What PAYG Solar Means for UK Businesses

What PAYG solar means for a UK business

PAYG solar for businesses usually means using solar panels on your premises without paying the full installation cost upfront. Instead, the business pays for the electricity generated, or pays a regular fee, under a longer-term commercial agreement.

For UK businesses, PAYG solar is not normally a single regulated product category. Suppliers may use the term to describe a commercial solar power purchase agreement, an equipment lease, or a subscription-style solar service.

The most common PAYG-style route for larger commercial sites is a solar power purchase agreement, usually called a solar PPA. In this model, a third party funds, owns, installs, operates, and maintains the system. The business then buys the electricity generated on site at an agreed rate. The basic idea is straightforward. The business avoids most or all of the upfront installation cost. The provider recovers its investment through electricity charges, lease payments, or service fees over the contract term. This can make solar easier to adopt, but it does not make the system free.

• In summary:
• PAYG solar can reduce upfront capital spending.
• The provider usually owns the system during the contract.
• The business normally needs strong daytime electricity demand.
• Contracts can run for many years.
• Outright ownership may deliver better lifetime returns.
• Roof, grid, metering, lease, and legal constraints can prevent a project from working.
• Export income and environmental claims depend on the contract.

The right answer depends on the site and the agreement. A cold store, factory, farm building, school, depot, hotel, office, or leisure centre with steady daytime electricity use may be a good candidate. A shaded roof, short lease, weak electrical infrastructure, roof nearing replacement, or restrictive contract can make PAYG solar difficult or unsuitable.

The main PAYG solar models

For UK businesses, PAYG solar normally falls into three broad models. The wording used by suppliers can vary, so the contract matters more than the headline label.

• Solar PPA: A third party pays for and owns the solar PV system, then sells the electricity generated on site to the business at an agreed pence-per-kWh rate.
• Solar lease: The business pays a fixed rental amount for use of the solar equipment, while ownership may remain with the lessor during the term.
• Solar subscription: The business pays a regular fee for an agreed solar service package, usually including operation, monitoring, and maintenance.
• Outright purchase: The business buys the system itself, owns the asset, and keeps more control over export income, maintenance choices, and long-term financial benefit.
• Who owns the equipment.
• Who receives export income.
• Who is responsible for repairs and replacements.
• What happens if the roof needs work.
• What happens at the end of the term.
• How early termination is handled.

A PPA is often the closest match to “pay as you go” because the business pays for solar electricity produced and used, rather than buying the panels. The agreed PPA rate is usually intended to be lower than the business’s grid import tariff. The true saving depends on the full electricity contract. It also depends on how much solar power is used on site at the time it is generated. A lease works differently. The payment may be fixed even if solar output varies. That can help with budgeting, but it makes performance guarantees, downtime provisions, and maintenance obligations especially important. A subscription-style offer may bundle design, installation, monitoring, maintenance, and support into one service. This can be convenient, but the business should still check the key commercial points: The same solar panels may be used under each model. The important difference is who owns the asset, who carries the risk, and who keeps the long-term value.

How the electricity and money flow

Under a typical commercial solar PPA, solar panels generate electricity on the business premises. The building uses that power first where there is demand at the same time.

If the building needs more power than the solar system is producing, it imports electricity from the grid as usual. If solar generation is higher than site demand, the surplus may be exported.

Export income belongs to whoever the contract says it belongs to. In many PAYG arrangements, the asset owner keeps export revenue because it funded and owns the system. In some deals, export value may be shared or reflected in the price offered to the site user. Metering is central to fair billing. A PPA normally relies on generation metering. The main import meter records electricity bought from the supplier, while an export meter records surplus electricity sent to the grid. Poor metering design can cause disputes. This is especially true where there are multiple supplies, sub-meters, tenant areas, temporary shutdowns, or complex site operations.

• A good PAYG contract should explain:
• How metered solar generation is billed.
• What happens if a meter fails.
• Who can access generation and consumption data.
• How estimates are made during outages.
• How billing disputes are resolved.
• Whether standing charges, levies, or other electricity contract costs are affected.

These details are not just administrative. They determine whether the commercial saving can be verified over time. The grid supply also remains necessary. Solar output changes with daylight, weather, season, and system availability. PAYG solar can reduce imported electricity, but it rarely removes the need for a grid connection.

Why businesses consider PAYG solar

The main attraction is avoiding a large upfront capital cost. Buying a commercial solar system outright can require significant expenditure, even though commercial solar can be cost-effective over the long term.

PAYG solar can allow a business to use its capital elsewhere while still reducing exposure to grid electricity costs.

It can also shift some operational responsibility to the provider. In many PAYG models, the provider deals with monitoring, maintenance, inverter repairs, performance checks, and system insurance. This can suit businesses that do not want to manage a generation asset directly.

• PAYG solar may be relevant where the business has:
• A suitable roof or land area.
• Stable long-term occupancy.
• Strong daytime electricity demand.
• Limited appetite for upfront capital spend.
• A preference for a managed service.
• A contract that allocates risks clearly.

It can also suit some landlord and tenant situations, but only if the legal structure works. The agreement must clearly set out who benefits from the electricity, who grants roof rights, and who remains liable if the tenant leaves. The trade-off is reduced flexibility. A business that buys the system outright usually has more control over the asset, export arrangements, future battery integration, maintenance choices, and end-of-life decisions. If the business can fund the system and expects to occupy the site long term, outright ownership may produce a stronger lifetime financial outcome. PAYG is therefore a financing and risk-allocation decision. It is not just a solar technology decision. The panels may look the same on the roof, but the commercial result can be very different.

What makes a site suitable

The starting point is not roof size alone. A large roof with poor electricity matching can produce less value than a smaller roof serving a site with steady daytime demand.

Half-hourly electricity data is often the best starting point. Annual kWh totals can hide seasonal closures, weekend shutdowns, night shifts, and short demand peaks.

Roof condition is equally important. Solar panels can last longer than some roof coverings. A roof close to replacement is a poor candidate unless reroofing is planned first. Removing and reinstalling panels later can be expensive and disruptive. Under a third-party ownership model, it can also be contractually awkward. Structural capacity must be checked. Commercial roofs may have limited spare load capacity, especially where flat-roof systems need ballast. Wind uplift, edge zones, roof membrane compatibility, roof lights, fragile materials, drainage routes, and safe maintenance access all affect the design. Electrical infrastructure can also limit the scheme. The main LV panel may need spare capacity or modification. Cable routes can be costly. Inverter locations need to allow for access, heat management, noise, and cable length. Older switchgear or limited transformer capacity can reduce the viable system size.

• Common suitability checks include:
• The business uses electricity during daylight hours.
• The roof is in good condition.
• The structure can take the additional load.
• Shading from plant and nearby buildings is limited.
• The site has safe access for installation and maintenance.
• The lease or ownership position allows long-term consent.
• The local grid can accept the proposed connection.
• The electrical infrastructure can accommodate the system.
• The contract length matches the site occupation plan.
• Insurer, fire safety, and landlord requirements can be met.

A site can fail on any one of these points. For example, a tenant with only a few years left on its lease may struggle to sign a long PPA, even if the roof and demand profile are excellent.

Grid connection, planning, and government support

Most commercial solar projects need approval from the Distribution Network Operator, known as the DNO. The DNO is the local electricity network operator, not the electricity supplier.

Many commercial systems fall under G99 connection rules. Only smaller systems may fall under G98.

Export capacity is not guaranteed. The DNO may allow generation but limit export. It may also require export limitation equipment. Larger projects can need connection studies, protection settings, witness testing, or network reinforcement. These steps can affect both project timing and cost. Planning rules also need checking. Rooftop commercial solar is often permitted development in England, subject to conditions. Extra consent may be needed for listed buildings, conservation areas, scheduled monuments, protected sites, and visually sensitive locations. Scotland, Wales, and Northern Ireland have their own planning regimes, so local advice may be needed. UK government support for business solar is more limited than historic subsidy schemes. The Feed-in Tariff and Renewables Obligation are closed to new applicants. The Smart Export Guarantee can pay for exported electricity from eligible low-carbon generation up to 5 MW. Under a PAYG arrangement, it is often more relevant to the system owner than to the site occupier. The contract should state who receives any export payments. There may be local authority or regional business decarbonisation grants, but availability changes by area and funding round. Businesses should avoid assuming grant funding is available until it is confirmed in writing. Businesses buying assets may also need to consider capital allowances, VAT treatment, and business rates treatment. Under a PAYG model, ownership-related tax benefits may sit with the funder rather than the occupier. Government policy can influence solar investment, grid reform, planning rules, and tax treatment. It does not remove site-level constraints. Roof condition, connection capacity, contract risk, and electricity use still decide whether a PAYG project works in practice.

Contract terms that matter

The contract is where many PAYG solar risks sit. A low starting tariff can look attractive, but indexation, contract length, minimum purchase obligations, termination charges, export rights, and roof works provisions can change the value significantly.

• Key terms to review include:
• PPA rate: The agreed unit price determines the immediate saving against grid imports, but it should be tested against the business’s actual demand profile.
• Indexation: An annual uplift linked to inflation or a fixed increase can materially affect long-term costs.
• Contract length: Longer terms may support a lower rate, but they reduce flexibility if the business changes premises or operations.
• Minimum purchase obligations: Some contracts require payment for solar electricity generated and consumed on site, or include deemed generation if the business causes an outage.
• Export treatment: The contract should state who receives export revenue and who can claim any environmental attributes.
• Roof works procedure: The agreement should say who pays for temporary removal and reinstatement if roof maintenance is needed.
• Maintenance scope: Response times, monitoring duties, inverter replacement, cleaning assumptions, and spare parts responsibility should be clear.
• Metering and billing: The contract should explain how generation is measured, how errors are corrected, and how disputes are handled.
• Insurance and liability: The parties should understand who insures the system, the roof interface, and any business interruption risk.
• Assignment rights: The contract should explain what happens if the property is sold or the tenant changes.
• End-of-term options: The business should know whether the system is removed, transferred, bought out, or extended.

Early termination provisions deserve particular attention. If the site is sold, the tenant leaves, the roof is redeveloped, or operations change, the business may face buyout costs or assignment requirements. These clauses should be understood before signing. They should not be discovered during a property transaction. Carbon reporting also needs care. The contract should clarify who can claim renewable energy benefits, including any Renewable Energy Guarantees of Origin where relevant. Businesses should avoid double counting if export rights or environmental attributes are held by another party. A fair PAYG agreement should make the commercial position clear in plain English. If the saving depends on assumptions, those assumptions should be visible and testable.

PAYG solar compared with buying outright

PAYG solar and outright purchase can both use the same panels, inverters, mounting systems, and monitoring equipment. The difference is commercial control.

PAYG usually lowers upfront cost and shifts some responsibility to the provider. Ownership usually gives more flexibility and potentially more lifetime value.

A business choosing between the two should not look only at the first-year saving. It should compare:

• Total contract cost.
• Avoided grid imports.
• Export value.
• Maintenance obligations.
• Tax treatment.
• Insurance requirements.
• Future site plans.
• Opportunity cost of using capital.
• End-of-term rights.
• Early exit risk.

PAYG may be the better fit where capital is limited, the business wants a managed service, and the contract is fair. Outright purchase may be better where the business has available funds, strong long-term site control, and the appetite to manage the asset. Batteries add another decision. They are not automatically included in PAYG solar and can increase both cost and contract complexity. Battery storage may help if demand peaks occur outside solar hours, or where the business wants to reduce some peak import charges. It should be modelled using half-hourly data rather than assumed as standard. The best design is not always the largest possible roof coverage. Fire access routes, roof lights, wind loading, shading, grid export limits, cable routes, and maintenance access often reduce the practical system size. In many commercial projects, using more solar on site is more valuable than exporting a larger surplus.

Common mistakes to avoid

A frequent mistake is treating PAYG solar as free solar. The business is still paying, just through a different structure. The provider’s costs and return are recovered through the PPA tariff, lease fee, or service payment.

Another mistake is comparing headline rates without reading the terms. A lower initial pence-per-kWh rate may be less attractive if it has strong indexation, poor flexibility, high termination charges, or unfavourable export treatment.

Some businesses also assume every roof should be filled with panels. In practice, roof access routes, fire strategy, shading, structural load, wind uplift, DNO limits, and maintenance requirements shape the final array. An installer-level design is not just a panel count on a satellite image. Operational disruption is often underestimated. Surveys, access equipment, scaffolding, shutdowns, permits to work, site inductions, asbestos checks, roof warranties, insurer requirements, and landlord consent can all affect the programme.

• The most useful early questions are practical ones:
• Is the roof likely to need replacement during the contract?
• Does the business have enough daytime electricity demand?
• Is the lease long enough for a third-party-owned system?
• Can the DNO accept the proposed generation and export?
• Who receives export income?
• What happens if the business moves or sells the site?
• Who pays if panels must be removed for roof works?
• How is underperformance identified and corrected?
• What happens if the site’s electricity use falls?
• Can the contract be assigned to a new occupier or owner?

Good projects usually start with evidence. Useful documents include half-hourly consumption data, roof information, electrical drawings where available, lease details, and a realistic view of future site plans. Without that evidence, PAYG savings are easy to overstate.

Practical next steps

A business considering PAYG solar should first collect the information needed for a proper assessment. This usually includes recent electricity bills, half-hourly data if available, roof drawings or survey information, lease documents, and any known plans for reroofing, EV charging, heat pumps, building expansion, or relocation.

The next step is to compare PAYG with outright purchase and conventional finance. The cheapest-looking option at the start may not be the best option over the life of the system.

The comparison should include ownership, maintenance, export value, tax position, contract flexibility, and end-of-term rights. For a serious proposal, ask providers to model the system using real consumption data rather than annual averages. The proposal should show expected self-consumption, export assumptions, grid connection requirements, maintenance scope, metering method, and contract risks in plain terms. PAYG solar can be a practical route for UK businesses that want solar without a large upfront spend. It works best when the site has good daylight electricity use, a suitable roof, stable occupancy, a workable grid connection, and a contract that clearly allocates cost, risk, ownership, and value. If you are weighing up PAYG solar, a PPA, or buying a commercial solar system outright, compare the options before committing. A site-specific assessment can show whether the numbers, roof, grid connection, and contract structure are likely to work for your business.