What do I need to do to Re-Power my Generating Facility?

Whether your connection conforms to G59, G99, or a combination of the two, you will need to submit a new G99 application, which you can find on our Connections – useful documents page. We can then review the connection and work with you to determine the actions required to Re-Power your generating facility.

Will my complete Generating Facility need to conform with the latest version of G99?

Once we receive your application, we will work with you to understand the scale of the Re-Powering. In some instances, some or all components of a generating facility may not need to conform to G99, depending on the scale of the changes and characteristics of the new components compared to those they are replacing. However, in a Re-Powering project it’s more than likely that the characteristics of the new components may have a vastly different impact on our network, therefore requiring most, if not all components in the Generating Facility to conform to G99.  This may include where new components have a different impact on fault levels and harmonics to the network. Therefore, we need to make sure that the existing connection is fit for purpose and the network remains within statutory limits.

What happens to my capacity?

If you have an existing connection, then applying to Re-Power your generating facility will not automatically impact your contracted capacity. The import and export capacity stated in your current connection agreement should remain yours as long as you are still able to comply with the terms governing that connection agreement. If the changes you want mean you can no longer comply with the terms of the connection agreement, we will discuss the impact of the proposed changes with you when we receive your application.

What charges could my application incur?

A Re-Powering application may incur some or all, of the following charges:

  • Connection Offer Expenses (COE): As we’ll need to assess the impact of any changes you make to your generating facility on our network, COE fees will be applicable where your connection is at 11kV (HV) or above. Further information can be found on our Connection Offer Expenses
  • Witnessing of Commissioning works: It’s likely that we will need to witness some or all changes you make to your generating facility, especially in relation to any new components you intend to install or any protection changes. Any witnessing requirements will be discussed with you and detailed in your Connection Offer.
  • Reinforcement costs: in some instances, including in like-for-like replacements, reinforcement works may be required to accommodate the new components, such as where the new components have a higher fault level contribution. In which case, any reinforcement works may be apportioned with yourself and detailed in your Connection Offer.
  • Transmission Impact Assessment (TIA): A TIA may be required where you are connected in a constrained portion of our network and either:
    • You request an increase in your current contracted capacity; OR
    • We determine that reinforcement works are required due to the increased fault level contribution of your new components.

Further information on this process can be found on our Generation Connection Processes page.

Where you make no changes to your current contracted capacity and your connection is not in a constrained portion of our network, then a TIA will not be required.

For queries on re-powering, please contact your Account Manager or commercial.contracts@sse.com