Joe Dart, Head of Content for the Plumbing and Heating Exhibition (PHEX), provides an overview of the options for the future of heating as we move towards the UK’s 2050 net zero emissions target.

With the Government’s legally binding target for net zero carbon emissions by 2050 on the horizon, local authorities are increasingly having to consider the environmental impact of their property portfolios.

A natural starting point for many local authorities seeking to embrace net zero is to evaluate how they are heating their buildings. For context, domestic heating accounted for 18% of all of the UK’s greenhouse gas emissions in 2021.

The UK has relied on fossil fuel boilers for decades, so councils need to be aware of what options they have when it comes to future-proofing their assets.

Heat pumps

Heat pumps, and air source heat pumps in particular, have in recent years been positioned as the successor to gas boilers. Energy Systems Catapult’s Electrification of Heat Demonstration project, funded by the UK government, found that ‘there is no property type or architectural era that is unsuitable for a heat pump’.

This, in part, has given the Government the green light to introduce several schemes aimed at increasing the number of heat pump installations. Although the flagship Boiler Upgrade Scheme can’t be accessed by local authorities, there are other initiatives that will help fund heat pump installations.

In December 2023, the Government announced a new local authority retrofit scheme which plans to allocate £500m to support up to 60,000 low-income and cold homes, including those off the gas grid. In addition, the Social Housing Decarbonisation Fund was allocated £1.25bn to support up to 140,000 social homes to be retrofitted, which includes funding for heat pumps.

Heat networks

Heat networks (also known as district heating) distribute heat or cooling from a central source or sources and deliver it to a variety of different customers such as public buildings, shops, offices, hospitals, universities, and homes. By supplying multiple buildings, they avoid the need for individual boilers or electric heaters in every building.

This is another technology that has been favoured by government in recent years. Although market share for heat networks as of 2022 was below 3%, the aim is for this to grow to 20% by 2050.

Last year, the Government earmarked more funding for heat networks, including the Green Heat Network Fund, which will provide £485m to help up to 60,000 homes and buildings access affordable, low carbon heating through new heat networks. It also introduced the Heat Network Efficiency Scheme, which allocated £45m to improve around 100 existing heat networks.

Hybrids

A solution touted by manufacturers of heating products especially is that of a hybrid heating system. Hybrids, in this instance, typically refer to the combination of a gas boiler and a heat pump in one heating system.

The idea is that the heat pump takes on most of the heating load, with the gas boiler there to support when the heat demand is significant enough, or when hot water is needed.

Heat pumps require a separate hot water cylinder to deliver hot water around a heating system, so in a hybrid a combi boiler can instead step in and provide this.

Funding for hybrid heating has been earmarked in the Social Housing Decarbonisation fund, suggesting that it will play some kind of role in government’s plans for net-zero.

According to the scheme guidance: ‘Funding may be used to install hybrid heat pumps for homes currently heated by mains gas, whether this is; a new hybrid system made of several units, or fully integrated within a single unit; or a heat pump alongside the current gas boiler that has an Energy RelatedProducts rating of A (or above), where the retrofit coordinator is satisfied it is in good working order to be fitted alongside a heat pump.’

However, it adds: ‘Prior to installing a hybrid heating system, retrofit coordinators are encouraged to upgrade existing systems to stand alone heat pumps, where possible.’

As such, hybrid systems are probably best viewed as a stepping stone on the journey towards net-zero, or for those instances where it would be particularly challenging to install a heat pump or other low-carbon system without adversely affecting output.

Hydrogen

Hydrogen has been touted as a potential low carbon solution for heating for a while, however enthusiasm for the technology has declined in recent years.

Major projects to determine hydrogen’s viability in Redcar and Whitby were scrapped by the Government last year, leaving just one remaining trial in Fife, Scotland, where 300 properties will be converted from natural gas to green hydrogen systems.

The Government is expected to make a final decision in 2026 on whether hydrogen has a role to play in the heating of certain properties, so for local authorities looking to take action now, that may be too long to wait.

To find out more about the future of heating, including the outcomes of Energy Systems Catapult’s Electrification of Heat Demonstration project, register to attend either PHEX South or PHEX North now.