EVENTS | HEAT PUMP RESEARCH SEMINAR The study aimed to find out if householders would be willing to accept lower temperatures and, therefore, be open to making their homes suitable for low-temperature heat pumps . To understand if the campaign message hit home, Rossi evaluated the variation of the distribution of boilers with a flow temperature setpoint below, equal to or above 60oC between winter 2021/22 and winter 2022/23. The study revealed that, for a sample of 4,503 boilers over two years, the proportion of households that set their flow temp to 60oC doubled, from 3% to 6%. It is predicted the campaign may have impacted more than 400,000 dwellings in England, possibly saving more than 26 million in winter 2022/23. After the results were collected, a heat map was drawn up to look at the distribution of temperatures, which showed that most of the boilers were set at 72-75oC. It was found that 10% of combi boiler users reduced their setpoint temperature for the entire heating season. The average peak setpoint was reduced from 74 to 70. Although flow temperature was probably adjusted to deal with colder or warmer temperatures, this is not true for households that opted to set their boilers to 60oC. These results can be really useful for heat pump consideration. We can look at behaviour, and how willing people are to live with a system below 60oC, said Rossi. The findings suggest that, while many users were willing to reduce their temperature from above 60oC to a minimum of 55oC, fewer were willing to lower their thermostats further. Suitable for the switch UCL doctoral researcher Laurence Childs revealed that existing heating systems may be more suitable for heat pumps than previously thought. He analysed data from 4,600 boilers while on secondment at the DESNZ and found that heating systems may be able to operate at lower flow temperatures. IEA HEAT PUMP TECHNOLOGIES PROGRAMME Annex 56: Digitalisation and IOT for heat pumps Report showing comparisons between more than 40 connected heat pump projects. A webinar and slideshow from October 2023 is available. Annex 57: Flexibility by implementation of heat pumps in multi-vector energy systems and thermal networks The potential for the use of heat pumps in district heating and cooling, and how they can offer flexibility for electricity grids. Annex 58: High-temperature heat pumps Overview of technologies with analysis of case studies. One of the reports focal points is technologies that can provide process heat above 100C, a critical requirement for many industrial applications. European statistics show that 67% of the demand between 100C and 200C was directly covered by fossil fuels. The first part of the project looking at technologies was published in August. Annex 60: Retrofit heat pump systems in large non-domestic buildings Led by the UK, this project aims to provide high-level guidance for buildings owners and other decisionmakers. Report due in late 2024. Annex 61: Heat pumps in positive energy districts Investigating heat pump solutions for groups of buildings as positive energy districts. Existing clusters will be monitored and evaluated. Report due in 2025. Annex 62: Heat pumps for multi-family residential buildings in cities Focusing on heat pump solutions for new and retrofit multi-family houses in high-density cities. Eleven case studies have been added to the website, including four from the UK. The annex is a follow-up to Annex 50 Heat, which has more case studies and was completed in November 2022. Annex 63: Placement impact on heat pump acoustics Following on from Annex 51, this project will look at removing acoustic market barriers to heat pumps and will look at acoustics as more heat pumps are used for cooling in a warming climate. Details of all the projects can be found at heatpumpingtechnologies.org Measurements for the boilers were used to predict if radiator or fabric upgrades were needed for a heat pump to provide the same level of heat as set by the occupants. When averaging extracted heat demand over six hours, 31.5% of dwellings could operate at 55C or less without radiator upgrades. This is three times the amount that was estimated using surveys, suggesting that the costs and disruption of a heat pump could be lower than previously thought, with fewer radiators needing to be replaced. Childs noted that averaging heat demand over longer time periods can reduce the requirements for radiator upgrades, which demonstrates the value in changing heating patterns. He said peak flow temperatures were only necessary for a small proportion of the year, which indicates the potential for the installation of small supplementary electric heaters or hybrid heat pumps to reduce the burden of radiator and fabric upgrades. The findings could be significant, Childs said, because entire heat distribution systems can cost up to 7,500, creating a significant market barrier to heat pump adoption. Daniel Logue, adviser at Energy Systems Catapult, was the technical lead on the governments Electrification of Heat Demonstration Project. Part of the study looked to the technical and practical feasibility of a large-scale rollout of heat pumps across a representative range of housing types and social groups. In the project, 742 air source, hybrid and ground source heat pump systems were installed in a range of homes. Only 15% of these homes required a fabric upgrade to enable the heat pump solution, though 93% did have at least one radiator change. The seasonal performance factor (SPF) of each system was calculated. While the overall results were positive, Logue said quite a large variation was seen across all heat pump types, indicating that, while many people reported that the systems provided a comfortable temperature, too many were getting a poorperforming system. Logue suggested that the heat pump model may be one of the reasons for the variation, with newer models, running on R290 refrigerant, outperforming old models running on R410A. However, he highlighted other potential contributory factors, including the quality of the installation and design. The study found that heat pumps performed worse if they had a higher flow temperature, but there was no difference in performance between different house types or the age of a property. All of the homes were deemed suitable for a heat pump. Looking at the results, we 26 February 2024 www.cibsejournal.com CIBSE Feb 24 pp25-26, 28 Gov heat pump conference.indd 26 26/01/2024 16:42