This page includes information about the connections offer process. We’ve split the process into five parts, each of which contain step-by-step guidance on roles and responsibilities. There are also links to relevant resources, but if you can’t find what you’re looking for then please contact us.
If you’re a new customer applying for a contract with us for the first time, or an existing customer applying for a new project, you’ll need to have a pre-application conversation. Here’s how:
If you already have an existing contract, pre-application conversations held ahead of a Modification application, are likely to be brief and held with the ESO Contract Manager only, depending on the change to the contract.
2. Application submissionYou will need to submit an application form that relates to the type of contract you’re looking for through the ESO Connections Portal.
By exception and until June 2023 manual applications may be submitted in certain circumstances, and will follow the process below:
Following application submission:
The process is the same for new applications and modifications to existing agreements. The only difference is the application form.
3. CUSC offer periodOnce your application clock has started, we have three months to issue your connection offer. This is what’s happening during that time:
We’ll make sure you’re kept up to speed throughout the offer period by your ESO Connections Contract Manager.
4. Offer review/ signing periodOnce you’ve received our contract offer, you have three months to review it and ask any questions. These are the steps in this part of the process:
This process assumes the offer is signed but there are other options available to you. You could let the offer lapse or refer it to Ofgem. In some cases, we may issue a re-offer.
5. Continuous engagementOnce you become a contracted party we’ll assign you an ESO Connections Contract Manager for the duration of your project. This includes pre-commissioning and post-commissioning. Your ESO Connections Contract Manager is your primary contact for any queries or changes you wish to make to your agreement with us. You will also have contacts within the TO who can help you with anything relating to development, construction or delivery of your project.
What to expect in your offerOur interactive PDF will give you a good overview of what you can expect to see in your contract offer from us. It includes high level explanations of each of the offer elements as well as links to relevant resources.
How to complete your applicationThe PDF also gives you helpful guidance on how to complete your application. If you need more help, then one of our Connection Contract Managers will be happy to talk you through the process.
Connection and use of System code (CUSC) Customer GuidesCustomer guides give an overview of processes or concepts within the CUSC. These guides are designed to provide detail and context to the contents of the CUSC.
Customer SecurityThe customer security guides step through the different elements and concepts of both the CMP192 and Final Sums methodologies.
In addition to the guide the links below contain templates for various forms of security:
The purpose of the guidance document is to set out the detailed process that the ESO will follow when Interactivity is been identified and notified by the Relevant Transmission Licensee that two or more offers have become interactive with each other.
The process set out in the document is consistent with the process that will be followed by the other network operators within Great Britain.
This high level guide covers your connection process from start to finish. From your application to changes to your contract, compliance and commissioning, and finally connection or disconnection.
Got a question? Search our bank of frequently asked questions.