UK industrial construction tenders: how to bid into AMP8, RIIO-3 and the energy transition pipeline
Updated: Sep 29
By Roman Bazelchuk | NEC Accredited Project Manager | APMG Project Planning and Control
Founder, NEC Planning Solutions Ltd
UK industrial construction tenders are won on the dates the client controls, such as an outage window or a plant shutdown, and on the long-lead equipment that must arrive first. Bidders who win AMP8, RIIO-3 and carbon capture work show those constraints as logic in the tender programme rather than in the narrative.
Much of what decides a UK tender applies to industrial work in the same way it applies to a school or a highway. The Procurement Act 2023 governs how most of it is let, and evaluators read the programme as evidence of deliverability rather than a picture of intent. Our guide to what NEC tender bids are really scored on covers that ground, so it is not repeated here.
What changes on industrial work is who owns the dates that matter. A water company decides when a treatment stream can come out of service. On the transmission system, outage needs are identified up to six years ahead, and the National Energy System Operator publishes the final plan for the coming year at the end of week 49, typically with around 2,500 outages in it. A refinery or process plant takes its big shutdowns years apart and fixes their dates long before a contractor is appointed. The contractor’s programme has to fit inside those dates and show that the equipment will be on site before they arrive.
Miss one of those dates and the loss is rarely measured in weeks. It is the gap to the next window, which on a transmission connection can be a year and on a process plant can be longer. That asymmetry is what an evaluator on an industrial framework is testing when they open a tender programme. Whether a small package needs a tender programme at all is a separate question with its own answer.
Where UK industrial construction tenders are coming from
Water is the largest single source. Ofwat’s final determinations for 2025 to 2030, the period the industry calls AMP8, allowed £104 billion of expenditure in 2022/23 prices, against £62 billion for the previous five years. Five companies took their settlements to the Competition and Markets Authority, which added £463 million in March 2026, 17 per cent of what they had asked for. The government has committed to replacing Ofwat with a new regulator, but the money for this period is set and the frameworks that deliver it are calling off work.
Power networks come next. Ofgem’s RIIO-3 price control for electricity transmission and the gas networks runs from 1 April 2026 to 31 March 2031, and its final determinations in December 2025 approved £28.7 billion of upfront investment within a pipeline of around £90 billion. The gas distribution companies have appealed to the CMA, which is due to decide by the end of October 2026. Electricity distribution stays on its own control, RIIO-ED2, until March 2028.
The energy transition work arrives project by project. In carbon capture, Net Zero Teesside Power and the Northern Endurance Partnership reached financial close in December 2024, Eni’s Liverpool Bay transport and storage project followed in April 2025, and two HyNet capture plants, at Padeswood and Protos, signed their contracts that September. Sizewell C took its final investment decision in July 2025 at around £38 billion, and in the same month Tata Steel broke ground on its £1.25 billion electric arc furnace at Port Talbot.
For a contractor the headline numbers matter less than what sits inside them. Most of this money will be spent on assets that have to keep running while the work is done, and most of it reaches the supply chain through frameworks and call-offs. The packages specialists actually win look more like the £20 million facility at Northwich in our carbon capture plant case study than like Sizewell C.
How industrial work is let in 2026
The Procurement Act 2023 came into force on 24 February 2025 and brought utilities into the same statute as other public buyers. Its utilities rules cover private utilities as well as public ones where they carry out a utility activity under special or exclusive rights, which is how the regulated water companies come within it, and they replace the Utilities Contracts Regulations 2016. Devolved Scottish authorities remain under their own rules.
In practice the value arrives through long frameworks with work called off package by package, so a specialist often competes twice: once to get onto a framework or a partner’s supply chain, and again for each call-off. National Grid’s Great Grid Partnership, for example, sits on its own enterprise agreement with call-off contracts on the NEC4 family for individual packages, and Yorkshire Water’s market notice for its AMP8 contract management system asked for one that supports the administration of NEC4 contracts.
Process plant is less uniform. Owners there commonly contract on the IChemE forms, the Red Book for lump sum work and the Green Book for reimbursable, while plant supply and installation packages often run on MF/1, which the IET issued in its seventh revision in 2024. The vocabulary shifts with the form. Under the IChemE Red Book the project manager approves the contractor’s programme, where under NEC4 the Project Manager accepts it and the result is the Accepted Programme. On FIDIC contracts clause 8.3 governs the programme, and our comparison of FIDIC and NEC practice sets out where the two diverge.
Social value and carbon still carry real marks on these frameworks, and our guide to scoring social value in UK construction tenders deals with them. The rest of this article stays with the part that is peculiar to industrial work.
The outage window is a date you do not own
An outage window is the period in which the client takes part of a live asset out of service so that new plant can be connected or old plant replaced. On a transmission connection it is a switching outage agreed through the system operator. At a water treatment works it is the time a stream can be isolated without putting supply at risk, usually outside the months of peak demand. On a process plant it is the turnaround, when the unit stops.
Each has the same property. The contractor cannot move it, and missing it does not cost the length of the miss. It costs the wait for the next one. Figure 1 shows the arithmetic on an illustrative connection where the transformer order goes out two months later than the tender assumed.
Two things follow for the tender programme. The window belongs on it as a fixed constraint, dated from the tender documents, rather than as a bar the contractor has drawn where it suits. Every activity that must finish before the window, above all the delivery of long-lead equipment, then needs visible float to the window’s opening and a note of what happens if that float is used. An evaluator who can see eight weeks between delivery and outage, with the next window named as the fallback, is looking at a programme built around the client’s asset rather than the contractor’s own sequence.
Long-lead equipment and the order before the contract
The window matters as much as it does because the equipment takes so long to arrive. In its original supply chain study for the Department for Energy Security and Net Zero, Baringa reported lead times of 24 months for 132 kV transformers and four years for 400 kV units, and its 2026 update heard 18 and 24 months respectively in more recent interviews, from a sample it describes as small. The International Energy Agency put large power transformers at up to four years in 2025 and cables at two to three, twice as long as in 2021.
Ofgem has responded with an Advanced Procurement Mechanism, decided in March 2025, which lets transmission owners book supply chain capacity earlier than they could before. For a contractor the consequence is that some equipment on a package will already be ordered or reserved before the tender is issued, and some will not.
When the lead time is longer than the gap between award and the window, someone has to commit before the contract does. Where the client has bought the equipment and will free-issue it, its delivery is a client date, and NEC4 clause 31.2 expects the programme to show when the Contractor needs it. Where the contractor must place the order within weeks of award, design has to be frozen far enough to order against, which makes it a pre-construction planning problem before it is a delivery one. Either way, the tender programme should say which case applies and show order, manufacture, factory acceptance test and delivery as separate activities rather than one long bar.
What evaluators test in an industrial tender programme
Industrial clients read a tender programme for the few things that decide whether the job can be done on their asset. Four checks separate a programme written for the site from a generic one.
The windows are fixed and dated
Every outage or shutdown named in the tender documents appears as a constraint on its own dates, with the work that depends on it tied in by logic. Where the documents give no dates, the programme states the assumption and the bid prices the risk of a later window. A programme that draws the outage as ordinary work, free to slide with everything else, suggests the bidder has not understood the asset.
Deliveries have float to the window
Long-lead items run from order to site, and the programme shows how much time sits between each arrival and the window it serves. Where that float is thin, it names the fallback, which is usually the next window, and says what the fallback does to Completion. The figure an evaluator is looking for is not a long lead time. It is the margin between the delivery and the outage.
Commissioning is planned as work
Completion on an industrial job is rarely the end of construction. It is the point at which the client’s operators take the plant, after pre-commissioning, energisation or wet testing, performance tests and the handover of documents. A tender programme that ends at mechanical completion, with commissioning left as a milestone, has left out the part of the job the client worries about most.
Live-site rules are in the durations
Permits to work, isolations, escorted access and restricted hours all slow the work on an operating site, and where the site falls under the Control of Major Accident Hazards Regulations none of them is negotiable. The durations should show it. Civil or mechanical work programmed at greenfield speed reads to an operations-led panel as a bidder who has not worked on a live site.
Under NEC4, the tender programme becomes the baseline
Once the contract is signed, the tender programme is usually the starting point for the first programme submitted for acceptance, and NEC4 asks that programme to carry the things industrial work depends on. Clause 31.2 requires it to show the order and timing of the work of the Client and Others as last agreed with them or as stated in the Scope, and the dates when the Contractor will need access to a part of the Site if later than its access date, together with Plant and Materials and other things the Client is to provide. Outages, free-issue equipment and the operator’s own work all sit inside those words.
The allocation of risk then follows the documents. If the outage dates are written into the Scope and shown on the Accepted Programme, and the client cannot give the outage when promised, the contractor has a route to a compensation event, typically under clause 60.1(2) for access or 60.1(5) where the Client or Others do not work within the times shown on the Accepted Programme. If the window was never written down, it is much harder to show that a lost outage is the client’s risk. Our guide to how the first programme gets accepted under clause 31 covers the acceptance itself, and the tender stage is the cheapest point at which to get the outage dates into the documents.
The author’s view
I would draw the client’s calendar before drawing any of the work: every outage, shutdown, seasonal restriction and client date the tender documents give, and a note against each one they leave out. The work goes in afterwards, and the order dates for long-lead equipment come out of the backward pass from the windows rather than the forward pass from award.
A programme built the other way round, from award forwards with the windows fitted in at the end, can look identical on the page. The difference shows the first time a supplier slips, because only one of the two told the client at tender stage that a year was at stake.
Summary
The money in UK industrial construction for this regulatory period is large and mostly settled: £104 billion for water in AMP8, £28.7 billion of upfront investment in RIIO-3, and a run of carbon capture, nuclear and steel projects past their investment decisions. Most of it will be spent on assets that keep running, through frameworks and call-offs, and much of it under NEC4.
Industrial construction tenders that win this work show the client’s windows as fixed dates and tie the long-lead equipment to them with float an evaluator can see. Commissioning appears as work, not as a milestone. Under NEC4 that programme becomes the baseline for delivery, so the care taken at tender is the same care that protects the margin later.
FAQ
What counts as an industrial construction tender in the UK?
Any tender for construction or engineering work on an operating industrial asset, such as water and wastewater treatment, electricity and gas networks, process plant, carbon capture, nuclear or heavy manufacturing. Most of it is let by utilities and regulated companies through frameworks and call-offs, and since 24 February 2025 most public buyers and utilities outside the devolved Scottish regime have procured under the Procurement Act 2023.
How much is being spent in AMP8?
Ofwat’s final determinations of December 2024 allowed £104 billion of expenditure for the water companies of England and Wales over 2025 to 2030, in 2022/23 prices, against £62 billion in the previous period. In March 2026 the Competition and Markets Authority added £463 million for the five companies that challenged their settlements. Delivery runs through capital frameworks that are now calling off work.
What is RIIO-3?
RIIO-3 is Ofgem’s price control for electricity transmission, gas transmission and gas distribution, running from 1 April 2026 to 31 March 2031. Its December 2025 final determinations approved £28.7 billion of upfront investment within a wider pipeline of around £90 billion. The gas distribution companies have appealed to the CMA, and electricity distribution stays on RIIO-ED2 until March 2028.
Why do outage windows matter so much in an industrial tender programme?
Because the client owns them and the contractor cannot move them. If equipment arrives or installation finishes after a window closes, the connection waits for the next one, which on a transmission connection can be a year away. Evaluators look for windows fixed on the programme as dated constraints and for long-lead deliveries that reach site with float to spare.
Does the Procurement Act 2023 apply to water companies?
In England and Wales, generally yes. The Act covers utilities, including private utilities that carry out a utility activity such as water supply under special or exclusive rights, and it replaced the Utilities Contracts Regulations 2016 from 24 February 2025. Devolved Scottish contracting authorities remain under the Scottish rules, so the position in Scotland needs checking separately.
About the author
Roman Bazelchuk is the Founder of NEC Planning Solutions Ltd, a UK project planning and controls consultancy supporting contractors with NEC programme compliance, compensation event assessments and live project controls. He is an NEC Accredited Project Manager and holds the APMG Project Planning and Control qualification, with a BEng in Mechanical Engineering and postgraduate training in Planning and Control.
NEC Planning Solutions provides contract-aware planning support through a QA-governed delivery model, helping project teams keep programmes accepted, current and commercially useful from tender through to live delivery.
Pricing an industrial tender around an outage window?
NEC Planning Solutions builds tender programmes for industrial packages that show the client’s windows and the long-lead deliveries as logic an evaluator can test, and that carry through to acceptance under NEC4. Send the tender documents and we will tell you where the programme is exposed before the bid goes in.
