The Department for Energy Security and Net Zero (DESNZ) consultation on the future of the Boiler Upgrade Scheme (BUS) has closed, the Institution of Gas Engineers and Managers (IGEM) has reported. The scheme provides grants for heating systems in homes and non-domestic buildings1. The consultation gave Future Energy Networks (FEN) and the wider industry the opportunity to argue that hybrid heating systems should be included in the scheme as soon as possible1.
Hybrid heating systems typically consist of a boiler, either existing or replacement, with the addition of a small electric heat pump. The heat pump element provides most of a home's heating, with the boiler called upon only in certain circumstances, such as when it is exceptionally cold or renewable generation is very low1. FEN states that installing a hybrid system today can reduce gas consumption by up to 80% and carbon emissions by almost 100% when using a tariff supplying low carbon electricity and entirely renewable gas1.
FEN, whose chief executive James Earl wrote the blog, argues that hybrids require far fewer changes in the home than a solely electric heat pump, with no requirement to upsize radiators, change pipework or find space for hot water storage1. It cites a trial by Intergas Heating Ltd in the Netherlands covering 174 homes over two winters, which found a 75% average reduction in gas use and average annual savings of €1000 per household from optimising between electricity and gas use1. FEN notes this was a trial under different market conditions from the UK1.
On grid costs, FEN cites the Freedom Project trial, which it says showed that using hybrid heating systems saved a cumulative reinforcement cost for the South Wales electricity distribution system of around £1.3bn by 2050 compared with full electric heat pump systems1.
"A Department for Energy Security and Net Zero consultation on the future of the BUS, which provides grants for heating systems in homes and non-domestic buildings, recently closed."
The consultation's opening date, closing date and the number of responses have not been reported. DESNZ has not published its response to the consultation, and no decision on whether hybrid systems will qualify has been announced1.
Why it matters for households
The Boiler Upgrade Scheme pays a grant towards the cost of a heating system, and which technologies qualify determines what a household can claim for. Hybrid systems have historically not qualified1, so a home that keeps a boiler alongside a small heat pump has not been able to draw on the grant in the way a fully electric installation can. The eligibility rules are therefore the practical question behind the consultation, and the grant amount is fixed by the scheme rather than by the technology chosen.
For a home's energy independence, the argument FEN makes is about how much gas a property still draws and how much strain it puts on the electricity network. A hybrid keeps a gas connection in use, which FEN says can cut gas consumption sharply, while a fully electric heat pump removes gas use but can require insulation and other remedial work and a stronger grid connection. FEN also states that hybrids can switch heat demand off the electricity system in about a second for an indefinite period, which it describes as a flexibility service1. Whether any of this changes what a household can claim depends on the outcome of the consultation, which has not been reported.
What happens next
DESNZ has not published a response to the consultation, and no date for a decision has been reported1. FEN says it used the consultation to set out why hybrid heating systems should be included in the scheme as soon as possible1.