Guide
Commercial solar feasibility study UK
A commercial solar feasibility study tests whether a rooftop is worth pursuing before you spend on surveys, installer visits, or detailed design. This guide explains what it covers, who needs one, and how Stage1Energy delivers a fixed-fee, fully sourced report.
What a commercial solar feasibility study is
A commercial solar feasibility study is an early-stage, remote, evidence-based assessment of whether rooftop photovoltaic (PV) is worth pursuing on a specific UK commercial building. It answers four questions in writing: how much the roof could generate, what the financial return looks like over 25 years, whether obvious engineering or regulatory barriers exist, and whether the project is worth taking to the next stage.
In one sentence
It is a decision document that ends in pursue, pursue with conditions, or park — readable by a board, landlord, or asset manager without specialist solar knowledge.
It is not detailed design, structural certification, or an installer quote. It sits upstream of those steps. A structural roof loading report tells you whether a roof will hold the system you have already decided to buy. This tells you whether to buy anything, and at what size.
Register interest via the waiting list. We open capacity in order.
Process
How the process works
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Brief the site
Address, roof type, and consumption data (half-hourly preferred). No site visit required to start.
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Yield and finance
Feasibility-grade generation, self-consumption, and a 25-year financial case with named assumptions.
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Engineering screen
Wind, structure, DNO (G98/G99), and planning — each with a clear next step if confirmation is needed.
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Board-ready report
Pursue, pursue with conditions, or park — with every material figure traced to its source.
Who orders a feasibility study
Commercial solar feasibility studies are commissioned by landlords screening a portfolio, estates teams evaluating a single asset, property developers testing a scheme before acquisition, and advisers who need an independent number their client can rely on.
- Commercial landlords
Rank roofs across a portfolio before committing survey spend.
- Estates and facilities
Build an internal business case for capex approval.
- Developers and investors
Test whether solar improves IRR on a building before purchase.
- Consultants and advisers
Obtain a sourced report to support client recommendations.
See building-type guides for warehouses, landlord portfolios, and commercial rooftops more broadly.
What is in the report
Every Stage1Energy feasibility report contains the same sections whether you book one roof or thirty:
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Written verdict
Pursue, pursue with conditions, or park — with system size, annual yield, NPV, and named next steps stated plainly.
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25-year financial case
Capex build-up, payback, IRR, NPV, and hour-by-hour cashflow.
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Zone-by-zone roof layout
Panel placement on satellite imagery with setbacks and exclusions.
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Four engineering flags
Wind, structure, DNO (G98/G99), and planning permitted development.
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Sourced workings
Formula, result, and reference for every material figure.
Read the full structure in the example report or our guide on what is in a feasibility report.
Independent study vs installer quote
Feasibility study
Should we pursue this roof?
- Paid the same for pursue or park
- Shows workings you can challenge
- Screens structure, grid, and planning
- Board-ready independent verdict
Installer quote
What will you sell us?
- Income depends on a proceed decision
- Useful once you have decided to go ahead
- Prices kit and labour, not the investment case
- Weak basis for the decision itself
Installer visits, drone surveys, and structural appointments typically cost hundreds or thousands per site before anyone has tested the headline numbers. A feasibility study front-loads that test for a fixed fee. Read the full comparison in feasibility study vs installer quote, or validate an installer quote you already hold.
Cost and turnaround
Key numbers
Written terms before paid work. Capacity opens via the waiting list.
- Assessments Waiting list
- Standard delivery (once open) 5 days
- Priority delivery (when booking opens) By arrangement
- Portfolio programmes from 20 sites Per programme
Key numbers
Fixed fees with written terms — not an open-ended day rate.
- First building — full assessment Free
- First paid site (5 working days) £2,250
- Priority delivery (1–5 sites, 2 working days) +£750
- Portfolio programmes from 20 sites Per programme
See the waiting list page or feasibility study cost in the UK.
Methodology and limits
Every report is independent, human-reviewed, and prepared to a documented standard. Built from satellite and metered data. Compared against twelve months of metered output from operating commercial rooftop PV.
What this is not
Stage1Energy is a feasibility screening, not a precision measurement. Generation is modelled at P50 with a site-specific P90. CAPEX is quoted as a band. Structural and wind outputs are screening flags requiring verification by appropriately qualified professionals.
Our approach: methodology page.
Questions
FAQ
How is a commercial solar feasibility study different from a site survey?
A feasibility study is remote and evidence-based — no site visit required to start. It uses satellite imagery, consumption data you provide, and named, published sources. A site survey confirms conditions on the roof; feasibility is the earlier stage that tells you whether the survey is worth commissioning.
How long does a commercial solar feasibility study take?
Assessments open via the waiting list. Once capacity is available, standard single-site delivery is five working days from confirmed inputs. Priority timing is agreed when booking opens.
Can I get a feasibility study on multiple buildings?
Yes. Portfolio programmes start at 20 sites and run in tranches. Every building gets the same full report, plus a cross-portfolio ranking. Register interest on the waiting list — rates and sequencing are agreed in writing before paid work starts.
What if the report does not answer my question?
You will get a clear written recommendation — pursue, pursue with conditions, or park — with evidence and named next steps to defend it. If a delivered report does not give you that, we rework it at no additional cost.