Orkney ANM

If you have a general query about the ANM scheme on the Orkney Islands, please contact ANM.Operations@sse.com. Similarly, ANM generators can also contact ANM.Operations@sse.com to raise any issues regarding their generation, curtailment, or SHEPD equipment at the site. Please note, responses will only be addressed during normal office hours (Mon - Fri).

The website does not identify the individual status of generators. You may be partially curtailed if your zone is Amber.

The website does not identify the individual status of generators but it does monitor communications at generator sites. If there is an indication that there is a communications fault to one or more generators then the Generator Site Issues column will be red for your zone. It could be a failure in your communications equipment and you should contact your local provider.

To ensure the safe operation of the network it is divided into zones which represent constraint points in the network on account of the additional generation. The ANM system will intervene when real time information relayed back to it exceeds any of the limits at these points.

At each measurement point there are limits that inform the ANM system how to respond. These responses are set to either partially curtail one or many generators, fully curtail (stop) one or many generator, or to remove any curtailment previously imposed

The PoA is the mechanism by which the commercial arrangements are put in place to ensure the fair allocation of limited generation on the network. On the Orkney Islands, the Last in First off (LIFO) method has been used. The last generator to accept a connection offer is restricted before the first. This list of generators, ordered by their connection acceptance, is also referred to as the priority stack.

1. Loss of generator communications [Generator Site Issues = Red, action = operator to check comms]

2. A Breach of a limit on the network [ANM operation = Red or Amber no action required]

3. Loss of power to the generator site [Action = check website or call SHEPD 0800 300 999].

4. The generator may be placed out of service [ANM operation = Red no action required]

5. The associated measurement points being placed out of service [ANM operation = Red no action required]

6. The ANM system being placed out of service [Overall ANM Operation = Red no action required] 

7. Failure of SHEPD equipment that is part of the ANM system [SHEPD equipment = Red, Action = email ANM.Operations@sse.com]

A firm connection enables a generator to export power onto the electrical network without any restriction.

A managed connection is offered when it is not economically viable to provide a generator with a firm connection. This will restrict the generator from putting power onto the electrical network at certain times. This is known as curtailment and the generator will have been given a curtailment assessment as part of the connection offer that they have accepted.

Active Network Management (ANM) is a system that allows managed connections. It uses real time network information to calculate safe levels of generation for managed connections in accordance with their commercial agreements and Principles of Access (PoA).

The ANM system informs the SHEPD network operators if there are any issues with the system. Therefore, there should be no need to contact SHEPD. If you feel there is the need to contact us please check the website beforehand.

Managed connections have been offered on Orkney as an alternative to network reinforcement to allow quicker access for those generators trapped between the current network configuration and the upcoming network reinforcement.

All generators will be fully curtailed (stopped) if either of the subsea cables to the Orkney Islands fail, the ANM system may be placed out of service, or one of the main measurement points has been put out of service. A measurement point or the ANM system may be placed out of service for network management purposes.

One or more generator in the zone is being partially curtailed. This can be as a result of a breach of limit.

No generators in the zone are being curtailed.

One or more generators in the zone is being fully curtailed. This can be as a result of a breach of a limit, or a generator has failed to respond to an ANM signal to reduce its generation, or the ANM or associated measurement point has been put out of service. A measurement point may be placed out of service for network maintenance

The table distinguishes between normal expected ANM operation, SHEPD equipment failures and indications where there may be a fault with generator communications. Changes in ANM operation reflect the ANM system operating as expected.

There has been a failure of some part of the SHEPD equipment in the ANM system that affects all zones. This could be as a result of a failure in either of the communications equipment at the UK mainland subsea cables.

All SHEPD equipment related to the ANM is operating as expected.

There has been a failure of some part of the SHEPD equipment in the ANM system. This could be as a result of a failure in the communications equipment. The ANM system informs the SHEPD network operators if there are any issues, however you may want to email ANM.Operations@sse.com

The table distinguishes between normal expected ANM operation, SHEPD equipment failures and indications where there may be a fault with generator communications. Changes in SHEPD equipment reflect potential issues with the ANM system that are the responsibility of SHEPD and the ANM system is not operating as expected. SHEPD will endeavour to resolve these as soon as they can.

There has been an indication that there may be a fault with one or more generator communications. As a result the ANM responds by issuing full curtailment to the affected generator as a fail safe response. It is the responsibility of the generator to resolve these issues.

There is no indication that there is a fault with any generator communications in the zone.

The table distinguishes between normal expected ANM operation, SHEPD equipment failures and indications where there may be a fault with generator communications. Changes in Generator Site Issues reflect potential issues with the communications to one or more generator sites (which is not the responsibility of SHEPD), power loss failures to the generator or the ANM panel software failure (responsibility of SHEPD). As a result the ANM responds by issuing full curtailment to the affected generator as a fail safe response.