Solar Carports for Commercial Property

If you own a commercial asset with a surface car park, that tarmac is generating nothing today. A solar carport — a steel canopy carrying solar panels over the parking bays — turns that footprint into a second generating roof, shelters tenants’ and visitors’ vehicles, and provides a natural mounting point for EV charging. For owners short on usable roof area, or whose roof is the wrong age or structure for solar, the car park is often the better asset to develop. This guide covers what a carport is, the planning route, where the value sits, how the cost compares to rooftop, and which assets are the strongest fit.

What a solar carport is

A solar carport is an elevated steel frame spanning rows of parking spaces, with solar panels forming the canopy roof. The structure is engineered to wind and snow loading, with clearance for vehicles beneath and a slope (or back-to-back pitch) that sheds water and directs runoff to gutters and downpipes. Panels connect through string inverters to the building’s supply or a dedicated meter, exactly as a rooftop system does.

The appeal is that the canopy does three jobs at once. It generates power on land that was producing nothing. It shelters parked vehicles from sun, hail and frost. And its underside and supporting columns are the obvious home for EV chargers, lighting and cable routing. Unlike a rooftop array — which is invisible and adds no day-to-day amenity — a carport is a visible upgrade that tenants, staff and customers experience directly.

Yield is comparable to a well-oriented roof: around 950 kWh per kWp per year in the UK, depending on the canopy’s pitch and orientation. As with any commercial array, the return is driven mostly by how much of that generation you consume on site rather than export. Daytime parking — offices, retail, leisure — tends to coincide well with solar output, which helps self-consumption.

The Class OA permitted-development right

Car-park solar canopies have their own permitted-development route in England. Class OA, introduced under the 2023 changes to the General Permitted Development Order, allows solar canopies over off-street parking on non-domestic land without a full planning application, within set limits. The headline conditions are:

• The canopy must be no more than 4 metres high.
• No part may be within 10 metres of the curtilage of a dwellinghouse.
• Prior approval is required for glare — you apply to the local planning authority for a determination on the design’s potential to dazzle drivers, neighbours or aircraft, plus siting and external appearance.

Class OA is a genuine right, not a free pass. Prior approval still means a formal submission and a determination period, and the authority can refuse on the matters reserved to it. Listed buildings, conservation areas, AONBs and similar designations carry extra constraints or remove the right. Treat Class OA as a faster, more certain route than full planning — but plan the glare assessment and a structural design early, and confirm the right applies to your specific site before committing. The wider planning and grid picture for commercial solar is covered in our planning and grid guide.

The other gate is the grid connection, not planning. Any array above roughly 50kW needs a G99 application to the local Distribution Network Operator, and the DNO’s response — whether the connection is accepted, capped or carries reinforcement costs — is usually the real determinant of system size and timeline. A canopy across a large car park can easily exceed that threshold, so make the DNO enquiry in parallel with the prior-approval submission.

Generation, EV amenity and tenant attraction

The strongest carport business cases stack three value streams rather than relying on generation alone.

Generation. The canopy produces power you can self-consume, displacing units bought from the grid at roughly 24–28p and cutting your or your tenants’ import. Export earns the Smart Export Guarantee — typically around 12–16p on the best fixed tariffs — so the economics favour consuming on site. Pairing the canopy with commercial battery storage lifts self-consumption further by shifting daytime surplus into evening or overnight demand.

EV charging. Carports are the natural host for workplace and destination charging. The columns and canopy provide structure, weather protection and a cable route, and daytime solar can feed AC chargers (typically 7–22kW) directly, soaking up generation that would otherwise be exported. DC rapid units (50kW and above) need their own grid capacity but pair well with a battery. The OZEV Workplace Charging Scheme exists for eligible businesses; check current eligibility and terms on gov.uk rather than relying on any quoted figure. Our commercial EV charging guide sets out how charging and solar combine on a site.

Tenant attraction and value. Sheltered parking with charging is a tangible amenity in a leasing pitch. For offices and retail, it differentiates the asset; for multi-let estates, it is a common-parts improvement the owner can fund and recover value from. It also feeds the asset’s ESG and energy story — useful for valuation, fund reporting and the green-lease conversation covered in our green premium guide.

A dedicated specialist runs the car-park canopy and charging discipline end to end — design, structure, glare assessment and charger integration. See solar car parks and canopies for that specialism.

Cost: how carports compare to rooftop

A carport costs more per kWp than a rooftop array because you are paying for a substantial steel structure as well as the solar system. A rooftop install uses the existing roof as the mounting surface; a carport has to build that surface from scratch, with foundations, columns, beams and the canopy frame all engineered to wind and snow loads.

As a rule of thumb, expect the structural premium to push the per-kWp figure meaningfully above the typical commercial rooftop range of about £700–1,100 per kWp, with the exact uplift depending on ground conditions, foundation type, span and finish. The payback is therefore longer than an equivalent rooftop system on generation alone — which is precisely why the EV-charging and amenity value matters: the canopy earns its keep across several streams, not one.

The tax treatment is the same as any commercial solar asset. Solar is special-rate plant, so the spend qualifies for 100% relief under the Annual Investment Allowance (the £1m permanent allowance) rather than full expensing, which gives only 50% first-year allowance on solar. The chargers and electrical works fall under the same regime. There is 0% VAT on the commercial install, and the equipment is exempt from business rates to 2035. The detail sits in our capital allowances and funding guide, and you can model a scheme through our cost page or request a site-specific quote.

Where the canopy serves let space rather than an owner-occupier, the split-incentive question applies — who funds the canopy and who captures the saving. Common-parts supply, a tenant PPA or a roof-lease structure all work over a car park as they do over a roof; see our split-incentive guide for the mechanisms.

Best-fit assets

Carports earn their structural premium where there is a large, well-used surface car park and a reason beyond generation to build.

• Retail parks and out-of-town retail. Big surface car parks, strong daytime occupancy that matches solar output, customer EV charging as a footfall and dwell-time draw, and a visible sustainability signal. Our retail property vertical covers the sector.
• Offices and business parks. Staff and visitor parking that sits full through the generating day, workplace charging as a recruitment and retention amenity, and an ESG story for occupier and landlord. See the office investment property vertical.
• Multi-let estates and mixed-use schemes. Shared parking the owner controls as common parts, where a canopy plus charging is a fundable improvement that benefits every occupier. See the multi-let buildings vertical.

The poorer fit is the site with little surface parking, parking that empties during the day (so generation exports rather than self-consumes), or a roof that is already a cheaper, better home for the panels. In most cases a carport complements a rooftop array rather than replacing it — the roof carries the bulk of the generation at the lower cost per kWp, and the canopy adds capacity plus the amenity the roof can’t provide.

If you own a portfolio, the carport question is best answered asset by asset against roof condition, parking size and occupier mix. Our portfolio vertical and owner’s due-diligence guide set out how to rank sites and stage a rollout.

Frequently asked questions

Do I need full planning permission for a solar carport?

Often not. In England, Class OA permitted development allows solar canopies over off-street non-domestic parking without a full application, provided the canopy is no more than 4 metres high and at least 10 metres from any dwelling. You still need prior approval from the local planning authority for glare, siting and appearance, and the right is restricted on designated or listed sites — so confirm it applies to your specific car park before you commit, and budget for the glare assessment.

Why does a carport cost more than a rooftop system?

Because you are buying a building, not just a solar array. A rooftop install mounts onto a surface that already exists; a carport has to construct that surface — foundations, columns, beams and a load-rated canopy frame engineered to wind and snow. That steel structure pushes the cost per kWp above the typical commercial rooftop range. The trade-off is that a carport adds EV charging, sheltered parking and tenant amenity that a roof cannot, so the case rests on several value streams rather than generation alone.

Can the solar carport power EV chargers directly?

Yes, and that pairing is one of the main reasons to build one. The canopy structure provides the mounting and cable route, and daytime generation can feed AC chargers (typically 7–22kW) directly, soaking up power that would otherwise export at a lower rate. DC rapid chargers (50kW+) need their own grid capacity and pair well with a battery. The OZEV Workplace Charging Scheme is open to eligible businesses — check current eligibility on gov.uk. Our commercial EV charging guide explains how the two combine on a single site.