Decarbonising Hot Water: The Continuing Role of Natural Gas

Rinnai Director Chris Goggin investigates the ability of natural gas to cover all domestic requirements whilst the national task of decarbonisation continues. Natural gas is still integral to UK domestic and commercial property heating and hot water provision. Find out how natural gas can power the UK through decarbonisation aims.

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The UK remains heavily dependent on natural gas to heat properties and provide hot water. Official energy statistics indicate that gas remained the principal source of UK electricity generation in 2024 at around 30.4% of total generation, although renewables reached a record share overall (Department for Energy Security and Net Zero, 2025; Department for Energy Security and Net Zero, 2024). Industry and government data also show that boiler replacements continue to dominate the heating market, even as heat pump deployment is increasing from a lower base (MCS, 2024; Department for Energy Security and Net Zero, 2026).

Policy direction in England has been moving towards low-carbon heating in new buildings through the Future Homes Standard, which was announced to phase out fossil-fuel heating such as gas boilers in new homes and replace it with cleaner technologies, subject to final implementation timetables and building regulations (MHCLG, 2019).

Although policy and grant support are accelerating heat pump adoption, gas boiler replacements still outnumber heat pump installations by a substantial margin in the existing stock. This means standalone gas boilers and systems are likely to continue playing a prominent role in UK heating in the near term, particularly in retrofit markets (MCS, 2024; Department for Energy Security and Net Zero, 2026).

Natural gas is therefore likely to maintain a role in UK energy demand for the foreseeable future, even as the system decarbonises. Britain’s gas network remains extensive, with around 285,000 km of transmission and distribution pipework serving roughly 23 million properties, which explains why proposals for transition often focus on managed repurposing or staged reduction rather than rapid abandonment of infrastructure (Business Energy Deals, 2026; House of Commons Library, 2024).

Hybrid technologies are another area of heating decarbonisation. In principle, a hybrid system can combine a boiler with a heat pump so that households and businesses can reduce emissions without moving immediately to a fully electric solution, which may not always be practical because of technical, economic or property-specific constraints (Carbon Trust and Rawlings Support Services, 2016; Energy Systems Catapult, 2025).

A hybrid heating system typically accepts two separate sources of energy, most commonly electricity via a heat pump together with natural gas or LPG via a boiler. These systems are designed to optimise performance according to variables such as outside temperature, current energy prices, and space-heating or domestic hot water demand (Carbon Trust and Rawlings Support Services, 2016; SGN, 2025).

Using two energy sources in a single system can offer benefits for end users. One potential advantage is financial flexibility: where electricity prices are relatively high compared with gas, a well-controlled hybrid can help moderate running costs while still lowering emissions. Capital expenditure may also be lower than that of some full-electric retrofit options, depending on property characteristics and the extent of wider fabric upgrades required (Climate Change Committee, 2022; SGN, 2025).

In operational terms, a hybrid heating and hot water system combines technologies so that the heat pump can meet a larger share of demand in milder conditions, while the boiler can support peak loads or colder weather. In this way, the system can balance efficiency, comfort and resilience when correctly specified and controlled (Carbon Trust and Rawlings Support Services, 2016; Energy Systems Catapult, 2025).

This configuration can optimise the strengths of each technology under different weather and demand conditions; in particular, combustion-based water heating can help support domestic hot water performance where instantaneous or peak demand would otherwise be challenging for an all-electric system without further upgrades (Carbon Trust and Rawlings Support Services, 2016).

A further benefit for the end-user is that both lifecycles of each technology is lengthened. As each technology does not have to apply full effort to satisfy demand, component and overall system longevity will be increased due to a lessening of required workload.

Hybrid systems can therefore offer a practical transitional route towards emissions reduction. Where projects cannot fully decarbonise immediately because of practical, economic or technical constraints, combining renewable and conventional technologies may provide a staged pathway that lowers carbon while maintaining service continuity and user choice (Climate Change Committee, 2022; Energy Systems Catapult, 2025).

Natural Gas still maintains a role in the landscape of UK energy consumption and will do for the foreseeable future. Traditional forms of fuel are hugely relevant in the current phase of active usage and will also be prominent if hybrid technologies are widely adopted. This means that even when fossil fuels are being substituted for cleaner energies and technologies, traditional fuels will still play a significant role in heating and hot water provision. 

For support with your next retrofit project contact the Rinnai design team today https://www.rinnai-uk.co.uk/contact-us/help-me-choose-product

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References

Business Energy Deals (2026) Gas transmission and distribution networks in Britain. Available at: https://www.businessenergydeals.co.uk/blog/gas-distribution/ (Accessed: 19 May 2026).

Carbon Trust and Rawlings Support Services (2016) Evidence gathering – low carbon heating technologies: Domestic hybrid heat pumps. London: BEIS.

Climate Change Committee (2022) Independent Assessment: The UK’s Heat and Buildings Strategy. London: CCC.

Department for Energy Security and Net Zero (2024) Digest of UK Energy Statistics (DUKES) 2024. London: DESNZ.

Department for Energy Security and Net Zero (2025) Digest of UK Energy Statistics 2025: annual data for UK, 2024. London: DESNZ.

Department for Energy Security and Net Zero (2026) Heat pump deployment statistics. London: DESNZ.

Energy Systems Catapult (2025) Electrification of Heat Demonstration Project. Available at: https://es.catapult.org.uk/project/electrification-of-heat-demonstration-project/ (Accessed: 19 May 2026).

House of Commons Library (2024) Households off the gas-grid and prices for alternative fuels. London: UK Parliament.

MCS (2024) 2024 is the best year on record for certified heat pump installations in the UK. Available at: https://mcscertified.com/2024-is-the-best-year-on-record-for-certified-heat-pump-installations-in-the-uk/ (Accessed: 19 May 2026).

Ministry of Housing, Communities & Local Government (2019) Housing Secretary unveils green housing revolution. London: GOV.UK.

SGN (2025) Hybrid Heating Systems: Accelerating Decarbonisation of Britain’s Homes. Available at: https://sgn.co.uk/sites/default/files/media-entities/documents/2025-11/Hybrid%20Heating%20Systems_Accelerating%20Decarbonisation%20of%20Britain's%20Homes.pdf (Accessed: 19 May 2026).

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