'Heat network’ is an umbrella term that describes a shared network providing space heating and/or hot water to multiple buildings (district heating) or to multiple dwellings, often within a high-rise tower block (communal heating).

The source – or sources – of heat for these networks is a centralised energy hub that transfers the heat to the connected buildings or apartments through insulated underground pipework. 

Avoiding the need for individual heat sources in each dwelling or building, this can reduce the carbon intensity en masse, and improve energy security for users as new low-carbon heat sources are deployed. 

Heat networks are technology agnostic, therefore a natural gas or biomass boiler, a heat pump, or a hybrid approach may all be used for powering the energy centre. According to the Heat Trust, electric technologies such as heat pumps are the dominant heat source in new heat networks. The CIBSE code of practice, CP1, however, points to the benefits of a hybrid-engineered approach to ensure greater future reliability and security as demand on the electrical grid intensifies to, and perhaps beyond, capacity.

While this may not achieve full decarbonisation at the outset, a well-designed hybrid system will prioritise the heat pump’s contribution, with gas boilers providing the necessary energy resilience. 

Implementing the heat network infrastructure should be the priority to ensure energy security and efficiency with full decarbonisation of the heating source using technology such as heat pumps achievable at the end of the generation asset lifetime.

Campus heating

A campus heating system is a derivation of a district heating system where the heat generator is also the owner of the buildings, which are connected by underground pipes to a central energy centre. This type of network may be found in military bases, universities, and hospitals. 

While it isn’t a new concept in such a setting, existing infrastructures may be dated and inefficient. When decarbonising a campus heating system, the size, variety, and complexity of the different buildings involved, and their heating requirements, pose a challenge. 

The installation of a new system offers the opportunity to deliver a solution that will improve both economic and environmental sustainability, while providing greater energy security and resilience. Planning for that new system should also consider the possibility to scale it up to become a heat network hub for the wider local community; unlocking additional future opportunities to support decarbonisation.

Policy

The government has already made its intentions clear with regards to heat networks, setting an ambition for 20% of UK heat demand to be supplied in this manner by 2050; up from an estimated 2-3% today. Proposed heat network zoning legislation, which identifies and designates areas in the UK where heat networks would offer the most suitable low-cost solution to decarbonisation, would help increase uptake. 

In order to incentivise and support developers with implementing heat networks, government and private sector funding is available.

Steps to success

Whether for a high-rise block, a school campus, or a development of homes, there are a few key steps to take when deciding on a heat network to ensure the project’s success:

1. Carry out feasibility and design studies. Partnering with a specialist provider can provide the right support for each project and streamline the process. They will ideally be able to offer digital tools for pre-contract design advice, and solutions with low-carbon heat sources to support funding applications
2. Consider prefabricated options. To make the process of creating a low-carbon system smooth and seamless, consider heating solutions providers that can supply in-house off-site manufacturing and engineering capabilities to design and build the energy centre – including packaged plant room options
3. Plan servicing and maintenance. Using connected remote monitoring and control will allow for the optimisation of performance and precise maintenance. This will also facilitate predictive maintenance to limit downtime and disruption, with remote monitoring enabling service engineers and contractors to pinpoint root causes of issues and fix them early on.

As the number of heat networks across the UK grows in response to changing legislation, there is a big opportunity for heating engineers and contractors to get involved with their installation and maintenance. 

Working closely with a specialist, such as, for example, Baxi – following its recent launch of an end-to-end heat networks proposition, including heat interface units, thermal substations, prefabricated energy centres, and design and training support – will ensure they have access to the solutions and expertise to deliver sustainable, efficient, and reliable systems.