Written evidence submitted by BEAMA (DHH0114)
BEAMA is a trade association representing over 150 manufacturers across heating and ventilation, smart energy, building electrical infrastructure and energy networks sectors. As such we provide insight on a wide range of aspects of the net-zero challenge and identify interrelations between them. However, we are responding to this inquiry to advise the Committee on two focussed aspects of heat decarbonisation: first, better controlled heating systems, and second, use of lower carbon heat sources.
Improving heating systems can reduce emissions today by making existing systems more efficient. It will also future-proof homes for low carbon heat sources by reducing the amount of heat needed (through mains gas or other fuels) and preparing homes for the technical changes needed. Finally we believe that addressing system issues is a useful gateway to engaging consumers on heat decarbonisation and allows them to plan for more significant changes to their homes in future.
We have identified a hierarchy of measures that have the potential to reduce this heating load by 22.6% overall through improving heating controls. Further improvements to systems can be made by improving hot water provision and building fabric. Combined with changes to controls the total reduction in fuel used in gas heating system could be as much as 50.6%. The ways to implement these changes will be through Building Regulations Part L, by ensuring that policies reinforce each other by requiring improvements to controls when installing other measures, open communications systems, and improvements to product standards.
Changing heat sources is a necessary measure for reaching net-zero. We have focused this section recommendations to address the barriers to uptake of heat pumps. Heat pumps can form part of a highly efficient zero carbon heating system, facilitate energy system flexibility, and combine well with other desirable technologies such as solar PV, underfloor heating, energy storage and EV charging.
In our detailed comments below we review evidence and make recommendations on awareness, knowledge, suitability, money and new homes. A consistent and ambitious programme to prepare homes for zero carbon heat sources is needed. We do not yet know how far clean hydrogen will be suitable for use in the 85% of homes on the existing mains gas grid. To ensure we do not leave it too late to upgrade homes, we must prepare for a significant rollout of heat pumps and we must begin this structural planning now.
Here we briefly answer some of the other specific questions of the inquiry.
The success of the 2050 target is dependent on industry and businesses adapting to consistent and effective regulation ensuring the appropriate investment signals in the market. In 2019 research our members reported that the incentives for them to invest were wavering due to lack of consistent policy ambition. Where subsidies are needed and provided, they must tackle the most fundamental issue. Where a market-based approach is taken, externalities relating to emissions must be taken into account. Government must recognise that every opportunity missed to implement positive changes will only make it harder to rectify in future.
Beyond the recommendations in this paper, several other issues must be addressed, including consumer awareness and engagement, improved skills and training for a low carbon heat supply chain, fabric of buildings, fair pricing for electricity, availability of finance and better recognition and reward of improved energy performance of homes.
The distribution of levies does not reflect carbon content of fuels. Electricity is partly far more expensive than gas due to such levies. We do not have data on the best way to tackle this, but would advocate that levies on low carbon electricity generation are urgently reviewed.
There must be a strategy for informing householders of the need to plan to change their heating systems before 2050 as convenient trigger points occur only occasionally. This should be coupled with better access to advice on staging of energy improvement measures. Advance planning will be far more effective for householders than reacting only when an existing system breaks. This must start from the top – Ministers should use every opportunity to remind householders of the coming changes and consistently explain current policy, for example the plan to have minimum energy efficiency at point of sale of owner-occupied homes.
How a strategy for better controlled heating systems in homes could significantly reduce the cost of low carbon heating infrastructure
A strategy to optimise control and efficient operation of UK residential heating systems could significantly reduce the amount of energy required for heating, and therefore the infrastructure cost of providing decarbonised heat. This paper shows that:
The same system measures would provide immediate benefits for the energy efficiency of existing homes.
A range of policy levers are also suggested in this paper that could be used alongside a roadmap for systems in the Heat and Buildings strategy to achieve the potential benefits in practice.
The energy used by a heating appliance, such as a boiler, is largely dependent on the overall system. In this context, the system comprises both the additional elements such as emitters and controls and the way it is designed and commissioned. While commissioning is required under the current Building Regulations it is known that practice is poor and enforcement is weak.
Decarbonising heat in UK homes is expected in large part to require a transfer from (largely) gas to either electric heat pumps or hydrogen. Both require the development or upgrading of infrastructure for production and distribution, and both use fuels that will potentially be more expensive to consumers than the current unit price of gas. Hence, reducing the size of the heat load that is required in UK homes can offer a significant benefit by reducing the infrastructure cost to Government and the end cost to consumers.
There are two additional benefits from system improvements. Firstly, the improvements envisaged will immediately reduce carbon emissions from gas boiler fed systems in existing homes and help meet energy efficiency reduction targets. Secondly, these improvements can help make homes ‘future ready’ as they are largely consistent with the installation needs of heat pumps, and will deliver similar energy efficiency benefits with hydrogen boilers as they do with gas boilers.
Figure 1 below shows the potential impact of applying a range of system improvement measures to all home heating and hot water systems on the overall energy required for gas heating and hot water:
The amount of natural gas used for heating and providing hot water to UK homes in 2019 was 25.7 million tonnes of oil equivalent (mtoe) of which 19.8 mtoe is for heating. The following actions have the potential to reduce this heating load by 22.6% overall, and are presented as a recommended hierarchy of application against which to apply potential percentage savings:
3.1 Individual room temperature controls
The role of TRVs (thermostatic radiator valves), and other forms of individual room temperature controls, is to reduce waste heat from rooms that can overheat where the only temperature control in a home is a single room thermostat. As such, it is a reasonable first step to take as it is simply reducing the amount of heat needed to keep homes at the desired temperature.
Tests carried out at the University of Salford by BEAMA to a specification provided by BRE showed that the prevention of overheating by TRVs could reduce gas consumption by an average of 18% over the heating season. A study by the European Building Automation and Controls Association estimated that a programme to replace manual radiator valves and older TRVs could lead to an overall reduction in UK energy consumption by 7%.
3.2 Compensating controls
Conventional room thermostats send a simple on/off signal to the boiler. They turn the boiler on when the temperature falls below the setpoint, and off again when it rises above setpoint. With load compensation the thermostat adjusts the output of the boiler in relation to the predicted heating needs. Weather compensation is similar but also includes outside temperature data in the calculation. Both result in closer control of temperature and more efficient boiler operation and this will be independent of any user interaction.
BEAMA have commissioned two phases of tests at the University of Salford on load and weather compensation. As a minimum, this shows that the UK could reduce boiler energy consumption by 5% if all room thermostats were upgraded. However, this figure applies in tests where the boiler had already been significantly tuned (see item 3 below). Tests without tuning indicate a greater annual savings potential of up to 12% from the controls alone applied to an in-situ boiler. We have used the lower value in this analysis until a wider verification is completed.
3.3 Boiler tuning
In the second phase of the University of Salford tests described above an experienced installer undertook the following work prior to the commencement of the test programme:
• Assessed the boiler size against the design heat load for the building and selected a boiler with a suitable modulation range to operate efficiently at expected part loads
• Range rated the boiler to the calculated dwelling heat loss
• Set the boiler pump speed at maximum and minimum based on calculated mass flow rates
• Balanced radiators to ensure a 20oC temperature difference across the radiators when the room temperatures were at the designed levels.
All of the above are expected to be deliverable by heating installers but require additional information, refresher training and extra time to be spent on an installation. It is already a legal requirement for replacement boilers to be commissioned, which would ideally include all of the above, and these skills need to be developed and utilised for future low carbon heating.
We are still in the process of verifying the total savings impact of these actions (it wasn’t originally an objective of the tests.) However, a direct comparison of the baseline (on/off thermostat) tests in the two phases shows that 17% less gas was used in the Winter tests, and 31% less gas used in the Spring tests. Allowing for some of the variables (to be further analysed) we are using a conservative savings potential of 7% in this paper.
3.4 Converting systems to low temperature operation
As well as being a necessary element for future heat pump connections, it is well known that existing gas boiler systems will run more efficiently at low temperature operation. Most gas boilers are currently installed into high temperature systems so changing to low temperature emitters (e.g. larger radiators or underfloor heating) could be expected to make an overall saving of 2.4% consistent with the efficiency reduction for low temperature operation of a boiler in table 4c of SAP2012.
3.5 Smart (behavioural) controls
This category covers the commonly accepted definition of a smart control laid out in the BEIS Boiler Plus FAQs as products that let consumers remotely control their home temperature via a tablet, smartphone or desktop, with a common understanding that a ‘smart’ product requires some form of wider connectivity. The Boiler Plus definition also requires some element of learning.
Acknowledging the above, it is also clear that the widest uptake of smart controls currently is with devices that act to more closely match overall on/off operation of the heating system with occupancy, either by allowing users to adjust the operation when they are not home, or by sensing and responding to occupancy. Within this proposed hierarchy of system measures this would be the last step; limiting the operating time of a system already optimised for efficiency.
Field trials on smart thermostats indicate overall potential savings in gas consumption of 6%. There are likely to be some element of savings within this for the improved control accuracy of a replacement thermostat, as well as optimum start functionality which currently gets a credit within SAP 2012. There is also some uncertainty over the impact with an optimised low temperature system running for longer periods. However, we believe it is reasonable to assume a saving potential of 3% across the housing stock – particularly with a clearer definition of required functionality.
3.6 Smart (flexibility) controls
These are not included in the calculations as the focus is on gas, but it should be noted that there are potential benefits from smart controls for heat pumps, and other electric heating, that allow heating appliances to take advantage of variable time of use tariffs to reduce the cost and carbon intensity of the electricity used. There is some evidence that UK heat pump users scheduling their heat pumps to avoid peak hours have seen average prices of less than 8p/kWh compared to the average of 15p/kWh. A long-term strategy for heat should include the role of such controls, both for the consumer benefits and the beneficial impact of grid flexibility.
As described in section 3, improving heating systems can have a significant impact by reducing the amount of energy required for residential heating. However, this approach should be part of a wider strategic focus. As mentioned above, the total annual gas consumption for residential heating and hot water is about 25.7 mtoe and figure 2 below shows how this could be reduced by over 50% by implementing system improvements on top of a different approach for hot water and achieving the Committee on Climate Change’s recommendations for fabric energy efficiency improvements.
4.1 Hot water
Of the total gas used in homes by boilers, approximately 23% of that is to provide hot water. The predominant trend currently is for combination boilers delivering instantaneous hot water, but there are other options that may be preferable for a low carbon future and a key component of this would be the re-incorporation of hot water storage in homes.
With a hot water cylinder, or alternative form of storage, a home can utilise renewable energy to provide hot water (either on-building or local) alongside an immersion heater connected to time of use tariffs to heat water tank when low cost, zero carbon electricity is available. Correctly controlled, this could then minimise the contribution of main heat generator in the home (either hydrogen boiler or heat pump) and reduce the hot water component of the current heating load.
Field trials have shown that solar water heating systems can provide 60% of a household’s hot water needs. With advances in technology, particularly in photovoltaics, it is likely that this can increase. The degree to which flexible tariffs can offset water heating load required from the heat generator is yet to be determined but it is know that BEIS are funding a trial working towards the gradual electrification of water heating through a combination of home solar PV, and flexible tariffs. Reductions in tank and pipe losses could also play a small part. In this document we have assumed that an 80% reduction in the current gas usage for domestic hot water is possible.
The major difficulty with this approach would be the need to incorporate hot water cylinders in homes when many of these have been removed. It is estimated that 70-80% of homes no longer have a cylinder and occupants could be resistant to loss of space. However, there are many challenges to decarbonise homes and this could be one of the more practical to resolve. In addition, this would make homes heat pump ready and could provide a clear cost benefit to householders when hot water becomes increasingly significant in well insulated homes and where the future cost of zero-carbon energy sources is uncertain. While there is an implication on the electricity network, this could in theory remove a large part of the current heat generator load and should be analysed.
4.2 Fabric energy efficiency measures
The Committee on Climate Change’s Further Ambition scenario show the potential for a 25% reduction in energy demand as a result of fabric efficiency measures. Given that fabric measures are about insulating and improving the airtightness of buildings their impact is to directly reduce the heat load of homes and should therefore be included in this analysis.
The aim should be for all system upgrades to be done by 2040. This would ensure that efficient and future ready systems are available for the final stages of heat decarbonisation as well as maximising the carbon saving benefits of these measures within the existing housing stock.
The following policy levers have potential to help deliver these measures:
5.1 Building Regulations Part L
Heating systems are one of the significant areas that can be influenced by Building Regulations as there are about 1.6 million boiler replacements each year where the regulations will apply.
Increasing the regulatory requirements at the time of boiler replacements too far could have obvious negative effects. The majority of boiler replacements, approximately 70%, could be described as a ‘distressed purchase’ where the boiler has failed or is not working properly so adding costs to a necessary purchase will be a burden to consumers and could potentially delay the replacement of inefficient appliances. However, there are reasonable improvements that could be made immediately within the regulations for existing homes due to come into force in 2021:
The Heat and Buildings strategy should lay out a plan for progressive increases in the minimum standards that will be required when a boiler (or other element of a heating system) is replaced. In addition it would be helpful to have higher levels of ‘good practice’ defined in parallel to the minimum standards, with an insistence that these higher levels are applied when any financial incentives (such as a Government funded grant scheme) are being used for the work.
5.2 Defined heating measures for incorporation into financial incentives
One of the issues for incentives, such as the Green Homes Grant scheme in England, is that heating system measures can be quite poorly defined.
With a clear roadmap for system improvements, and a defined list of packages of measures (e.g. those in sections 3.1 to 3.5). Government would be in a better position to incentivise these heating improvements either on their own or alongside boiler replacements.
5.3 Requirements for open communication standards
One of the barriers to the wider application of load and weather compensation controls that communicate with the boiler (see section 3.2) is that there are different approaches within industry over the application of communication protocols. This can make it harder for installers to ensure compatibility, and can create a significant barrier where installers want to combine controls and boilers from different manufacturers, which is a common scenario in the current heating installation market.
There is an open communications protocol specifically for boilers and compensation controls called OpenTherm. This is widely used by manufacturers in other EU countries, most notably in the Netherlands where around 90% of boilers installed have a communicating compensating control facilitated by an OpenTherm communication.
Government could make it a requirement for controls and boilers to have open, or compatible, communications, much as it has done with smart meters and is working on for smart appliances. Introducing such requirements has the ability to transform the number of boilers installed with more efficient control, even without further regulation. It should be noted that the high proportion of modulating controls in the Netherlands is market led rather than a regulation.
5.4 Product standards – modulation ratios
Following the end of the transition period the UK is known to be reviewing product policy, including the current EU Ecodesign and Energy Labelling requirements for boilers. One aspect that could certainly benefit from more prominence is detail of the modulation ratio of boilers. In essence, the higher this ratio, the greater the ability of the boiler to ‘turn down’ its heat output in response to part loads when controlled by a compensating control. The aim should be for this ratio to get close to a nominal ratio of 10:1.
A desktop study by BEAMA, looking at technical details of all residential boilers on the website of a well-known wholesaler showed that the average ratio was less than 5:1, with only 8% of boilers having a ratio of 7.5:1 or better. Also, this information was generally difficult to access.
It would be helpful for better information to be provided on this to installers, both to identify better performing boilers and to understand why it is important. More prominence for this figure could also drive better product performance.
The barriers to uptake of heat pumps mostly fall into four categories for existing homes, particularly on the gas grid:
37% of the UK population thinks they have not heard of ‘net-zero’ (BEIS PAT Wave 34, Aug 2020). 48% are not aware that gas boilers are a source of CO2 emissions (BEIS PAT Wave 31, Sept 2019). We can conclude then that many householders are unaware that the heating system in their home will need to change by 2050, and will not be planning how to do this.
Recommendation: Consumer awareness must be increased now so that householders can begin to plan for changing their heating system. Government should follow the CCC recommendation to fully embed net-zero in all policy areas. Government can also launch awareness campaigns, work with consumer organisations, and provide materials for organisations with large consumer reach.
43% of the UK public have not heard of renewable heating systems (BEIS PAT Wave 32, Dec 2019). Most would only consider changing a heating system when it breaks down (BEIS PAT Wave 32, Climate Assembly report Sept 2020), which may also mean they are not actively planning for a new heating system and therefore unlikely to be researching alternatives to their existing heating technology.
Around 30% of people say they know something about ASHPs or GSHPs (BEIS PAT Wave 33, Jan 2020). There have been occasional stories in national newspapers about heating technologies (e.g. The Times, 2 Nov 2020). However, mainstream sources of information about heat pumps remain sparse. The Government’s Simple Energy Advice website is quite new, and in our view does not contain sufficient detail or information that would convince somebody to choose a heat pump if they were not already considering this.
Recommendation: Government should continue to improve the SEA website and signpost more consumers to trusted advice.
Other ways of increasing knowledge among the public about heat pumps would be word of mouth or information from tradespeople, two of the more trusted sources of information. While the uptake of heat pumps remains low compared to gas boilers, the scope for word of mouth knowledge is limited. Similarly there are relatively few tradespeople working with renewable heating; installer skills and knowledge are reportedly limited in general, and this will limit the level of information tradespeople give to householders about heat pumps.
Recommendation: Government should pursue the easiest opportunities for wider deployment of heat pumps as soon as possible – especially new build, where retrofit barriers are absent, and Government has power to require low carbon heating through Building Regulations. Government should make renewable heating the default in all public procurement and building projects.
Renewable heating, aside from those most knowledgeable or supportive, tends to be discussed in negative terms – avoiding emissions but with a significant cost as a trade-off, and something that needs to be done rather than something that is beneficial to a householder. The wider benefits of heat pumps for a householder, which would show them to be a positive alternative to a gas boiler, tend not to be widely discussed. These would include:
Recommendation: Government to take a wider approach to heating through its advice and forthcoming Heat & Building Strategies, allowing the benefits of combining improvements to heating with on-site generation, storage and transport to be realised.
One aspect of suitability is how installation of a new heating system fits into a person’s lifestyle. Most would only consider changing a heating system when it breaks down (BEIS PAT Wave 32, Climate Assembly report Sept 2020), either for convenience or due to not wanting to waste a working system. Coupled with lack of awareness of the need to change, this suggests currently a lack of planning of when to change a heating system, thus making choice of a heat pump less likely for many people.
Many householders would install a heat pump at a certain trigger point. While heat pump systems can be installed relatively quickly, many will take longer than say replacing a gas boiler. As such for many it may make most sense to install a new heating system when moving into a new home or as part of a package of renovations. As these events may occur only rarely, some householders would not see a convenient opportunity to install a new heating system.
Recommendation: Consumer awareness must be increased now so that householders that reach a trigger point are aware of the benefit of changing their heating system at the most convenient time and a potentially rare opportunity to reduce emissions is not missed. Government to support improvement to heating systems to make them renewable-ready.
Another barrier is the energy efficiency of homes. As with all heating systems, a heat pump will operate most efficiently if a home is well insulated. While EPC ratings, one proxy for the energy efficiency of homes, are improving across the UK’s housing stock as a whole, many homes remain poorly insulated, which is perceived as a barrier to heat pump installation. However, our members have had heat pumps installed for a wide variety of buildings, including historic buildings, so the shortfall here is possibly more about bespoke advice rather than simply a matter of insulating homes.
Recommendation: Government to support industry work to improve skills and advice. Government to accelerate requirements to improve energy efficiency of homes.
A barrier for some homes will be the availability of space for either an ASHP or GSHP. Larger communal heat pumps could be suitable for some of these homes.
Recommendation: Dissemination of information and learning from communal heat pump projects and Government to provide advice to Local Authorities and housing associations.
Householders who rent their homes lack the power to install a heat pump. While landlords have some obligations to improve the energy efficiency of their homes, there is currently no mechanism to require them to install higher efficiency heating systems.
Recommendation: Government to encourage and support landlords to install renewable heat as well as energy efficiency.
Heat pumps have a higher upfront cost than gas boilers. The Green Homes Grant scheme running until March 2021 is not the ideal mechanism for supporting installation of heat pumps, despite the useful financial contribution, due to the tight timescales. The proposed Clean Heat Grant that would start in 2022 when the RHI ends again would be a useful contribution. However, as things stand even with either of these grants a consumer could still end up paying more for a heat pump than they would for a replacement gas or oil boiler. Those replacing oil boilers may also need to factor in the costs of decommissioning that system. Many consumers would see a heat pump as a direct substitute for a gas boiler, rather than offering additional aspirational benefits (though there are potential additional benefits as detailed in item 2), meaning they may be reluctant to pay more than needed for a heating system.
Recommendation: Government to communicate to those interested in GHG about the RHI that will remain available until 2022, and the Clean Heat Grant that will be available from 2022, to retain any interest generated by the GHG.
For those with a heat pump that do not have on-site renewable electricity generation, the price of electricity could be a significant issue for running costs. There are some heat pump tariffs available. However compared to the price of mains gas electricity prices are high. This is not reflective of the lower carbon content of mains electricity compared to mains gas, and the associated externalities from higher carbon fuels.
Recommendation: Government to ensure the lower externalities of lower carbon fuels are rewarded. Government to work with financiers, energy retailers and Ofgem to ensure there are no barriers to development of specific heat pump tariffs. Government to update Simple Energy Advice website to notify consumers of any specific heat pump tariffs.
Use of finance products for heating systems is relatively low compared to use of finance for products such as cars, homebuying and other home renovations such as kitchens. While the finance industry is planning trials of new financial measures, coordinated by the Green Finance Institute, it remains to be seen what consumer uptake might be, especially when set aside desire to use finance for other more desirable products.
Recommendation: Government to ensure that consumers taking out any Government financial support for heat pumps are also permitted by Regulations to take out other financing options.
For Ground Source Heat Pumps, consumers are expected to pay for the full installation. However, there is a disparity with other heating technologies, where consumers do not pay for all external pipework and connection costs, particularly if some of this can be shared with adjacent homes. Some believe that ground source heat pump infrastructure such as ground loops can be seen as national infrastructure with a long lifespan, and that householders should not have to foot the bill for this infrastructure that would outlast their residency, given that it currently acts as a cost barrier.
Recommendation: Government to work with key stakeholders to determine how best to install ground source heat pump infrastructure, recognising pipework as infrastructure and ensuring that costs are distributed fairly.
For new homes, the chief barriers are the lack of regulation requiring low carbon heating, and the wariness among some developers to install low carbon heating. However, the cost of installing a heat pump for a new home is lower than in an existing home – estimated at £3134 for a house (see Impact Assessment from Future Homes Standard Consultation).
Recommendation: Government to make Building Regulations more ambitious by opting for the Options of greatest carbon reductions in the response to the Future Homes Standard consultation and close loopholes, as one of the fastest ways to move heat pumps into the mainstream.
 BEIS Energy Flow Chart 2019 https://www.gov.uk/government/statistics/energy-flow-chart-2019 corrected by removing 3.4% of the total to account for gas cooking using percentages of consumption in the UK Housing Energy Fact File 2013 (BEIS)
 Study by the Behavioural Insights Team on the savings from smart thermostats, 2017: https://www.bi.team/publications/evaluating-the-nest-learning-thermostat/2
 The pathway to net zero heating in the UK - A UKERC policy brief (2020)
 UK Housing Energy Fact File 2013 (BEIS)
 Here comes the sun: a field trial of solar water heating systems - The Energy Saving Trust (2011)
 Based on installed base and rate of change recorded in the UK Housing Energy Fact File 2013 (BEIS)
 Net Zero –Technical report, Committee on Climate Change (2019)
 Research report - Homeowners' Willingness to Take Up More Efficient Heating Systems By Ipsos MORI and the Energy Saving Trust for DECC (2013)
 It should be noted that this is not strictly an ‘open’ protocol as users have to be members of the OpenTherm Association. However, as the costs are used primarily for development this is not generally seen as a barrier.