To meet the government’s ambitious net zero target and reduce carbon emissions, we must take a joined-up approach to explore the most viable options for removing gas from design, to ensure that headway is made quickly to meet the deadlines, says Craig Harrison, operations director for modular contracts at Newtons Group
In June 2019, the government made a historic commitment to achieve net zero greenhouse gas emissions by 2050, followed by an update in January this year to the Clean Growth Grand Challenge, which aims to at least halve the energy use of new buildings by 2030.
Heating and powering buildings account for 40% of our energy usage in the UK, with around 18% of UK greenhouse gas emissions coming from homes, mostly from gas boilers, a significant contributor to air pollution.
To be in with a fighting chance of meeting the government’s ambitious targets, there needs to be a concerted and dramatic change from consumers and the construction industry. A damning report from the Committee on Climate Change (CCC) in 2019 stated that “UK homes are not fit for the future”.
According to Ofgem, only 4.5% of the energy used for heating the UK’s 29 million homes and other non-residential buildings comes from a low carbon source, a number that needs to vastly improve by 2050. The CCC analysis proposed that 90% of homes, and 100% of non-residential buildings, should be heated from a low carbon source, and that no new homes should be connecting to the gas grid by 2025.
The Future Homes Standard
The government’s plans to reduce carbon emissions from homes requires that by 2025, building regulations for new homes have low carbon heating systems, making gas (and other fossil fuel) boilers obsolete from newly built houses.
Originally published in 2019, The Future Homes Standard (FHS) was a response to the findings of the CCC report, putting building regulations and energy solutions under scrutiny. Updated in January this year, the FHS specifically talks about the measures newly built homes will need to put in place between now and when the legislation is officially implemented in 2025.
Looking at the alternatives
Switching to non-combustion heating systems will greatly reduce the harmful emissions generated by traditional gas boilers. Although it’s unlikely there will be a single solution for every home in the UK, as different areas are better suited to different approaches due to resource availability and housing types, the logical alternative to gas when it comes to modular is air source.
Air source heat pumps
Air source heat pumps work by processing natural heat transitions from air, into a fluid. The fluid then travels through the pump’s compressor where it is heated up, going on to then heat the home’s circuit to serve as a warm water source. Suppliers such as Vaillant and Ground Sun have developed pumps designed for use in a wide range of homes, from apartments to detached houses.
Niall Connell, director at Ground Sun, installers and distributors for heat pumps, said: “In addition to providing energy efficiency, the benefits of the Ground Sun 200 air source heat pump include lower fuel bills, low maintenance requirements and ease of installation.
“There are some negative perceptions that air source pumps take up a lot of room or are noisy,” Niall Connell goes on to comment, “but we have developed the Ground Sun 200 as a compact heat pump, which provides heating and hot water with no outdoor unit required.”
With one of the main KPIs of modular design being that as much of the work is completed offsite as possible, heat pumps such as these fit with this perfectly. Fitting and connecting the unit in the factory results in a significant cost saving, through reduced on-site labour and less on-site scheduling risk with other trades.
Electric boilers are more efficient than gas, with an efficiency rating of 99%, compared to 89%-95% for most gas boilers. Lower emissions, alongside the familiarity of electric, could be an advantage in terms of the end-user.
However, even though electric boilers can be efficient, they are three times more expensive to run.
To heat a hot water cylinder on an electric boiler will use a lot of energy, and as the cost of electricity is higher than gas, this is likely to be a more costly option for homeowners.
One way to offset the cost and help keep running costs down, could be to install solar PV panels, which can be used with a solar battery to generate energy and power most electric boilers day and night.
Ultimately, what the government decides to do in terms of subsiding costs for electric boilers, will influence what the industry does in terms of design and build.
Pushing sustainability through collaboration
As we currently stand, it’s unclear how this transition phase ahead of legislation in 2025 is likely to progress. As MEP specialists, Newtons are actively researching the options and conducting live trials, working with designers and developers to educate and advise. Housebuilder Redrow has also announced they will be trialling infrared heating at one of their sites later this spring, with the potential to roll it out if successful.
Harry Leeson, managing director at Newtons, explains: “If we all try and work this out in isolation, it’s going to be a much slower process. We need to work together, because 2025 isn’t far away and this is so important to get right.
“We’re doing lots of trials, but collaboration will be critical to accelerate our learnings and understand how we’re going to move forward – it’s not a lot of time for the industry to adapt.”
To be able to change in advance of approaching legislation, as an industry we should be asking questions and ensuring new systems are being included in modular design. At Newtons our collaborative approach means we have been able to move ahead with ways of understanding and developing the best solution for the replacement of gas and collectively building our knowledge.
Culturally, moving away from gas is a big change and moving towards more sustainable options is likely to progress in line with peoples’ understanding. With the news that the government’s Green Homes Grant scheme has been slow to take off, as an industry we must play our part in raising the profile of this important issue to keep the pressure on.