Thames Water has gone out to tender with an AMP8 contract for photovoltaic (PV) installations at at two separate sites in Little Marlow and Maidenhead.

NOTE: THE PSQ SUBMISSION DEADLINE HAS BEEN CHANGED TO 22 SEPTEMBER 2026 AT 12:00PM.

The PV installations are at two separate sites, both being ground mounted, with a maximum capacity of 1,000kWAC and 450kWAC. The supplier will be required to design and optimise the size of the PV installation for behind-the-meter and achieve an attractive payback period and NPV.

The scope will be awarded be via either an EPC or PPA (Power Purchase Agreement) model, with only one to be awarded.

Scope of work includes the finance, engineering, design, procurement, construction, testing and completion, and to operate and maintain the two separate solar photovoltaic (PV) plants as summarised in the following non-exhaustive list:

• Full design and engineering
• Procurement
• Installation
• Commissioning
• Distribution Network Operator (DNO) witnessing, testing and approval to satisfy the terms of the connection agreement or offer
• Supporting OFGEM accreditation for REGOs
• Operation and maintenance
• Monthly and annual reporting
• Training of emergency procedures
• Training of essential operational activities
• Documentation
• Demarcation fencing and signage
• Biodiversity net gain requirements and any visual impact requirements

Thames Water is advising interested suppliers to read this section before deciding whether they wish to register for this event.- this provides information regarding the scope of the procurement and details some of the key requirements that a successful applicant MUST be able to deliver.

The following conditions would be considered as some of key requirements for a supplier to meet to be considered for this opportunity:

• Achilles Verification
• Must have relevant experience to plan, manage and monitor the project
• Must be able to comply with water industry standards, such as WIMES, where asset interaction is required

Current estimated start and end contract dates are 30 April 2027 to 29 April 2042 with a further possible extension option up to 29 April 2052.

The contract is being tendered in two separate Lots as follows:

• Lot 1. Supply and Installation (EPC)
• Lot 2. Fund, Design, Build, Ownership, Operation & Maintenance (PPA)

For Lot 1 Thames Water envisages that the contract will be awarded for an initial term of 5 years, with no extension options.

For Lot 2, Thames Water envisages that the contract will be awarded for an initial term of 15 years with options to extend by 5 year or longer, up to a maximum overall term of 25 years.

All bidders are required to complete a Procurement Specific Questionnaire (PSQ) regardless of the Lots applied for. Each bidder must then separately complete each 'Lot Specific' questionnaire relevant to the Lots they wish to apply for.

Each Lot will be evaluated individually with each Lot survey totalling 100%. Pass/Fail answers from the General PSQ will be combined with the scores from each Lot Specific survey completed to give an overall score out of 100% for each lot applied for.

Bidders may bid for one or both Lots. Responses to the PSQ will be evaluated against selection criteria, to select bidders to proceed to the next stage of the procurement process.

The selection criteria will be a combination of financial and non-financial factors and will include:

a) Legal and financial capacity to perform the contract;

b) Technical ability to perform the contract

Deadline for submission of enquiries about the tender is 5:00pm on 8 September 2026. Deadline for submission of the Procurement Specific Questionnaire (PSQ) is 12:00pm on 15 September 2026.

Click here to access the Procurement Specific Questionnaire online form.