Sources
Where our facts and figures come from
Every page lists its sources at the foot. Here they all are in one place, grouped, with what each supports and the date we last read it.
In brief
Welsh sources for Welsh rules: the Nest annual report and gov.wales guidance. UK sources for UK-wide schemes: GOV.UK, Ofgem, HMRC, legislation.gov.uk. Local figures from Census 2021 (Nomis) and PVGIS. The House of Commons Library for summaries, marked where used.
Checked at source on 3 November 2026 · An independent guide from SEO-DONS LTD, not the Welsh Government, Nest or a council
Welsh Government
The Welsh scheme and Welsh rules.
- Warm Homes Nest scheme annual report 2024 to 2025 (Welsh Government). Nest’s eligibility routes, health conditions, what it installs, the crisis route, the £35,000 threshold, spend by area, and modelled savings by local authority. Read 3 November 2026.
- planning permission for heat pumps (Welsh Government). Welsh permitted development for heat pumps from 1 June 2026. Read 3 November 2026.
- WSI 2026/79, heat pump permitted development in Wales (legislation.gov.uk). The 2026 Welsh amendment order for heat pumps. Read 2 November 2026.
- building work: competent person schemes (Welsh Government). Competent person schemes and self-certification under Welsh building regulations. Read 3 November 2026.
Local figures
The data behind the council-area pages.
- Census 2021 TS046, central heating, by local authority (Nomis). Households and central heating type for the six North Wales local authorities and for Wales. Read 3 November 2026.
- PVGIS solar estimates (SARAH3, 2005 to 2023) (EU Joint Research Centre). Yearly solar output per kWp near each administrative town. Read 3 November 2026.
- find your network operator (Energy Networks Association). Confirming the network operator for an address. Read 3 November 2026.
UK-wide schemes and rules
What applies across Wales from Westminster, Ofgem and HMRC.
- Apply for Warm Homes: Local Grant (England only) (GOV.UK). Warm Homes: Local Grant, for England only. Read 2 November 2026.
- Boiler Upgrade Scheme: what you can get (GOV.UK). Boiler Upgrade Scheme amounts and eligibility. Read 3 November 2026.
- SI 2026/390, Boiler Upgrade Scheme amendments (legislation.gov.uk). Removal of the EPC requirement and other 2026 changes. Read 2 November 2026.
- Warm Homes Loan Scheme factsheet (27 October 2026) (GOV.UK). The Warm Homes Loan Scheme as UK-wide for owner-occupied homes. Read 3 November 2026.
- Warm Homes Loan Scheme rules, version 3, September 2026 (PDF) (DESNZ). Loan scheme rules, including MCS certification for each measure. Read 3 November 2026.
- VAT Notice 708/6, energy-saving materials (HMRC). 0% VAT on installed energy-saving materials in homes to 31 March 2027. Read 3 November 2026.
- SEG guidance for generators (PDF) (Ofgem). Export payment rules: metering, MCS certification, Great Britain. Read 2 November 2026.
- Energy Company Obligation (ECO) (Ofgem). ECO4 and who administers it. Read 2 November 2026.
- Extending the ECO4 end date: government response (GOV.UK). ECO4’s end date and the purpose of the extension. Read 2 November 2026.
- The Warm Homes Plan (January 2026) (GOV.UK). The Warm Homes Plan. Read 3 November 2026.
- briefing CBP-9585 on home energy support (PDF) (House of Commons Library). Summary of ECO4’s position, used where noted. Read 2 November 2026.
- Find an energy certificate (England and Wales) (GOV.UK). Looking up an energy certificate in England and Wales. Read 3 November 2026.
- solar panels and planning permission (Planning Portal). Permitted development for solar on homes. Read 3 November 2026.
- find a certified installer (MCS). Checking an installer’s certification. Read 3 November 2026.
Protection
Advertising rules and consumer law.
- ruling on ECO4U Ltd (ECO4 adverts styled as government), December 2024 (ASA). ECO4 adverts presented as if run by GOV.UK. Read 2 November 2026.
- "Greener homes: building on facts, not fibs" (ASA). ASA guidance on home energy advertising. Read 2 November 2026.
- DMCC Act 2024, Schedule 20 (banned practices) (legislation.gov.uk). Practices banned outright since 6 April 2025. Read 2 November 2026.
- scams (Citizens Advice). Help with scams and disputes. Read 3 November 2026.
- SEO-DONS LTD (16766013) (Companies House). SEO-DONS LTD’s company record. Read 30 October 2026.
How the local figures were made
Census heating shares are the published percentages of households by central heating type for each local authority. PVGIS figures were requested for a 1 kWp south-facing system at 35°, with 14% losses and the local horizon, at each council's administrative town: Llangefni, Caernarfon, Conwy, Ruthin, Mold and Wrexham. Nest's savings are the Welsh Government's modelled averages by local authority for October 2024 to March 2025. We present them as published and don't adjust them. If a source updates, we update the pages and the dates. Tell us if you spot a newer version.
Not sure which scheme, if any, fits your home?
Tell us which council area you're in and what you're looking into. Your message reaches SEO-DONS LTD, the publisher of this guide, and we answer by email. We're not a scheme and can't approve anything, but we can point you to the right one.
What happens next
- Your message reaches SEO-DONS LTD, which publishes this guide.
- We reply by email with the scheme page that fits, if there is one.
- Any application is between you and that scheme.