Blog · Published 2026-05-12

How to prepare a winning PSDS Phase 4 application for your school in 2026

Phase 4 of the Public Sector Decarbonisation Scheme is expected to open in 2026 with a similar budget to Phase 3c (~£230m). For state-maintained schools and many academies, PSDS is the most generous capital grant available — funding 100% of qualifying decarbonisation projects including solar PV, heat pumps, insulation, LED, and building management systems. The challenge is access: PSDS funding rounds are often committed within hours of opening, and only well-prepared applications make the cut.

Will my school qualify?

Eligible bodies typically include: - Local Authority-maintained primary and secondary schools (eligible) - LA-maintained nurseries (eligible) - Multi-academy trusts (variable — check current Salix guidance for your specific trust type) - Standalone academies (variable) - Sixth-form colleges and further education colleges (eligible — funded through ESFA) - Free schools (variable) - Voluntary aided / voluntary controlled schools (eligible if LA-maintained) - Foundation schools (variable) - Independent schools (NOT ELIGIBLE for PSDS — use AIA + SEG instead)

Always confirm with Salix Finance current guidance — academy eligibility rules change between phases.

Why PSDS prioritises integrated packages

PSDS scoring is heavily weighted towards heat decarbonisation — replacing gas or oil boilers with heat pumps. Solar PV scores points but typically as part of a wider package, not on its own. Strong PSDS applications combine:

- Heat pump replacement of fossil-fuel heating (typically the largest single capex item) - Insulation and fabric upgrade (often required to make heat pumps work) - Solar PV (offsets the higher electrical demand the heat pump creates) - LED lighting (small but high-impact carbon saving) - Building management system upgrade (verifies post-installation savings)

A well-integrated package typically delivers 50-70% carbon savings on the building. PSDS prefers ambition — packages targeting under 30% carbon saving rarely score well.

Application preparation timeline

Now (May 2026): pre-Phase 4 prep. If you haven't started, you're already behind. Strong applicants typically begin RIBA Stage 2 design 12-18 months before the funding window. Practical actions for this month: - Get an estate-wide carbon footprint completed (Carbon Trust or local-authority-recommended assessor) - Identify your top 3-5 priority buildings for decarbonisation - Engage a building services engineer for high-level design - Estimate total programme capex and PSDS grant request

6-9 months before window opens: RIBA Stage 3 design. Detailed engineering design ready for application.

3-4 months before: financial case. Cost plan to RICS standards, life-cycle assessment, post-installation maintenance plan.

1-2 months before: governance. Project sponsor sign-off, governing body approval, procurement strategy approval.

Window opens: submit within first 24-48 hours. Phases close fast. Be application-ready before the window opens.

Typical winning project sizes

Phase 3 awards averaged around £1.5m per project. The sweet spot was £500k-£2.5m — large enough to justify the application effort, small enough to deliver within the 18-month window.

Typical school-scale projects: - Single primary school: £150k-£400k (heat pump + insulation + solar + LED) - Single secondary school: £400k-£1.2m (larger scale of same package) - Multi-academy trust (5-10 schools): £1m-£3m programme bundle - Local authority (20+ schools): £3m-£15m portfolio rollout

Solar PV specifics

For the solar PV element specifically: - Typical primary school: 15-30 kWp - Typical secondary school: 50-150 kWp - FE college: 100-300 kWp - Per-school capex: £15k-£150k - Self-consumption assumption: 45-55% (school holidays drag the figure down) - Term-time self-consumption: 65-75% - SEG income during holiday periods is material — schools should size for this

The roof condition is often the binding constraint. Many UK primary schools have asbestos cement roofing dating from the 1960s-70s that needs replacement before solar — adding £30k-£100k to the project cost but extending the building life by 25+ years.

Post-award delivery

PSDS-funded projects must complete within 18 months of award. Tight delivery windows mean: - Procurement must run in parallel with award notification (e.g. framework call-offs) - Contractors must mobilise within 4-6 weeks of grant - Construction typically in school holidays (limited windows) - Commissioning, training and BMS handover within term breaks - First-year energy savings monitoring starts immediately on commissioning

Around 8% of Phase 3 awards had to repay grant for missed delivery milestones — driven mostly by procurement delays and contractor underperformance. Strong project management is non-negotiable.

FAQs

FAQs on this topic

Can my school apply for PSDS alone, or do we need a consultant?

Most schools use a specialist consultant for the application — typical fees £15k-£50k. Multi-academy trusts often use in-house estates teams supported by an external technical advisor. Small standalone schools can apply directly with a strong head/business manager and energy consultant support.

How much does the application cost in professional fees?

For a £1m project: typically £40k-£90k in professional services (energy auditor, building services engineer, grant writer, QS, technical advisor). For a £100k project: £15k-£30k. This is a real cost that some applicants miss — and it's often only partly recoverable from the grant.

Can PSDS fund solar PV only?

Standalone solar applications are very unlikely to win. PSDS prioritises heat decarbonisation. Solar must form part of a wider package.