What boards actually want to see
Office solar proposals fail at board level more often through poor business case framing than through bad project economics. After supporting 40+ commercial solar capex papers through to board approval, four framing elements consistently determine outcomes.
1. NPV over 25 years, not simple payback
Simple payback (capex / annual saving) is a finance director’s first metric but rarely the deciding one. Boards comparing solar capex against other investments want NPV at the company’s WACC, IRR, and a risk-adjusted ROI.
Typical UK office solar at 5-6 year payback delivers 25-year NPV of 5-7× the capex outlay at 7-10% WACC. That framing — “for every £1 we invest, we get back £6 over 25 years discounted to present value” — is more compelling than “5 year payback.”
2. Cash-flow profile, not just headline returns
Boards considering capex want to understand cash-flow shape over time. For solar:
- Year 0: capex outflow
- Year 1: AIA tax saving (25% of capex for limited companies)
- Years 1-25: annual savings flow (££/year)
- Year 12-15: inverter replacement (£35-60/kW)
- Year 25-30: panel performance below economic threshold
The cash-flow profile is unusual among capex investments because of the large year-one tax benefit (AIA) and the very long tail of positive cash flows.
3. Risk-adjusted decision framing
Solar PV has lower technical risk than most major capex investments — it’s well-understood technology with 30-year operating histories. But boards want to understand specific risks:
- Grid price risk. What if electricity prices fall? Below ~18p/kWh blended retail, project NPV starts to degrade.
- Self-consumption risk. What if building occupancy patterns change (more hybrid working, building disposal)? Self-consumption falls but SEG revenue rises partially compensating.
- MEES compliance risk. What if EPC re-rating doesn’t deliver predicted uplift? Typically captures 60-90% of modelled gain even in adverse cases.
- Tenant change risk (for landlord installs). What if a major tenant departs? Service-charge recovery proportion may fall.
- Technology obsolescence risk. What if panels become dramatically cheaper in 10 years? The installed system continues delivering its modelled value; new technology doesn’t make existing systems worse.
4. Strategic ESG framing
Boards approving solar capex are increasingly looking at it as a multi-factor decision: financial return + ESG positioning + MEES regulatory compliance + tenant proposition + employer brand. The financial case stands on its own merit, but the strategic case multiplies it.
For multi-let landlords specifically, the MEES 2030 framing is now the dominant driver: “this is mandatory regulatory compliance with a positive NPV” is a much stronger board proposition than “this is voluntary capex with positive NPV.”
The 6-page template
A workable board paper structure that consistently wins approval:
Page 1: Executive summary (1 page)
- Investment ask (£)
- Financial summary (NPV, IRR, payback, year-one cash impact)
- Strategic rationale (1 paragraph)
- Recommendation (specific board decision required)
Page 2: Project overview (1 page)
- System specification (kWp, panels, inverters, battery)
- Site description
- Programme (key dates, dependencies)
- Technical risk summary
Page 3-4: Financial analysis (2 pages)
- Capex breakdown
- Annual cash flow projection (25 years)
- NPV at WACC sensitivity
- IRR
- Comparison with alternative capex priorities
- Funding route recommendation
Page 5: Strategic and risk (1 page)
- ESG positioning impact (Scope 2 reduction, SECR/TCFD/CDP)
- MEES 2030 compliance positioning
- Tenant proposition impact (multi-let) or recruitment impact (single-occupier)
- Key risks and mitigations
- Sensitivity to electricity price assumptions
Page 6: Decision and next steps (1 page)
- Specific board decision required
- Approvals required (sub-committee, audit, environmental)
- Programme to commissioning
- Reporting cadence
What we provide
For every office solar proposal, we provide:
- Board-paper-ready executive summary text
- 25-year cash flow projection (Excel + summary table)
- NPV at user-defined WACC
- All four funding route comparisons
- ESG documentation pack draft
- Risk register
- Programme
The materials are designed to drop into a board paper with minimal additional work — typically saving 20-40 hours of finance team time.
Request a feasibility study with board-paper-ready materials.
Executive summary template: the one-page version that works
The first page of a solar capex paper is the only page most board members will read in full. It must contain all the information needed for a decision and none of the information that invites scope creep or objections.
A template that consistently delivers approval:
CAPITAL INVESTMENT PROPOSAL: SOLAR PV SYSTEM — [BUILDING NAME]
Investment amount: [X] (excluding VAT; net of AIA: [Y]) Funding route: [Cash purchase / Asset finance / PPA] Recommendation: Approve capital commitment and authorise procurement to proceed
Financial summary:
- Simple payback: [X] years
- 25-year NPV at [WACC]% WACC: [Y]
- IRR (unlevered): [Z]%
- Year 1 AIA tax saving: [A] (effective net capex: [B])
- Annual electricity saving (Year 1): [C]/year
- Annual CO2 reduction: [D] tonnes CO2e (location-based Scope 2)
Strategic rationale: [One paragraph covering: MEES 2030 compliance position, ESG/SECR/CDP benefit, tenant proposition, employer brand. Maximum 80 words.]
Key risks: Planning approval risk [Low/Medium/High]; Grid connection timeline [X months]; Electricity price sensitivity [payback remains sub-[N] years at [P]p/kWh].
Board decision required: Approval of capital expenditure of [X] and authority to enter into contracts with [installer name].
This format takes a typical finance team 20-30 minutes to populate from the installer’s proposal materials rather than hours. Every metric on this page comes directly from the PVSyst model, the cash flow projection, and the installer’s documentation pack.
Financial model structure: what the 25-year projection should include
A properly-structured 25-year financial model for an office solar project has five components:
Component 1: Annual generation schedule. Year-by-year PV generation (kWh) reflecting the PVSyst Year 1 yield and applying the warranted degradation rate (typically 0.5-0.8% per year for n-type TOPCon panels, 0.6-1.0% for p-type PERC). Generation in year 25 is typically 85-92% of Year 1 generation depending on degradation assumption.
Component 2: Self-consumption and export split. Year-by-year self-consumption and export volumes. Self-consumption may increase slightly over time if EV charging or battery storage is added; may decrease if the building is partially vacated. The base case holds the Year 1 self-consumption ratio constant.
Component 3: Revenue and savings. Annual electricity saving (self-consumed kWh x avoided grid tariff, escalated at assumed annual rate, typically 3% real). Annual SEG revenue (exported kWh x assumed tariff, held flat in real terms for conservatism). AIA tax saving (year 1 only). Year 12-15 inverter replacement cost (negative cash flow).
Component 4: NPV calculation. Discount all cash flows at the company’s WACC. Sensitivity analysis at WACC +/- 2% and electricity price +/- 20%.
Component 5: IRR calculation. Internal rate of return on the after-AIA capex. Most commercial solar projects at current prices deliver 14-19% IRR. The comparison hurdle rate is the company’s WACC or a pre-agreed capex hurdle rate.
A well-structured model typically fits on two A4 pages (one cash flow table, one sensitivity matrix) and is the most important tool in the board paper.
Risk register: the board expects to see this
A risk register for a commercial office solar board paper should cover seven items. Two are structural; five are operational.
Structural risks (present in all projects):
1. Planning refusal risk. Probability: Low for standard Permitted Development cases; Medium for Prior Approval on larger systems; High for Conservation Area or Listed Building settings. Mitigant: pre-application planning advice (PAPA) obtained; installer has heritage solar track record. Financial impact if materialises: project does not proceed; feasibility cost (typically 2,000-5,000) is the only sunk cost.
2. G99 network study requirement. Probability: Low in non-constrained network areas; Medium to High in London UKPN and urban ENWL areas. Mitigant: pre-application DNO enquiry completed. Financial impact if materialises: additional engineering study cost (5,000-20,000) and programme extension (3-6 months). Does not typically affect project economics materially.
Operational risks (arise during project life):
3. Electricity price falling below 18p/kWh. Impact on NPV: moderate negative (project still positive but reduced returns). Probability over 25 years: Low based on current UK energy market outlook, carbon pricing trajectory, and network charge trends.
4. Self-consumption falling due to building occupancy change. Impact: proportional reduction in electricity savings; partial offset from higher export income. Probability: building-specific; higher for multi-let buildings with tenants on short leases. Mitigant: battery storage addition at year 3-5 can restore self-consumption if occupancy patterns change.
5. Inverter failure before warranty expiry. Impact: temporary generation loss; repair cost if outside warranty. Probability: 2-5% per inverter per year at 10-15 years. Mitigant: 10-20 year inverter warranty extension included; O&M contract with reactive response SLA.
6. Structural issue with mounting. Impact: system outage; repair cost. Probability: Very Low on modern MCS-certified ballasted installations with full structural engineering sign-off. Mitigant: BS EN 1991-certified structural design; workmanship warranty; IWA.
7. Installer insolvency. Impact: workmanship warranty becomes unenforceable. Probability: Low (established, financially sound installer). Mitigant: IWA from A-rated insurer (QANW) covers workmanship warranty continuation.
Presenting to the risk committee: the MEES regulatory risk angle
For commercial property companies and institutional investors, MEES 2030 reframes the solar investment decision from discretionary capex to regulatory risk mitigation. This framing consistently accelerates board approval in risk committee contexts.
The argument:
Position A: Invest in solar now. Capex: 500,000. NPV benefit: +2.1 million. MEES 2030 compliance: achieved. Rental arrears from empty substandard-rated space: 0. Fine or prohibition risk: 0.
Position B: Do not invest now. Capex: 0 saved. EPC remains at D. From April 2030, it becomes unlawful to let commercial property below EPC-B. If the building cannot be let, annual gross rental income lost: 800,000/year. To achieve EPC-B after 2030 under urgent compliance pressure (likely higher contractor prices, less negotiating leverage): cost estimate 500,000-700,000. NPV cost of non-compliance: highly negative.
The risk committee question becomes not “should we invest 500,000 in solar” but “do we prefer the risk of 500,000 solar investment with 2.1 million NPV, or the risk of unlettable assets and emergency compliance costs after 2030.” Framed this way, solar almost always wins at risk committee.
For this framing to work, the board paper must include:
- Current EPC rating for the relevant building
- Current MEES 2030 gap (is it currently above or below B?)
- Projected EPC after solar installation
- Quantified rental income at risk if EPC-B compliance is not achieved by 2030
This data is available from the EPC assessor and from the installer’s SBEM modelling output.
What we provide
For every office solar proposal, we provide:
- Board-paper-ready executive summary text in the template format above
- 25-year cash flow projection (Excel + summary table)
- NPV at user-defined WACC with sensitivity matrix
- All four funding route comparisons (cash, asset finance, operating lease, PPA)
- ESG documentation pack draft (SECR, TCFD, CDP, SBTi)
- Risk register in the format above
- Programme with Gantt chart
- MEES compliance impact assessment
The materials are designed to drop into a board paper with minimal additional work — typically saving 20-40 hours of finance team time.
Key takeaways
- The executive summary page is the board paper; all other pages are the appendix — invest in getting the one-pager right
- A 25-year financial model needs five components: generation schedule, self-consumption split, revenue/savings, NPV calculation, and IRR
- Seven risks appear in every well-structured risk register; two are structural (planning, G99), five are operational (price, self-consumption, inverter, mounting, installer)
- MEES 2030 reframes the risk register from voluntary investment to regulatory risk mitigation — use this framing for risk committee presentations
- We provide board-paper-ready materials including executive summary, financial model, risk register, programme, and ESG documentation