Solar Carport Cost Breakdown UK 2026: Price Per Bay and ROI Analysis
- Keith Lin
- Mar 24
- 4 min read
Updated: Apr 9
Last updated: 25 March 2026. All prices in this article are indicative estimates based on Q1 2026 market data. Contact KLY Solar for current structural frame kit pricing.
A commercial solar carport in the UK typically costs between £900 and £1,400 per kWp installed, or approximately £3,000 to £5,500 per parking bay depending on configuration. With current electricity prices at 25–27p/kWh for UK businesses (Ofgem Q1 2026), a 100-bay system generating around 200,000 kWh per year can deliver annual savings of £50,000–£54,000, with a typical payback period of 5–8 years.
What Drives the Cost of a Solar Carport?
Solar carport costs are higher than standard rooftop solar installations because you are building a structure (the steel canopy) as well as installing a PV system. The structural frame typically accounts for 40–55% of the total project cost, compared to rooftop solar where the mounting system is 5–10% of the total.
The main cost components are: structural steel frame (columns, rafters, purlins, bracing, base plates, hot-dip galvanising), foundations (pad footings, piled foundations, or ground screws), PV panels, inverters, electrical installation (DC and AC cabling, switchgear, metering, earthing), grid connection (DNO application fees, connection works, export metering), design and engineering (structural calculations, electrical design, planning/prior approval), and project management (site supervision, health and safety, commissioning).
Cost Breakdown by Component
The following shows indicative cost ranges for a 50-bay single cantilever solar carport (approximately 150 kWp) in the UK:
Structural steel frame (EN 1090-1, EXC2, galvanised): £90,000–£135,000 (40–50%)
Foundations (pad footings, standard soil): £20,000–£35,000 (10–15%)
PV panels (Tier 1, 550–600W bifacial): £30,000–£45,000 (15–18%)
Inverters (string, 3-phase): £10,000–£15,000 (5–7%)
Electrical installation + cabling: £15,000–£25,000 (8–10%)
Grid connection (G99, DNO works): £5,000–£15,000 (3–6%)
Design, engineering, prior approval: £8,000–£12,000 (4–5%)
Project management + commissioning: £5,000–£10,000 (3–4%)
Total (installed, grid-connected): £183,000–£292,000 | Cost per bay: £3,660–£5,840 | Cost per kWp: £1,220–£1,947
Notes: Costs assume standard ground conditions (no piling required), single cantilever configuration, and a standard G99 grid connection. Piled foundations can add £15,000–£40,000. Double cantilever configurations cost approximately 15–25% less per bay due to shared central columns. EV charging integration adds approximately £500–£1,000 per charging point for cable management.
Price Per Bay: Single vs Double Cantilever
Single cantilever: 1 row of parking, £3,500–£5,500 per bay, 2.5–3.5 kWp per bay
Double cantilever: 2 rows of parking, £2,800–£4,200 per bay, 2.5–3.5 kWp per bay
Double cantilever systems are more cost-efficient per bay because the central column structure serves two rows of parking simultaneously. However, they require wider open areas and are not suitable for all car park layouts.Revenue and Savings Model
A commercial solar carport generates value in three ways:
1. Self-Consumption Savings (Primary Value)
Electricity generated and consumed on-site displaces grid purchases at your commercial tariff rate. Current UK business electricity rate: 25–27p/kWh (Ofgem, Q1 2026). Typical self-consumption rate for commercial premises: 60–80%.
For a 150 kWp system generating approximately 135,000 kWh per year, self-consumption at 70% delivers: 94,500 kWh × 26p/kWh = £24,570 annual savings
2. Smart Export Guarantee (SEG) Income
Surplus electricity exported to the grid earns income under the SEG. Flat-rate tariffs (no battery): 12–16.5p/kWh. Time-of-use tariffs (with battery): up to 27p/kWh.
For 40,500 kWh of surplus export at 15p/kWh: 40,500 kWh × 15p/kWh = £6,075 annual income
3. Tax Relief
Annual Investment Allowance (AIA): 100% first-year deduction on qualifying capital expenditure up to £1 million per year.
Full Expensing: For incorporated businesses, 100% first-year deduction with no cap on main rate assets.
Business rates exemption: 100% exemption for new solar installations from April 2023 to 2035.
For a corporation tax-paying business investing £250,000, the AIA delivers a £62,500 tax saving in year one (at the 25% corporation tax rate).
Payback Period Calculation
Using the 150 kWp example: Self-consumption savings (70% at 26p/kWh): £24,570/year. SEG export income (30% at 15p/kWh): £6,075/year. Total annual benefit (pre-tax): £30,645. Year 1 tax saving (AIA, 25% corp tax): £62,500 (one-off).
Net investment after Year 1 tax relief: £250,000 − £62,500 = £187,500
Simple payback: £187,500 ÷ £30,645 = 6.1 years
With 3% annual electricity price inflation: approximately 5.4 years
These calculations are conservative. Higher self-consumption rates and higher SEG tariffs (with battery storage) can reduce payback to under 5 years.
Cost Reduction Strategies
1. Choose Double Cantilever Where Possible
15–25% lower cost per bay due to shared column infrastructure.
2. Procure the Frame Kit Supply-Only
Buying the structural frame direct from a supply-only manufacturer like KLY Solar and using your own EPC for installation can save 20–35% compared to a fully turnkey price.
3. Standardise Across Multiple Sites
For portfolio rollouts, standardised frame designs reduce engineering costs and enable volume pricing on steelwork.
4. Time Your Investment for Maximum Tax Relief
Ensure the investment is commissioned within the tax year to capture AIA or Full Expensing relief.
5. Integrate EV Charging
Adding EV charging infrastructure within the carport frame adds marginal cost (£500–£1,000 per point for cable management) but significantly increases the commercial value of the asset.
Frequently Asked Questions
How much does a solar carport cost per parking bay in the UK?
Between £2,800 and £5,500 per bay depending on configuration (single vs double cantilever), site conditions, and specification. Double cantilever systems are more cost-efficient per bay.
What is the payback period for a commercial solar carport?
Typically 5–8 years for a well-designed system with good self-consumption. After payback, the system generates net income for its remaining 25–30 year operational life.
Can I claim tax relief on a solar carport?
Yes. UK businesses can claim 100% first-year tax relief through the Annual Investment Allowance (up to £1 million) or Full Expensing. The full cost typically qualifies as capital expenditure.
Ready to get a cost estimate for your site? View our solar carport systems or contact us for a project-specific quotation.
About the Author
Keith Lin is the Director of KLY Solar (KLY Global Ltd), a UK supplier of solar carport structure kits for commercial project teams.
Sources cited in this article:
KLY GLOBAL LTD trading as KLY Solar | Company No. 14169672
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