How much does a 1MW commercial solar system cost in 2026?
1MWp commercial solar is the threshold where projects start to look like infrastructure assets rather than facility upgrades. DNO engagement is substantial (often dedicated 11kV connection, AVR, sometimes new transformer capacity), structural design requires full engineered assessment of the entire roof system, and project finance tends to involve multi-party stakeholder management. Per-Wp pricing reaches the cleanest commercial tier — but the absolute capital is large enough to need a structured finance decision.
£720,000–£950,000
£700–£900
950 MWh
2.6–3.5 years
Cost breakdown — where the money goes on a 1MW project
Hardware (modules, inverters, mounting)
£395k–£470k
Cleanest volume tier — £0.40–£0.47/Wp on hardware. Central inverter architecture standard. Cable runs more substantial.
Installation labour (M&E, roof access)
£115k–£160k
Substantial multi-month project with 8–14 crew. Specialist mechanical handling. Often staged across multiple roof sections.
Soft costs (DNO, structural, design)
£90k–£135k
DNO at 1MW is significant — connection studies £15k–£25k, dedicated transformer often required £40k–£80k, AVR fitting standard. Full geotechnical and structural engineering.
Commissioning & certification
£35k–£50k
Multi-stage commissioning, full IEC 62446 testing, comprehensive monitoring portal with sub-array breakdown.
Margin and contingency
£75k–£115k
Margin compressed (8–10%) at scale but project complexity needs more contingency (5–7%). Multi-stage payment terms typical.
Worked example: 1MW commercial solar at central pricing
£825,000
£103,125 corp tax saved (50% FYA × 25%)
£200k (950MWh × ~21p blended)
-£522k (after capex, FYA, savings)
16–22%
3.3–4.8 years
Run your own numbers in our interactive calculator →
Best fit
Industrial portfolio owners, mega-distribution operators, automotive plants with continuous shift operations, NHS regional estates with PSDS bundled funding, energy-intensive food production, large agricultural cooperatives with seasonal demand profiles.
Best for
A 1MW system suits industrial estate / portfolio anchor, mega-warehouse operator, automotive plant, NHS regional estate, multi-academy trust portfolio, large agricultural cooperative.
Not suitable
Sites where DNO reinforcement would exceed £100k, locations with restrictive planning constraints around large-format commercial PV, organisations without clear long-term occupation horizon (10yr+ minimum).
Other system sizes
100kW system cost
£850–£1,100 per kWp
200kW system cost
£800–£1,000 per kWp
500kW system cost
£720–£900 per kWp
1MW cost FAQs
Is 1MW too big for my industrial site?
Does AIA still apply at 1MW?
What financing is appropriate for £800k+ projects?
How do battery + 1MW solar economics work?
What lead time should we plan for a 1MW project?
1MWp commercial solar cost guide 2025
A 1MW (1,000kWp) commercial solar installation costs £700,000–£950,000 for a roof-mount system, or £800,000–£1,100,000 for a ground-mount installation. At utility-approaching scale, the economics are compelling: cost per kWp falls to £700–£950, and the Annual Investment Allowance covers the full £1m threshold — maximising the year-one tax benefit.
After AIA at 25% Corporation Tax, the effective net cost of a £800,000 system is just £600,000. For large manufacturing, logistics, or data centre sites consuming 1,000,000+ kWh annually, payback is typically 3–5 years — making 1MWp one of the most financially compelling capital investments available to UK businesses.
1MWp system cost breakdown
| Component | Specification | Typical cost range |
|---|---|---|
| Solar panels (430–440Wp bifacial N-type) | 2,300–2,400 panels, premium tier-1 bifacial | £230,000–290,000 |
| Inverters (central or string) | 4x 250kW or 10x 100kW string inverters, 10yr warranty | £65,000–90,000 |
| Mounting system | Engineered roof or ground mount, certified structural design | £80,000–130,000 |
| MV/LV electrical infrastructure | MV switch room, LV distribution, protection relays, metering | £60,000–100,000 |
| SCADA monitoring system | Advanced generation monitoring, power quality, fault alarms | £12,000–20,000 |
| DNO connection (G99 formal) | G99 application, protection scheme, potential HV connection | £10,000–150,000+ |
| Civil and groundworks (ground mount) | Piling, cable trenching, security, CCTV | £40,000–80,000 |
| Project management and design | Full engineering design, project management, CDM coordination | £20,000–35,000 |
| Planning and consents | Pre-application, planning application, environmental studies | £15,000–60,000 |
| Commissioning, testing, MCS | G99 commissioning, protection testing, MCS certification | £8,000–15,000 |
Grid connection for 1MWp: the key variable cost
Grid connection cost is the most variable and potentially significant additional cost for 1MWp systems. The connection cost depends on the existing capacity at the site and the proximity to suitable grid infrastructure. For sites with existing 400V three-phase supplies, G99 costs might be as low as £10,000–20,000. For sites requiring new HV (11kV) connections or grid reinforcement, costs can reach £150,000–500,000+.
How to manage grid connection risk
Always request a DNO pre-application enquiry (PAE) before committing to a 1MWp project. The PAE identifies connection requirements and provides a budgetary cost estimate. Many sites have existing capacity that makes connection straightforward; others require significant investment. Knowing this early prevents costly design work on infeasible projects.
Export limitation as a cost-control tool
If grid connection costs are prohibitive, an export limitation system (using active power control to cap export at a lower level) can reduce DNO connection costs significantly. A 1MWp system with 500kW export limit may cost substantially less to connect than one requiring full 1MW export capacity.
1MWp energy generation and financial returns
| Location | Annual generation | Annual saving (£0.27/kWh) | SEG income | Total annual benefit |
|---|---|---|---|---|
| South England | 900,000–950,000 kWh | £243,000–256,500 | £27,000–28,500 | £270,000–285,000 |
| Midlands | 840,000–890,000 kWh | £226,800–240,300 | £25,200–26,700 | £252,000–267,000 |
| North England | 790,000–840,000 kWh | £213,300–226,800 | £23,700–25,200 | £237,000–252,000 |
| Scotland | 760,000–820,000 kWh | £205,200–221,400 | £22,800–24,600 | £228,000–246,000 |
Financing a 1MWp system
At 1MWp scale, sophisticated financing structures become available that are not practical for smaller systems. The AIA cap of £1m means that on a system costing exactly £1m, the entire cost is deductible against taxable profits in year one — a £250,000 Corporation Tax saving.
| Finance method | Upfront cost | AIA benefit | Annual net benefit | Notes |
|---|---|---|---|---|
| Cash purchase | £700k–950k | £175k–237k (25% CT) | £255k–275k (full generation) | Best total return |
| Green loan (6.5%, 10yr) | £0 | £175k–237k (yr1 AIA) | ~£185k–210k net of repayments | Cash flow neutral yr1 |
| Project finance (SPV structure) | Minimal (equity slice) | At SPV level | Varies by structure | For 1MW+ large corporate |
| PPA (£0.07/kWh) | £0 | £0 | ~£180k–210k (PPA discount) | Zero capital; no AIA; no asset |
Planning permission for 1MWp
Ground-mount solar above 1MWp in England always requires full planning permission. Roof-mount systems at 1MWp may still qualify as permitted development depending on the building type, location, and local planning authority guidance. Always confirm planning status before committing to design.
Planning permission process
Full planning application for a 1MWp ground-mount system takes 3–8 months. Allow for pre-application consultation, community engagement, environmental screening, bat/bird surveys, glint and glare assessment, visual impact assessment, and flood risk assessment. Budget £15,000–60,000 for professional planning support.
National planning policy for solar
NPPF (National Planning Policy Framework) supports solar energy development in principle. Local planning policies vary — some LPAs have pro-solar policies (particularly those with climate emergency declarations); others impose restrictions in AONB, Green Belt, and conservation areas.
Battery storage at 1MWp scale
A 1MWp system pairs naturally with a 500kWh–2MWh battery system. Battery storage at this scale enables frequency response participation (FFR/DC ancillary services), demand-side response contracts, and smart export maximisation — potentially adding £20,000–60,000/year in additional revenue beyond energy bill savings.
Battery storage cost at 1MWp scale
500kWh battery: £250,000–350,000. 1MWh battery: £480,000–650,000. Battery storage qualifies for AIA alongside solar panels (within the £1m annual allowance cap, or using 50% First Year Allowance for larger combined investments). ROI on battery addition: typically 8–14 years at current rates.
Get a comparable 1MW cost benchmark for your specific site
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