Every year brings a fresh wave of “is commercial solar still worth it?” articles. In 2026 the honest answer remains the same: it depends on the roof, the load, the lease, and the grid - which is precisely why feasibility exists.
The 2026 investment backdrop
- Electricity costWholesale prices have stabilised from crisis peaks, but many commercial consumers still face materially higher import tariffs than a decade ago. Self-consumption remains the economic engine.
- Net-zero pressureCorporate targets, supply-chain questionnaires, and green lease clauses push landlords and occupiers toward measurable decarbonisation.
- Hardware maturityModule and inverter supply is competitive; flat commercial roof practice is well understood. Capex benchmarks are more stable than early FIT-era years.
- HeadwindsGrid queues, export price softness, roof refurbishment backlogs, and shorter leases constrain what geometry alone would suggest.
Feasibility translates this backdrop into site-specific verdicts - not sector generalisations.
What changed for feasibility assumptions
When updating or commissioning reports in 2026, pay attention to:
- Import tariffsUse current contract or realistic renewal figures - not 2022 peaks or pre-2021 lows. Sensitivity tables matter more than point estimates.
- Export / SEGExport-heavy sites remain sensitive to modest rate changes. Document assumptions explicitly.
- Capex£/kWp may improve on large roofs, but scaffolding, DNO works, and membrane coordination still dominate complex sites. State whether VAT and grid costs are in or out.
- GridDNO capacity and G99 timelines increasingly bind before roof area. Screen grid before structural spend - see feasibility vs structural survey.
- PolicyBusiness cases should stand on self-consumption economics, not anticipated subsidy windfalls.
Stage1Energy documents assumptions following our published methodology. Review how accurate solar generation estimates are when briefing boards on yield uncertainty.
Who is ordering feasibility in 2026
- Industrial & logistics owner-occupiers
- Retail parks & mixed estates
- Developers & forward funders
- Consultants before installer engagement
- Portfolio programmes
Industrial and logistics with high daytime load remain the sweet spot when grid allows. Retail and mixed estates balance landlord/tenant splits and roof condition. Developers testing solar on spec units need honest load bands. Consultants need independence before quotes - see feasibility study vs installer quote. Portfolio programmes use portfolio solar feasibility screening.
A sensible 2026 process
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Internal mandate
Agree net-zero or cost-saving mandate and capital envelope.
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Filter the estate
Eligibility, coarse fit, waiting list where useful.
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Independent feasibility
Comparable assumptions across shortlisted sites.
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Approve next spend
Confirmatory surveys on positives, then tender and install.
When to order a solar feasibility study still applies: after you have a credible site, before heavy survey spend.
Cost and capacity planning in 2026
Stage1Energy in 2026
- Standard delivery per siteWaiting list
- Priority surcharge (1–5 sites)+£750
- Early filteringFree screen
See solar feasibility study cost in the UK. Budget feasibility as a line item in annual property programmes - one wave in Q2 for autumn board cycles is a common rhythm.
What boards should expect in 2026 papers
Directors need
Independent feasibility (not installer marketing), explicit grid and lease risks, sensitivity on tariff and self-consumption, and staged approval asks. Use solar investment board paper structure and attach full reports as evidence.
Looking ahead without guessing policy
Looking ahead
Build cases on self-consumption
Feasibility in 2026 should not depend on speculative subsidy announcements. Document export exposure and note reassessment triggers - lease renewal, roof works, tariff renegotiation, local grid reinforcement. Sites marginal today may clear tomorrow; strong sites should not wait for perfect policy clarity.
Start on your estate
Generic market optimism wastes budget. Site-specific feasibility preserves it.
Begin at commercial solar feasibility, submit priority addresses for waiting list, and advance winners to site assessment. 2026 rewards estates teams who rank roofs with evidence - not those who install on enthusiasm alone.
Working with consultants and managing agents
If you commission on behalf of landlord clients, agree upfront who holds the report, who presents to the board, and who orders confirmatory surveys. Independent site assessment terms simplify pass-through billing compared with day-rate advisory that expands in scope. Combine Stage1Energy reports with your own cover note on portfolio strategy - the PDF supplies technical independence; you supply relationship context.