Zoning in: the new Heat Network Zoning consultation

The government is aiming for 11% of heat in the UK to be supplied by heat networks within newly designated heat zones. Alex Smith looks at the routes to connection in the new Heat Network Zoning consultation

The government has published Proposals for Heat Network Zoning ahead of plans to introduce heat network technical standards and mandate the connection of certain buildings by 2025.

The proposals, published in December, are intended to bring heat networks into the mainstream and create a viable route for occupiers to decarbonise their properties.

Identifying the lower-cost solution to decarbonising heat will lift the barriers to sector investment, the government says.

Justin Etherington, energy consultant and UK lead for the London energy team at Buro Happold, agrees that cost is key: ‘Heat networks will only succeed if they are competitive on cost and carbon compared with the customer’s alternative solutions.’

Other government initiatives around heat networks will also be vital, says Etherington. ‘Technical standards, policy support and standardisation of approach – as well as the introduction of Ofgem as the regulator – are all key elements in creating confidence.’

The proposals

The government is advocating the creation of a new Heat Network Zoning Authority (Central Authority), which will oversee all heat networks and coordinate zones in England, and Zoning Coordinators, which will implement zoning policy, and work with local authority planning departments.

Central to heat zones

The Central Authority will develop a standardised national methodology to identify heat network zones across England. It will assess the relative scale, value for money, project deliverability, and other such factors of different opportunities. 

The zoning methodology consists of two states: a mapping exercise to identify potential heat network zones across England; and a refinement stage, in which local Zone Coordinators will review and refine the outputs with input from local stakeholders. The Central Authority will establish a pipeline of opportunities, looking 10 to 15 years ahead.

The government envisages that local enforcement will be carried out by the Zone Coordinator. This will include issuing compliance notices, investigating non-compliance, imposing penalties, and providing for an appeals process. The Zone Coordinator will issue a penalty notice requiring the relevant person to rectify the breach or pay a fine. 

Building owners may apply to the Zone Coordinator for exemptions from connection. These will include incompatible heating systems and buildings tied to existing heating supplier contracts.

To encourage investment, the government is proposing that certain buildings in zones connect to a heat network. These will be: new buildings that receive planning permission after designation of a zone; pre-existing communally heated buildings; and other non-domestic buildings that meet certain criteria.

The proposals state that zoning should encourage local authorities and other public bodies to connect their estates to heat networks because it is a cost-effective way to decarbonise. 

Baxi sales director Stephen Hart says it is notable that some housing developers are already choosing community heat networks for larger estates where it is financially more attractive than installing individual heat pumps and associated hot-water cylinders.

‘It would be even more attractive to connect these developments to larger heat networks, where they exist, as the developer can avoid the need to install and operate a local low carbon energy centre,’ he says.

Pre-existing homes with individual heating systems will not have to connect, but Hart says it can make financial sense. ‘Heat networks could prove popular in low-rise, low-density upgrade projects as a cost-effective alternative to individual heat pumps,’ he adds.

Emissions limits

The government is proposing that heat networks in zones will be required to comply with national emissions limits from 2030, and is seeking views on three proposals for this limit – 44g, 83g or 147g CO2e/kWh.

Etherington would opt for the stricter limit: ‘The 44g figure seems a reasonable number for new networks that have the opportunity to start with low carbon sources.’ 

Baxi would advocate for the highest possible carbon intensity at the outset, but with a reducing intensity threshold over time, says Hart, who notes that the current maximum carbon intensity for schemes to qualify for funding under the government’s Green Heat Network Fund is 100g CO2e/kWh. This allows for hybrid energy centres with a low carbon primary heat source, such as heat pumps, to be combined with a boiler to satisfy peak demand.

Gas-burning boilers in hybrid systems could migrate to hydrogen or direct electric as technology evolves and the electricity grid is reinforced and expanded, adds Hart. 

The government estimates that heat zones could supply 11% of UK heat under its preferred policy option. This means that 70% of buildings that are not required to connect to a heat network in a zone will have to connect voluntarily. For this to happen, the government will have to win hearts and minds, says Etherington: ‘There will need to be significant education and engagement with customers to ensure they are confident in connection to heat networks in zones.’