When a new commercial development requires an electricity connection, the work is typically split into two categories: contestable and non-contestable works.
Understanding the difference between the two is important because it affects who carries out the work, how long the project will take, and ultimately how much it will cost.
Unfortunately, the distinction is rarely clear to developers when they first start looking into a connection.
What Are Non-Contestable Works?
Non-contestable works are elements of a connection that must be carried out by the Distribution Network Operator (DNO).
These are usually works that involve direct interaction with the existing electricity network or tasks that the DNO considers critical to maintaining network integrity.
Typical non-contestable works include:
Identifying and approving the Point of Connection (PoC) to the network
Network reinforcement, if the local network does not have sufficient capacity
Any work carried out directly on the live electricity network
Final energisation of the connection
Because these works must be completed by the DNO, the developer has no choice over who carries them out.
This can sometimes create bottlenecks in a project programme, particularly if network reinforcement is required or the DNO has long lead times.
What Are Contestable Works?
Contestable works are elements of the connection that can be carried out by accredited Independent Connection Providers (ICPs) rather than the DNO.
Typical contestable works include:
Installing new electricity cables
Constructing substations
Installing switchgear and associated equipment
Excavation and reinstatement works
Developers can choose to appoint an ICP to carry out these works, which often provides greater flexibility on programme and cost.
In many cases, ICPs can deliver contestable works more quickly than a DNO, particularly on larger commercial or industrial developments.
Why This Distinction Exists
The separation between contestable and non-contestable works exists to open parts of the electricity connection market to competition.
Historically, DNOs carried out all connection work. Regulatory changes introduced the ability for accredited contractors to deliver parts of the process, giving developers more choice.
This competition has helped:
Reduce connection costs in many cases
Increase delivery capacity within the industry
Provide developers with greater control over project timelines
However, because DNOs still control access to the network itself, both parties remain involved in most projects.
Why It Can Become Complicated
Although the concept sounds simple, the boundary between contestable and non-contestable works is not always straightforward.
Different DNOs have slightly different rules around what they allow ICPs to deliver.
There are also situations where works that are technically contestable may still be delivered by the DNO due to:
Network complexity
Safety considerations
Project-specific constraints
This can create confusion for developers who are unfamiliar with the electricity connections process.
Why Early Advice Matters
For many commercial developments, the way contestable and non-contestable works are structured can have a significant impact on programme and cost.
Understanding the options early allows developers to:
Assess whether an ICP delivery model is appropriate
Identify potential programme risks within the DNO’s scope of work
Structure the project in the most efficient way
Taking advice early in the design stage can help avoid surprises later in the programme.
Final Thoughts
Electricity connections are rarely as straightforward as simply connecting a cable to the nearest network.
Understanding how the work is divided between contestable and non-contestable elements is one of the first steps in navigating the process effectively.
For developers who are unfamiliar with the electricity connections market, early guidance can make a significant difference to both cost and programme certainty.
About the author
Andy Shadwick is a utility connections consultant specialising in commercial and industrial electricity connections across the UK. He works with developers, consultants and contractors to plan and deliver new electric connections, helping projects avoid delays, unnecessary cost and long-term capacity constraints.
