The UK government is targeting 600,000 heat pump installations a year by 2028. This presents a major opportunity to lower carbon emissions of homes across the UK, while making homes more comfortable and cheaper to heat. However, the increase in electrical consumption this causes presents challenges to our local and national electricity networks. HeatNet aims to alleviate these challenges through smart, coordinated solutions.
What is HeatNet?
HeatNet is a collaboration between UK Power Networks, Passiv UK and Imperial College London, supported by Ofgem’s Strategic Innovation Fund. The project explores how smart controls can help manage local electricity network constraints caused by heat pump adoption, particularly in new housing developments and suburban housing estates.
Most energy flexibility projects to date have focused on large-scale, national grid balancing. HeatNet flips that approach by looking at what happens at the ‘grid edge’, the final few steps of the electricity network, between the local substation and people’s homes. Low-voltage networks such as these pose a unique challenge, ensuring the electricity supply is secure while minimising costs for householders.
Heat pumps can heat homes and hot water without emitting any CO2, but because they shift heating from gas to electricity, they significantly increase the electrical demand of the home. When this happens at a large scale, like an entire estate, this can put significant strain on the local grid. Historically this has been solved by upgrading the local transformers and electricity cables. However this comes at a cost for the networks and households, so now network operators are looking for new, innovative ways to address this challenge.
There are two key challenges HeatNet will address: capacity constraints and voltage drop.
Each transformer (the device that transfers electricity from the high-voltage to the low-voltage networks) has a certain power capacity within which it can safely operate. Higher capacities are more expensive to build, and with more and more heat pumps being installed, requirements for this capacity are constantly rising.
Voltage drop occurs within the local network. As multiple properties connected to the same cable draw power, properties further down the line don’t receive the electricity they need. This occurs in the home as well. If you have multiple high power devices, such as a dishwasher and washing machine on the same circuit, running them both at the same time can prevent either of them working correctly. On a larger scale, multiple heat pumps on the same cable running simultaneously can mean none of them operate as efficiently as they could be.
How does HeatNet work?
At the heart of HeatNet is a smart optimisation platform that coordinates how and when heat pumps operate across a neighbourhood. Each home is fitted with the Passiv Smart Thermostat, a smart, connected heat pump control device which offers flexible operation while maintaining user comfort. This both feeds into, and is fed by, an aggregated control algorithm which takes into account both the requirements of the home and those of the wider network.
By utilising a range of information including capacity limits and voltage drop data, the HeatNet system can automatically shift and adjust heat pump consumption in response to local network requirements. This ensures that homes across a given estate operate within safe thresholds and do not risk compromising electricity supply through voltage drop.
The result? Reduced peak loads, better voltage stability and less need for costly infrastructure upgrades.
The project recently wrapped up its Alpha phase, having demonstrated the cost savings HeatNet can provide to DNOs and households alike. Passiv and the other project partners will continue to explore how coordinated optimisation of low carbon assets can support local grids, developing plans for real-world commercialisation and deployment. Passiv and UK Power Networks will also look at expanding currently available DNO data sets to further support the HeatNet solution.
For local flexibility, coordinated control can provide an invaluable service to ensure the stability of our distribution networks. HeatNet is providing a framework for this next generation of network management.
