1 Introduction
1.1 Literature review
1.2 Principles guiding the UK energy market
1.2.1 UK energy market context
1.2.2 Competition, choice and home heating
1.3 Energy efficiency
1.4 State of the housing stock
1.5 Building regulations
1.6 Policies promoting domestic energy efficiency
1.7 Carbon emissions reduction target
1.8 Energy company obligation
1.9 Green homes grant voucher scheme
1.10 Heat technology choice
1.11 Heat pumps versus gas boilers
1.12 Policies promoting domestic low carbon heat technology adoption
1.13 Green deal
1.14 Renewable heat incentive
1.15 Boiler Upgrade Scheme
1.16 Outlook
1.17 Methodology and method design
1.18 Data analysis to estimate Boiler Upgrade Scheme-eligibility and heat pump-readiness
1.18.1 Estimating the proportion of homes that are Boiler-Upgrade Scheme-eligible
1.19 Estimating the proportion of homes that are heat pump-ready
Heat pump-ready | Not heat pump-ready |
---|---|
Well insulated, air sealed and draught-proofed to mitigate heat loss For example: with cavity wall insulation or exterior wall insulation and loft insulation (with low/good U-values) | Poorly insulated, air sealed and draught proofed For example: Solid walls with no insulation and stone/concrete floors and no heat loss mitigation. Cavity walls with no or partial insulation and stone/concrete floors and no heat loss mitigation, e.g. through draught proofing |
Good dispersal of heat through building: For example: underfloor heating, fan (forced draught) convector heating, high output low temperature radiators | Poor dispersal of heat through building: For example: traditional pipework and radiators, especially if performance has reduced over time |
Double or triple glazed windows (with low U-Values) | Single glazed windows (with high U-Values) |
System design and pipework sizing suitable for heat pump use. Newer systems are often ‘over-sized’ on installation and can deliver adequate heat when a boiler is replaced with a heat pump | Needs exceed the capacity of existing system and pipework |
1.20 Semi-structured interviews with Senior Managers in heat pump installation companies
Table 2 List of interviewees |
Company number | Seniority of interviewee | Company employees (FTE) | Region | Focus |
---|---|---|---|---|
1 | Director | 1 | Greater Southampton area | Heat pump installations |
2 | General Manager | 27 | Yorkshire and Humberside | Heat pump installations |
3 | Managing Director | 4 | Southwest England | Heat pump, air conditioning, solar PV installations |
4 | Managing Director | 35 | East of England | Heat pump and solar PV installations |
5 | Technical Director, Designer and Installer | 3 | Yorkshire and Humberside | Heat pump installations |
6 | Senior Consultant | 21 | Surrey | Consultancy on decarbonisation projects, including heat pump installations |
7 | Head of Air Source Heat Pumps | 16 | UK-wide | Heat pump installations |
8 | Director | 19 | Yorkshire and Humberside | Heat pump and solar PV installations |
9 | Business Leader / Co-founder | 65 | Gloucestershire | Heat pump installations |
10 | Managing Director | 9 | Greater Southampton area | Heat pump installer, EV charger installations |
11 | Director | 4 | Norfolk and Cornwall | Heating and plumbing, specialising in renewables installations |
12 | Director | 2 | Lincolnshire | Heat pump installations |
1.21 A nationally representative public opinion survey on heat pump adoption and readiness
1.22 Results and analysis
1.22.1 Boiler upgrade scheme eligibility and heat pump-readiness
1.23 Estimating boiler upgrade scheme eligibility
Table 3 Percentage of private housing stock estimated to meet the Boiler Upgrade Scheme criteria for insulation (Analysis of data from English Housing Survey 2021 to 2022: headline report) |
Total | |
---|---|
Cavity wall insulated | 9,337,000 |
Solid wall insulated | 535,000 |
Total insulated | 9,872,000 |
Total stock | 19,780,000 |
Percentage of private housing stock estimated to meet the Boiler Upgrade Scheme criteria for insulation | 49.9% |
1.23.1 Estimating heat pump-readiness
Table 4 Estimates of heat pump-readiness in England in terms of technical readiness and market readiness (Analysis of data from Energy Performance Certificate data) |
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Table 5 Cost of retrofit measures adapted from Palmer et al. 2017 and updated to reflect inflation |
Retrofit measure | 2022 inflation adjusted unit costs - mean value taken from range [125] | 2022 inflation adjusted total cost (small semi-detached home (less than 80m2)) - mean value taken from range [125] | 2022 total cost estimates (semi-detached 3 or 4 bedroom home) - online prices [125] |
---|---|---|---|
Cavity Wall Insulation [126] | £7 per square metre of wall | £671 | £750—£1000 |
Solid Wall Insulation [126] | |||
Internal wall insulation | £115 per square metre of wall | £8,869 | £5000 - £7000 |
External wall insulation | £139 per square metre of wall | £9,419 | £8500—£15,000 |
Loft insulation [126] | |||
Insulation installed at the joists | £18 per square metre | £465 | £550—£750 |
Insulation at the rafters | £35 per square metre | £2,590 | n/a |
Draught-proofing | £9 for 6 square metre of window film | n/a | n/a |
£11 for 10 m of door or window seal | n/a | n/a | |
£15 for a letterbox draught excluder | n/a | ||
New radiators and pipework [127] | £300 per radiator (scope to be higher or lower depending on choice / existing radiator sizing) | ||
Double or triple glazed windows [128] | n/a | £6,947 | UPVC: £3,000—£5,000 Hardwood: £5,000—£6,000 |
Figures rounded to nearest £ |
1.24 Summary
1.25 Semi-structured interviews with heat pump installation companies
1.26 Perspectives on the readiness of the housing stock for heat pumps and cost implications
Fig. 2 Estimated costs to make Home A and B heat pump-ready according to heat pump installation companies |
1.27 Perspectives on approaches to meeting market needs
Fig. 3 Themes from the content analysis of heat pump installer views on meeting market needs |
1.28 Perspectives on appropriateness of government action
Fig. 4 outlines the headline answers and themes derived from installation companies views on the Government’s action to support the market |
1.29 Summary
1.30 A nationally representative public opinion survey on heat pump adoption and readiness
1.31 Likeliness (intention) to transition to lower carbon heating
Table 6 How likely are you to upgrade your home to run on a lower-carbon heating system in the next 5 years? (e.g. using a heat pump to heat your home) |
n | % | |
---|---|---|
Likely | 219 | 22% |
Neutral | 185 | 18% |
Unlikely | 519 | 50% |
Don’t know | 107 | 10% |
1.32 Awareness of home improvements needed for the transition
Table 7 Do you have an understanding of the types of work that may be required to make your house heat pump-ready? |
N | % | |
---|---|---|
Higher awareness | 110 | 11% |
Low or no awareness | 774 | 89% |
Table 8 Do you (think you) meet the Boiler Upgrade Scheme’s eligibility criteria? |
N | % | |
---|---|---|
Likely | 359 | 35% |
Neutral | 154 | 15% |
Unlikely | 316 | 31% |
Don’t know | 202 | 20% |
1.33 Willingness to spend on the transition
Table 9 Please select the home improvements you would NOT be willing to consider or implement |
n | % | |
---|---|---|
Installing underfloor heating | 434 | 42% |
Replacing heating pipework | 290 | 28% |
Floor insulation | 263 | 26% |
Replacing radiators | 244 | 24% |
Cavity Wall Insulation or Solid Wall Insulation | 189 | 18% |
Installing a smart meter | 184 | 18% |
Double or triple glazing | 129 | 13% |
Loft insulation | 119 | 12% |
Air sealing / draught proofing | 118 | 11% |
None of these / I will consider making all improvements | 379 | 37% |
Table 10 What is the maximum cost you would be willing to incur to ensure your home is heat pump-ready? |
N | % | |
---|---|---|
I wouldn’t - it is not a priority unless it is fully funded by Government | 585 | 57% |
< £1,000 | 181 | 18% |
< £3,000 | 148 | 14% |
< £5,000 | 81 | 8% |
< £10,000 | 30 | 3% |
< £20,000 | 5 | 1% |
1.34 Concern factors regarding the transition
Table 11 How concerned are you about the following aspects of transitioning to a lower-carbon heating system? |
Upfront costs | Future energy bills | Disruption | Warmth worry | |||||
---|---|---|---|---|---|---|---|---|
n | % | n | % | n | % | n | % | |
More concerned | 717 | 70% | 301 | 52% | 495 | 48% | 399 | 39% |
Less concerned | 312 | 30% | 280 | 48% | 535 | 52% | 631 | 61% |