Can district heating networks help support green heating across the UK?
July 2022

Across the UK and globally, governments, developers, energy companiesand homeowners are being forced to ponder the way residential and commercial properties are heated due to growing concerns around the impact that traditional heating methods have on the environment. As traditional methods need replacing and many methods are being considered as a solution for the green heating revolution, district heating and the usage of heat interface units are a potential solution that has many benefits including being sustainable in character.

Why is there a need for a clearer plan on greener heating?

The UK government has made its intentions to decarbonise the country clear, with heating methods an area under high scrutiny. Plans to ban gas boilers in new homes from 2025 and the introduction of the green homes grant have kickstarted the process to implement greener heating solutions across the UK, but there are still a range of issues that need solving before we can get to a stage where the country is ready to tackle a new era of heating.

Eligibility is an issue facing the government when identifying which green heating methods and energy sources are to lead this revolutionary green charge. Different property types and needs mean that leading options like ground and air source heat pumps aren’t suitable for mass roll out to all properties and other potential options like hydrogen or geothermal sources aren’t advanced enough to follow the same capacity of roll out. From the surface, it appears there is no one size fits all approach to the green heating revolution.

Cost is another area that is highly criticised and limiting, regarding the number of homes and businesses that can afford greener heating sources. The government’s green home grants and investments in the delivery of the greener heating sources has helped but is still believed there isn’t enough being done to make these sources accessible for everyone.

The cost and eligibility of green heating present significant constraints in society, but these are both problems that look to persist for some time to come. As a result, it is likely that a combined approach of renewable energy options and energy efficient heating methods are needed to kickstart this green heating revolution. The introduction of district heating networks and heat interface units (HIUs) may be a part of this combined solution.


What are heat interface units and what is district heating?

HIUs are boiler substitutes which provide the same ability to provide central heating and domestic hot water to dwellings. These heat interface units are typically installed on each single dwelling within a multi-property complex, such as an apartment block or assisted living area. Heat interface units are a common integration into district heating networks.

District Heating involves a central location where supply water is heated and generated for distribution to a network of residential and commercial properties within an enclosed area. The heat is transferred to the properties for water and spatial heating through a network of pipes before being retransferred back into the same network and being reused in the centralised district heating plant. Their reuse of resources and compatibility with renewable energy sources make them an ideal solution for sustainable heating.


What makes HIUs and District Heating a more sustainable and desirable option than traditional heating methods?

Sustainable heating is much easier to access through a communal heating network like district heating because there is greater feasibility to use renewable energy sources. With a conventional boiler, the heat source remains the same. On the other hand, with a district heating network the heat source is much more flexible meaning a range of non-renewable and renewable energy options are compatible. As pressing demands continue to rise for greener heating solutions to be adopted, this makes district heating offers a promising solution for new developments.

Heating networks in Europe have been much more frequent in function and spoken about in their successes, with Copenhagen in Denmark a prime example as the city looks set to achieve carbon net-zero targets by 2025. 30% of Denmark is heated through the burning of plastic waste that could be recycled no other way and 50% of the country is heated through similar district heating processes.

District heating is a relatively new concept in the UK; however, there are examples of plans for this green heating solution to be implemented and cases where it has been a success. Bristol is the latest city to announce plans to create a district heating network centrally within the city to work towards net-zero goals. These plans look set to use a range of different renewable sources to decarbonise the city including the usage of sewer water. There has been a lack of district heating networks in the UK as the development and implementation of such solutions can be quite expensive in areas that are already built-up. In contrast, this cost is less prevalent in the development of new dwellings and properties as these areas are yet to be built.

Because of their high energy efficiency, heat interface units play a key role in district heating from a sustainability perspective. Combined with renewable heat sources, a highly efficient unit makes the perfect combination for sustainable and effective heating of new and existing buildings.

Heat interface units, like Calefa, offer intelligent machine learning which after two weeks can memorise a household’s energy usage patterns. Therefore, optimising the amount of energy used and ensuring a comfortable indoor climate for residents. This makes the Calefa unit a market leader for intelligence and energy efficiency.

Alongside the sustainable character of HIUs and district heating, there are a range of other features and benefits that make them a desirable option for greener heating solutions including:

Instead of having separate energy sources, everyone in one area uses the same source meaning energy costs are cheaper as they are split between all residents.
Heat interface units use machine learning to understand inhabitant’s uses of energy, meaning energy usage is maximised
Repairs and maintenance are easy identifiable and rectifiable as the central source is powering the heating and hot water supply of everyone within the district.