O&M Agreements UK: Energy Project Contracts Guide
We're not a law firm — we help you find the right legal support. For advice on your situation, speak to a legal adviser or find a solicitor.
If you are developing or running a solar farm, wind project, battery storage site or any other renewable energy asset, an Operation and Maintenance (O&M) agreement is one of the most commercially significant contracts you will put in place. It governs how your asset is looked after day to day, how problems get fixed when things go wrong, and how performance is measured across what is often a 20 to 25 year operating life.
Get it right and you have a predictable, bankable asset. Get it wrong and you can find yourself arguing about who pays for a failed inverter while your revenue stalls. This guide walks through what an O&M agreement typically covers, the clauses that tend to cause the most friction, and the commercial levers worth thinking about before signing.
What this document is
An O&M agreement is the contract between the owner of a renewable energy project and a specialist contractor (the O&M provider) who takes on responsibility for operating the site and keeping the equipment running. It sits alongside the other core project contracts, typically an Engineering, Procurement and Construction (EPC) contract, a Power Purchase Agreement (PPA), a grid connection agreement and the underlying land rights.
The O&M provider's role begins once construction is complete and the asset moves into commercial operation. Depending on how the deal is structured, the scope can range from 'light touch' asset management (monitoring, reporting, scheduling third parties) through to full service O&M where the contractor takes on almost everything, including staffing, spares, corrective repairs and performance guarantees.
In the UK market, O&M contracts are commonly used for solar PV, onshore and offshore wind, battery energy storage systems (BESS), anaerobic digestion and hydro projects. The shape of the agreement will look quite different depending on which technology is involved.
How to use this document
- Define the technology and scope early. Before drafting begins, be clear about what is being operated and maintained. A solar PV farm needs a very different scope from a battery storage site or a wind turbine. List the assets in scope, the battery limits (where the O&M provider's responsibility starts and ends), and which items sit outside the contract such as grid connection equipment owned by the DNO.
- Pin down the service categories. Separate preventive maintenance (scheduled inspections, cleaning, servicing), corrective maintenance (fault diagnosis, repairs, replacements), and monitoring and reporting obligations. Each category should have its own response times, reporting cadence and acceptance criteria. Ambiguity here is where most disputes begin, so the more specific the scope schedule, the better.
- Agree the performance regime. Most O&M agreements include some form of availability guarantee or performance ratio target, with liquidated damages if the contractor falls short and sometimes a bonus if they outperform. Make sure the formula for calculating availability is watertight, that force majeure and grid outages are properly carved out, and that the caps on damages are commercially realistic.
- Deal with spares, warranties and major components. Work out who owns the spares inventory, who pays for consumables, and how warranty claims against the original equipment manufacturer are handled. For wind and BESS projects, major component replacement (gearboxes, blades, battery modules) often sits outside the standard O&M fee and needs its own pricing mechanism.
- Lock down termination, step-in and handover. The contract should set out clear termination rights for persistent underperformance, insolvency and material breach, along with a workable handover process at the end of the term. Lenders financing the project will usually want direct step-in rights, so a separate direct agreement with the funder is often needed.
Common questions
Q How long do O&M agreements typically run for?
Terms vary, but it is common to see initial periods of 5 to 10 years with options to extend, sometimes aligned to the expected life of the asset or to key warranty periods on the main equipment. Some owners prefer shorter terms to retain leverage and retender the contract, while others want longer terms to lock in pricing and service levels. The right answer depends on your financing structure and risk appetite.
Q What is the difference between preventive and corrective maintenance?
Preventive maintenance is planned work carried out on a schedule to reduce the chance of failures, such as routine inspections, cleaning of solar panels, torque checks and oil changes. Corrective maintenance is reactive work done when something breaks or underperforms, such as replacing a failed inverter, repairing a damaged cable or resetting a tripped protection relay. A good O&M agreement will cover both, with clear response times for corrective work.
Q Who takes the risk if the project underperforms?
This depends on how the performance regime is drafted. Many O&M contracts include an availability guarantee, where the contractor pays liquidated damages if the asset is offline beyond agreed thresholds for reasons within their control. Events outside their control, such as grid outages, weather-related curtailment or force majeure, are usually excluded. The exact allocation of risk is heavily negotiated and often reflects who has priced for what.
Q How does an O&M agreement interact with the EPC warranty?
During the EPC defects liability period, the construction contractor is normally responsible for putting right defects in the works. The O&M provider will often be tasked with identifying and reporting these issues, and in some cases managing warranty claims on the owner's behalf. The two contracts need to dovetail, so that there are no gaps in responsibility and no double recovery, particularly around the handover from EPC to operations.
Q Are there specific UK regulations I need to think about?
Yes. Depending on the technology and site, you may need to consider health and safety law (including CDM 2015 where construction or significant works are involved), electricity licensing and grid code obligations, environmental permits, and any conditions attached to subsidy or support schemes such as the Contracts for Difference regime or legacy Renewables Obligation or Feed-in Tariff arrangements. The O&M contract should require the contractor to comply with all applicable law and site-specific consents.
Q Can the O&M provider subcontract the work?
Most O&M agreements allow subcontracting, particularly for specialist tasks such as high-voltage switching, rope access work on wind turbines or battery module replacement. The owner will usually want approval rights over key subcontractors, a requirement that the main contractor remains fully responsible for the subcontractor's performance, and flow-down of key obligations such as insurance, health and safety and confidentiality.
Q What happens at the end of the agreement?
The contract should set out a handover process covering things like the return of spares, transfer of monitoring data and SCADA access, delivery of maintenance records, cooperation with an incoming contractor and any final performance testing. Owners often underestimate how important a clean handover is, especially if the outgoing contractor is being replaced after a dispute. Getting this right avoids data gaps and operational disruption.
Sources
This guide is based on primary UK law and official guidance.
- Guidance · UK GovContracts for Difference scheme (gov.uk)gov.uk
- Guidance · UK GovHSE – Construction (Design and Management) Regulations 2015hse.gov.uk
- Guidance · UK GovPlanning for renewable and low carbon energy (gov.uk)gov.uk
Legal disclaimer
This article is for general information only. It is a tool to help you find your way — not legal advice, and not a substitute for speaking to a qualified adviser about your situation.