Grid Code under BETTA

Comments by Innogy plc

Grid Code under BETTA

Comments by Innogy plc

The comments below are made on behalf of Innogy plc, Npower Limited, Innogy Cogen Trading Limited, Innogy Cogen Limited, Npower Direct Limited, Npower Northern Limited, Npower Yorkshire Limited Npower Northern Supply Limited, Npower Yorkshire Supply Limited.

The legal framework for the GB Grid Code

A single ownership of the Grid Code would seem necessary to maintain consistency and to minimise the administrative burden. However, the effectiveness of this model would depend on the relationship between the TO and SO. Users should not be subject to “pass-through” obligations from the TOs to SO without an effective route for considering fully all compliance issues.

We hold to the view that the data the SO requires from a User must be specified within the Grid Code. The Grid Code should also identify any third parties to which this data may be passed. Confidentiality and associated safeguards must also be carefully addressed. This might be achieved by placing a specific Licence obligation placed on the SO and any licenced party who may be a recipient.

The E&W Grid Code has been subject to continuous and extensive change in line with the development of the commercial trading arrangements since 1990. Since these changes do not appear to have been incorporated in the Scottish Grid Code to the same extent it would seem that the E&W Grid Code would provide the best basis for a GB Grid Code.

Differences between the existing Grid Codes

Composition of the Grid Code Review Panel

The Grid Code review panel coverage of any technical specification and recommendation argues for the TOs, who are likely to be the main originators of change, to have representation on the Grid Code Review Panel. However, it is important that the TO and SO representation is balanced by the views of other industry participants. We would suggest that this balance would be best struck by the TO/SO representation not exceeding , say, 25% of the Panel members.

We do not consider it either necessary or appropriate for there to be specific representation for Users in Scotland and E&W, given the proposed cross-industry representation and the general unification of requirements in the GB Grid Code and other Codes. Similarly, whilst we would support additional generator representation on the Panel, it is more important that this is drawn from individuals who are knowledgeable about the issues and have a specific interests, rather than being based on employees of companies which have assets connected at any specified voltage.

The interaction of issues concerning generation connected at what will be defined as “transmission” voltages and embedded in the distribution system makes it desirable that there should be cross representation between the Distribution Code Panel and the Grid Code Panel. More radically Ofgem/DTI may contemplate the advantages of merging the Distribution Code and Grid Code Panels into a single Panel, and even merging the two Codes into a single Code that might be termed the “Network Code”. Although there will be significant differences to the electricity market, there are precedents for this approach.

Document structure

As Ofgem/DTI has noted the Grid Code is in reality a collection of Codes. Given the wide scope of aspects and timescales covered by the Grid Code this would appear a tried and tested structure. Since the wording of the Grid Code must be capable of precise legal interpretation if an ‘introductory section’ were to be included then it should be made clear that it does not constitute a part of the Code. For instance it should not include any element of ‘interpretation’ or ‘guidance’ of the Grid Code.

Balancing codes

Whilst we would support the proposal that the Balancing Codes in E&W should form the basis of a GB Grid Code, it will need to be noted that these only apply to generating units greater than 50MW, or if it is a BM participant. Operational constraints that apply to generating units that are either BM Units less than 50MW or are not BM Units (i.e. SVA registered), need to be addressed in the Distribution Code. In some case there may be conflict between the SO’s requirements for this category of generation and the DNO’s requirements. Where such a prospect exists then this should be resolved between the relevant Network operators and enshrined in the appropriate Code. This prospect, especially at a time when Government policy is leaning towards an increasing quantity of embedded generation, argues for combining the Grid Code and Distribution Code into a single Code, or a single collation of Codes.

Ancillary services

The only “mandatory” ancillary services remaining in E&W are the provision of reactive power and frequency response. The reactive capability of generating units is important to the stability of the local network and is addressed in the Grid Code for generation over 50 MW (or over 100 MW if the generation is awarded Licence Exempt status). At distribution voltages the DNO will impose criteria commensurate with the configuration of the local system. Our view is that the same criteria and thresholds should apply in Scotland.

In the case of frequency response, a market arrangement for the provision of this service is long overdue. The requirement for this service and the ability of generation to provide it is not a function of the size of the generator or its voltage of connection but of the technology employed. As an interim arrangement NGC’s Grid Code conditions may apply to existing generation over 100 MW in Scotland. However, this should be against a programme of introducing a market in frequency response based on a minimum requirement specified in the Grid Code, and commercial arrangements established in a competitive environment.

Planning codes and data submission

At present there is a paucity of planning information for Scotland. The relative lengths of the respective Planning Codes starkly illustrate this. The same comment might also be applied to the DNOs. In accordance with the objective of generally promoting competition in Scotland we would suggest that the E&W data requirements should be adopted in Scotland. Similarly, if the market arrangements are to be merged the same timescales should be adopted in Scotland for the provision of “Week 24” data.


We would support the Ofgem/DTI proposal that the GB Grid Code should not include any further special provisions for interconnector BM Units

MW levels for data requirements

We would not support different definitions for small, medium and large power stations depending on the TO area in which the generation was located. Whilst the information requirement that were adopted in E&W at NETA Go Live were consistent with pre-NETA obligations, it must be remembered that there are also information requirements on DNO connected generation and between DNOs and NGC. Our proposal would be that this hierarchy is replicated in Scotland. This might be achieved by applying the same information requirements to all generation over 50 MW, but replicating in the GB Grid Code the Distribution Code information requirements for generation less than 50 MW that is connected at a transmission voltage.

The same approach could be taken for generation despatch.

Operating codes

Safety considerations must always be paramount, and special care will need to be taken during a period of change. Safety considerations will also be a function of the nature of the local system but in the longer term it may create a safer environment if there is a common approach to Safety Coordination across the system.

Current ongoing modifications

The generic provisions for connections is also subject to development in the E&W Grid Code. These provisions include the connection of wind farms and other renewable generation. Separate work is in progress on modifying the Scottish Grid Code in respect of renewable generation. It would be helpful to the implementation of BETTA if these programmes could be merged as soon as possible.

Other issues

An anomaly highlighted by combining the Scottish and E&W Grid Codes is the treatment of generation connected to the Scottish 132kV transmission voltage. Whilst maintaining a separate Grid Code and Distribution Code may simplify the connection requirements for different categories of generation, it is confusing and inefficient to subject Scottish 132kV connections to the GB Grid Code whilst E&W 132kV connections are subject to the GB Distribution Code. We have suggested a possible remedy to this above, but the general principle that should be adopted is that the requirements on generation should be a function of the size of the generation, rather than the voltage of connection. There may be a need to cover any local circumstances in the bilateral agreement with the network owner.

7th February 2003Page 1 of 4