Gemini System

Learn about this suite of online applications which are used for managing the transport of gas through the transmission network.

What is the Gemini System?

The Gemini System is a suite of online applications for managing the transportation of gas through the National Transmission System (NTS) in Great Britain.

These online applications are used for:

  • Capacity Management (Entry and Exit Capacity)
  • Capacity Trading
  • Commercial Balancing
  • Invoicing (Capacity and Energy Balancing)

Gemini Entry and Gemini Exit

The Gemini System is made up of Gemini Entry and Gemini Exit.

Gemini Entry is used for:

  • all Entry Capacity related activities to ensure you have booked the right amount of space to bring gas onto the NTS
  • all Energy Balancing activities which is the amount of gas you intend to flow in and out of the NTS

Gemini Exit is used for:

  • all Exit Capacity related activities to ensure you have the right amount of space booked to bring gas off the NTS through one of the exit locations including the Distribution Network (DN) offtakes

The Gemini System is owned by National Grid and Xoserve are responsible for managing and operating the System on their behalf.

Who is it for?

The Gemini System is available to our Data Services Contract (DSC) customers. This includes Shippers, Network Operators, Allocation Agents and Traders.

What Gemini Entry/Gemini Exit will do for you

Depending on your role in the industry, you can use Gemini Entry/Gemini Exit to:

Purchase Gas Capacity (Entry/Exit)
Check your organisation's Gas Capacity entitlement
Trade Gas Capacity with other organisations
Validate your Capacity Invoices
Sell Capacity back to National Grid
Register a Gas Nomination or Renomination at a location (Entry/Exit/interconnectors)
View measurements/allocations to see the quantity of gas deemed to have flowed through a location

For more detailed information on what you can do with the Gemini System, please download our Gemini User Role Descriptions.

Applying for access to the Gemini System

Gemini works on a role-based system, with each User ID given roles relevant to the duties they need to perform on the system.

You’ll need to determine your User role by reading the Gemini User Role Descriptions.

You’ll then need to contact your Local Security Officer (LSO) and ask them to return a Security Access Request Form.

Your LSO will need to request the:

  • creation of your User IDs
  • required roles for your ID

Your LSO is responsible for all account administration including:

  • creations and deletions
  • permissions and roles
  • password resets

If you’re unsure who your LSO is, please raise a support request.

How to log in to the Gemini System

The Gemini System application is only supported by Internet Explorer 11 (IE11).

The Gemini System requires the installation of:

As the Gemini System uses the Citrix application to run, two User IDs are needed:

  • one ID is used to log in to Citrix
  • one ID is configured and used for Gemini

Contingency access via XP1

The Gemini System should be accessed via Information Exchange (IX) – if it’s not possible, we provide an XP1 back-up process, using a token and the software below.

The software for accessing XP1 was updated in October 2020.

To access Gemini via your XP1 token, you’ll need to install the updated software:

Download the updated Gemini XP1 Contingency User Guide for help with the installation.

You can find more detailed information on our Gemini System Contingencies webpage.


Gemini maintenance windows:
Monday to Friday 3:15am - 4:15am 
Sunday 3:00am - 5:00am

System outages are updated on our notifications webpage.

View outage notifications

Raise a support request

Please raise a support request if you have any queries regarding Gemini.

Gemini support request

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