The measures, side by side
| Measure | Capex | Annual saving | Payback | EPC points | Disruption | Grade |
|---|---|---|---|---|---|---|
| Solar PV | £400k | £96k | 4.2 yr | +10 pts | Low | A |
| LED relighting | £75k | £12k | 6.3 yr | +5 pts | Low | B |
| HVAC controls | £45k | £8k | 5.6 yr | +3 pts | Low | B- |
| Fabric upgrades | £850k | £14k | 60 yr* | +12 pts | High | D |
| Heat pump retrofit | £480k | £22k | 22 yr | +14 pts | High | B+ |
*Payback beyond 25 years means measure doesn't pay back in cash terms — value is in MEES compliance, EPC uplift, or operational benefit.
Why solar PV wins on cash payback
Of the five MEES-eligible measures, solar PV is the only one where the avoided electricity cost (savings) exceeds the depreciation cost (capex over asset life). The numbers are stark: a £400k solar install on a 5,000 sqm office saves £96k/year in avoided grid electricity at 30p/kWh; capex is recovered in 4.2 years. By contrast, fabric upgrades cost £850k and save £14k/year (60-year payback in cash terms; never economic).
This doesn't mean fabric and heat-pump retrofits are wrong investments — they're MEES compliance investments. They lift EPC points and keep the building lettable. But landlord boards reviewing capex requests need to understand the distinction: solar is a savings investment that also delivers compliance; fabric and heat-pump are compliance investments that also reduce energy use.
The recommended stack for C → B uplift
For a 5,000 sqm office currently rated EPC C (typical SAP score 65-70), the recommended MEES 2030 compliance pathway combines two measures:
1. Solar PV
£400k capex, £96k/year saving, 4.2yr payback. AIA-eligible.
2. LED relighting + controls
£90k capex (including controls), £14k/year saving, 6.4yr payback.
Combined
£490k combined capex, £110k/year saving, 4.5yr blended payback. EPC C (65) → B (81).
The combined approach future-proofs the building against any post-2030 tightening of MEES (under consultation toward EPC A by 2035) and locks in the strongest tenant proposition.
For D → B uplift (more challenging)
Buildings starting at EPC D (typical SAP score 55-64) need 16-26 SAP points to clear EPC B. The three-measure stack typically works:
- Solar PV (+10 pts)
- LED + controls (+6 pts)
- Heat pump retrofit OR fabric upgrade (+8-14 pts) — choice depends on existing heating system and fabric condition
For gas-heated buildings, heat pump retrofit typically wins on points-per-capex. For electric-heated buildings, fabric upgrades take precedence.
What this means for portfolio capex planning
For office portfolio managers approaching MEES 2030, the practical sequencing in 2026-2028 looks like:
- Audit every EPC — particularly pre-2022-issued Bs (high re-rating risk under SAP 10.2)
- Commission solar feasibility on every flat-roof office above 2,000 sqm — most will deliver MEES compliance and positive NPV simultaneously
- Sequence capex by deadline urgency — buildings facing 2027 EPC C deadline first, then 2030 EPC B
- Layer additional measures on buildings where solar alone won't clear the threshold — LED first (lowest disruption), heat pump or fabric only where required
- Document MEES exemption applications where measures genuinely can't be deployed — listed buildings with no compliant route, third-party consent denials, devaluation cases