment needed for heat pumps or solar installations. SHIELD’s Social ESCo model aims to solve this by funding the equipment and repaying costs through the value generated by the assets. Early stages of the project show strong interest among tenants who are worried about energy bills but keen to adopt cleaner solutions.
Not A Totally New Idea
It should be noted here that the idea of using data centre heat in buildings is not new. For example, in Devon, a startup called Deep Green operates a washing machine sized digital boiler at a local swimming pool. The servers inside the unit warm the mineral oil surrounding them and the captured heat is used to heat the pool. Reports indicate that the installation has reduced the pool’s gas use by more than half and cut emissions by dozens of tonnes of CO₂ each year. A recent investment from Octopus Energy aims to expand similar units to more than one hundred pools across the UK.
Also, another British company, Heata, attaches small servers to domestic hot water tanks. Homeowners earn a payment for hosting cloud workloads and the heat from the servers warms their water. In mainland Europe, district heating networks in cities such as Odense, Paris and Stockholm already capture heat from large data centres to supply nearby homes and offices.
Key Challenges And Criticisms
Although the Bridges’ results are positive, there are ongoing questions about reliability and long term performance. For example, HeatHubs depend on a steady demand for cloud computing. If business workloads fall or move to other locations there could be uncertainty about how much heat is produced and how backup systems would operate. Trials like SHIELD allow operators to test these scenarios before any wider rollout.
There are also some practical issues to consider. HeatHubs need secure network connections, scheduled maintenance and clear communication so residents understand how the system works. Social landlords also have to consider noise, space and safety. Early feedback from SHIELD has highlighted the importance of strong support and simple user experience.
There is also a broader debate about whether heat reuse can keep pace with the rapid growth in data centre energy demand. Artificial intelligence training and inference use far more electricity than the kind of workloads Thermify deploys. Even with heat capture, growing numbers of data centres will place pressure on local electricity networks. Policymakers and regulators are increasingly encouraging heat reuse but stress that it must be combined with wider grid planning and efficiency measures.
For now, however, the Bridges’ warm bungalow in Essex has become a test case for how computing and heating might come together, offering an early glimpse of a model that could reshape how data centres are built and how homes are heated in the years ahead.
What Does This Mean For Your Organisation?
The trial highlights how digital infrastructure and domestic energy systems can support each other, which is why it is gaining interest across the UK. Data centres are expanding rapidly as businesses adopt artificial intelligence and cloud services, yet their rising electricity use and waste heat are becoming harder to manage. A system that captures this heat and delivers it as affordable, low carbon warmth offers clear benefits for households and creates a more efficient model for the tech companies that rely on constant processing power.
There are important implications for UK businesses here. For example, a distributed network of small data hubs could give companies access to computing capacity with a lower environmental impact, supporting sustainability commitments while easing pressure on the wider grid. Energy providers and local authorities may also see value in systems that help stabilise local demand and offer predictable heating costs for low income residents.
The Social ESCo model is another key part of the story, as it removes the upfront cost barrier that prevents many households from adopting low carbon technologies. If the model proves reliable at scale, it could influence how social housing providers, councils and developers approach retrofit programmes and new energy installations.
Heat reuse is likely to become more common as the UK works towards decarbonising heat. Projects like SHIELD show how data processing, renewable generation and home heating can be combined in a practical way, although long term questions remain around reliability, workload availability and system management. Even so, the Bridges’ experience demonstrates how an integrated approach can reduce bills, cut emissions and provide a template that could be adapted for both homes and businesses in the years ahead.