Commercial solar companies — how to pick the right one for your project.

The three categories of UK commercial solar company

1. MCS-certified commercial installers (~200 firms)

The companies that physically design, procure, install and commission your solar PV system. They hold MCS commercial certification (MCS 020 and equivalents), NICEIC or equivalent electrical certification, and are members of an MCS-aligned scheme that issues Insurance-Backed Warranties. The UK market splits roughly into:

• Regional electrical contractors with solar specialism — typically projects under 250kWp. Strength: local knowledge, relationships with regional DNO. Weakness: smaller engineering teams, limited capability for large-scale or complex projects.
• Dedicated commercial solar EPCs — 200kWp-5MWp range. Most active firms in the UK commercial market. Examples include Custom Solar, Mypower UK, SolarSense, Shawton Energy, Spirit Energy, Custom Solar.
• Specialist large-scale developers — 1MWp+ projects, often paired with PPA funders. Examples include Atrato Solar, Statkraft, Lightsource bp.

An installer's revenue model is structural: they get paid for the system they install. That creates an incentive to maximise system size and capex. We have audited installer quotes that filled 100% of available roof area on the basis "more solar = more savings", when self-consumption modelling showed the right system was 60% of that capacity.

2. Independent funding consultants (~20-30 firms)

Specialist firms that source the right funding stack — grant, tax, PPA, asset finance — and project-manage delivery. We are one. Funding consultants typically don't sell solar panels. Revenue comes from grant applications and project management on grant-funded builds, which means the right system for the client and the right system for our P&L are the same.

Specifically, an independent funding consultant typically:

• Pulls half-hourly meter data and builds a financial model against actual demand profile
• Models grant + tax + PPA routes side by side, showing net economics for each
• Walks clients away from projects that don't pay back (about a third of our scopes)
• Drafts grant applications where appropriate (REPF, Local Growth Fund, Salix, SIETF)
• Project-manages the build through MCS-certified delivery partners
• Does not take installer commissions

For projects of £150k+, an independent funding consultant typically pays for themselves several times over by getting the right system size and the right funding stack. More on how we work.

3. PPA funders (~15-20 active UK firms)

Specialist solar investors that fund commercial PV under Power Purchase Agreement structures. The funder pays for and owns the asset; the site host signs a 15-25 year contract to buy the electricity at a fixed pence/kWh, typically 6-9p/kWh below grid prices. Major UK PPA funders in 2026 include Atrato, NextEnergy Capital, Octopus Energy Generation, Foresight Group, Greencoat Capital UK, Bluefield Solar, JLL Ardent. Tariff economics vary 0.5-1.0p/kWh between funders — competitive tendering pays. Full PPA guide.

How to pick the right combination for your project

Project under £100k (small SME, sub-100kWp)

Direct engagement with an MCS-certified regional installer is usually fine. The transaction cost of involving a funding consultant rarely makes sense at this scale. Confirm Full Expensing applied (or AIA for non-companies), 0% VAT, MCS commercial certification, and IBW. Our free quote-benchmarking covers this if you want a sense check.

Project £100k-£500k (mid SME, 100-500kWp)

The sweet spot for funding consultancy. Multiple grant + tax routes typically apply, the financial modelling materially affects the net cost, and the engagement fees easily pay back. Engagement model: we scope, model, advise on funding stack, recommend installer match, project-manage the build.

Project £500k-£3m (large SME, mid-corporate, 500kWp-3MWp)

Funding consultancy + competitive installer tendering + PPA evaluation. Multiple PPA funders should be solicited (we typically get 2-4 quotes per project at this scale). Tariff differences of 0.5p/kWh compound to £200k+ over 25 years.

Project £3m+ (major industrial, large NHS, large MAT)

Strategic engagement. Multiple workstreams in parallel: financial modelling, grant/loan application (Salix BAU loan or Local Growth Fund), procurement framework selection, EPC tender, structural and DNO surveys. Project management is the dominant cost line. We have run £6m+ projects through this model.

Red flags in commercial solar company quotes

1. "Civils" line that hides costs. Always demand a separate DNO line.
2. No structural engineer's report on pre-2000 buildings. Adds ~£18k of bracing cost typically — should be quoted up front.
3. Generic "fill the roof" sizing. Real sizing is done off half-hourly meter data, not roof dimensions.
4. 20% VAT default on commercial. 0% VAT applies — always ask.
5. No IBW line. Either the installer isn't MCS-aligned (avoid) or the warranty cost is buried (still avoid).
6. "Battery storage" without sizing analysis. Battery sizing should be calculated from your actual self-consumption and demand profile, not a generic ratio.
7. Yield projections >2% above PVsyst-equivalent for your latitude. Some installers inflate yield to make payback look better.
8. No reference to MCS commercial certificate transfer. The MCS certificate must be in your business name to claim SEG. Confirm at quote stage.

Where we sit in the market

We are an independent funding consultancy, not an installer. We don't sell solar panels. Our revenue comes from grant applications and project management on grant-funded builds. We project-manage installations through six MCS-certified delivery partners across the UK (covering UKPN, NGED, NPG, ENWL, SPEN and SSEN territories), selected by region and project type. Our 5-step process. More about how we work.