Select Committee on Environmental Audit Minutes of Evidence


Supplementary memorandum submitted by National Grid PLC

Annex: supplementary questions

1.  TO WHAT EXTENT DO THE VARIOUS GENERATING OPTIONS—MICRO-GENERATION, WIND, NEW NUCLEAR ETC—REQUIRE SIGNIFICANTLY DIFFERENT INVESTMENT STRATEGIES ON YOUR PART (DEPENDING ON WHICH IS PROMOTED MOST)?

  1.1  The power flows on the transmission system are a function of the location of demand and generation across the country. To meet these power flows, National Grid is obliged to invest in the network and provide sufficient capacity to meet requirements that are stipulated in the Security and Quality of Supply Standard (SQSS). It is therefore the location of generation, rather than its type, which is the principal driver for transmission investment. Of course, certain technologies, due to the availability of their fuel or other planning issues, will tend to be associated with particular locations. If new generation displaces/replaces existing plant, then the location of the displaced generation will be equally important in determining new power flow patterns. However, assuming the pattern of plant closures/retirements will be the same for all new generation development options, then:

1.2.   Micro-Generation

  As micro-generation is likely to be installed within premises near to load it is likely to be uniformly spread across the GB system. It is therefore unlikely to trigger significant new transmission investment and may reduce the requirement to provide additional capacity to the DNO networks.

1.3  Wind

  In Great Britain, our most significant wind resources are in Scotland and offshore locations therefore potential wind generation sites are generally located away from main centres of demand. In order to transport electricity from points of generation to demand, there will be a requirement to invest in the networks in order to not only extend them to allow wind farms to physically connect, but investment will also be required in order to increase the transmission network capacity of the system to allow bulk transfers of power from the north, to the large demand centres to the south.

1.4  Nuclear

  The investment required to accommodate a new nuclear fleet of power stations is dependent upon the choice of site and location. If new nuclear power stations are equivalent in size and site to existing nuclear power stations, investment requirement should not be significant, although there may be some requirement to refurbish or replace ageing infrastructure. However, if more nuclear power stations are sited in the north, this could trigger significant investment to accommodate increased bulk power transfer on the transmission system (similar requirements to wind).

2.  IN YOUR EVIDENCE, YOU SUGGESTED THAT SOME EARLY CLARIFICATION OF HOW OFF-SHORE WIND WILL CONNECT INTO THE SYSTEM WOULD BE HELPFUL [Q465]. COULD YOU PROVIDE THE COMMITTEE WITH MORE INFORMATION ON WHAT CLARIFICATION IS NEEDED, AND ON THE SCALE OF INVESTMENT WHICH IN YOUR VIEW IS REQUIRED? [CF Q471].

  2.1  In order to meet the timescales to meet the Government 2010 renewable targets, it is necessary to bring wind farms forward on an unprecedented scale. It is expected that this can only be done by building offshore windfarms. In order to achieve this, a number of steps are required. These include legal, technical, and commercial issues. Initial clarification is needed on the regulatory regime that will operate offshore. The DTI is currently consulting on two options for regulating the offshore networks. The frameworks in which offshore transmission might be developed are a merchant (ie developer funded) approach, or a price regulated approach (funded via the GB use of system tariff). We believe that the latter approach permits additional policy choices over those available in the merchant model and these choices may be selected to facilitate, sooner than might otherwise be the case, the development of the offshore wind industry. Given the pressing nature of the Government climate change and renewable energy targets, we believe this to be an important issue that needs clarity. If a regulated route is chosen then the following steps are required; the appointment of a system operator in offshore areas, the allocation of offshore transmission owner licencees and a number of changes to existing industry licences and codes to ensure that the appropriate legal and commercial framework is in place. To meet the Government 2010 targets, these issues will need to be resolved before the physical construction work of building offshore transmission networks can actually begin. This work may in itself take a number of years to complete and the timetable which was set out in the Government consultation on offshore wind networks may need to be revisited in order to allow the 2010 targets to be met.

  2.2  At present the security standard (ie the inherent redundancy designed into the network) for the offshore connections to wind farms has not been formalized. Preliminary design work by National Grid and engineering consultants acting for the DTI suggests that there could be substantial benefits in adopting different security criteria to those used onshore. Such changes would reduce network costs by reducing the number of connection cables and hence the backup capacity that is needed in onshore overhead line networks. Such designs should provide connection availability acceptable to wind generators and would not significantly affect the supply reliability experienced by GB consumers.

  2.3  The appropriate form of the offshore network security standards depends on the allocation of responsibilities for design and operation of the offshore networks and this will in turn depend on the outcome of the DTI's consultation on how offshore networks should be regulated. If the establishment and operation of the offshore networks (and the losses, constraints and unavailability that result) are the responsibility of the offshore generators they serve then the scope of security criteria could be limited to just the interface with the onshore network. If, on the other hand, responsibility for design, build and operation are divided between a price controlled transmission owner and the GB system operator then aspects of the design of offshore networks will need to be specified more explicitly.

  2.4  The most comprehensive study of the likely cost of offshore networks has been undertaken by Econnect, consultants acting for the DTI. They suggest that for the sites being considered in the three offshore strategic areas, connection capital costs would range from £130/kW to £250/kW depending on distance of the wind farm from the shoreline. For a total Round 2 offshore development of 5GW, they suggest total capital costs will be in the region of £750 million.

  2.5  In terms of the onshore network costs to accommodate offshore wind farms, we are presently progressing a number of onshore connection applications from large offshore windfarms. Due to the defined strategic areas for offshore wind farms, the connections tend to be clustered and connected at similar locations (in the North West, North East, The Wash & the Thames Estuary) on the National Grid network. The network investment required in these areas are interactive with investments required to accommodate new Combined Cycle Gas Turbine (CCGT) power stations as well as, in the north, investments needed to accommodate the transfers resulting from wind generators in Scotland. Therefore, the investment figures provided below consider the impact of all the potential generation connecting in a give area.

2.5.1  North West

  We have received interest (either signed connection agreement or application in progress) to connect approximately 1.5GW of wind generation in this area. This will require major reinforcements in the Heysham area to accommodate this volume of wind generation. The cost of these reinforcements are in the order of £150-200 million. However, a number of these reinforcements are also required to accommodate the additional power flows from Scotland and discussions are ongoing with Ofgem on how to take these reinforcements forward.

2.5.2  North East

  We have received interest to connect approximately 0.75GW of wind and approximately 3GW of CCGT generation seeking to connect in the North East. If all of this generation was to connect, the cost of the additional reinforcement would be in the order of £150 million.

2.5.3  The Wash

  We have received interest to connect approximately 1.5GW of wind generation and approximately 1.3GW of CCGT generation seeking to connect in this area. The transmission network can accommodate approximately 1.5GW of generation before any major expenditure is triggered. However, if all of this generation was to connect, it would trigger requirements for additional investment in the network at a cost of £150 million.

2.5.4  The Thames Estuary

  We have received interest to connect approximately 1.3GW of Wind generation and interest to connect a further 2.5GW additional generation in this area. If all this generation was to connect, the cost of the additional reinforcements would be in the order of £200 million.

2.5.5  Wales

  We have received interest to connect approximately 1GW of wind generation (onshore and offshore) and interest to connect a further 4.8GW CCGT in this area. If all this generation was to connect, the cost of additional reinforcements would be in the order of £200 million.

2.5.6

  In total we have received firm interest to connect (ie applications to connect) some 6GW of wind generation by 2011 and interest to connect a further 11.6GW of other types of generation within the same areas. If all this generation was to proceed, the cost of additional reinforcements would be in the order of approximately £850-900 million.

2.5.7

  It should be noted that there may be additional projects which as yet we are not aware of and so these costs could eventually increase.

  2.6  However, it is unlikely that all this generation will proceed, and, where it does eventually proceed, experience with generation projects tells us that it is often not to the timescales indicated in initial applications. There could be a number of project specific reasons for this such as planning issues, financial issues etc Therefore, if we were to undertake all of this investment, it is very likely that a significant proportion would not be utilised and National Grid could have a significant number of stranded assets. To avoid this, we require users to make financial commitments in the form of indemnities (called Final Sums Liabilities). These indemnities ensure that if a network investment is initiated to accommodate a new network user, and that user subsequently terminates the connection agreement before completion and payment of transmission charges, then the user will pay for any investments that would otherwise become stranded. National Grid, by requesting developers to provide this financial commitment, obtains a clear indication that the user believes their project will proceed.

3.  YOU REFERRED TO THE INTRODUCTION OF COST-EFFECTIVE CHARGING AND THE EXTENT TO WHICH THIS IMPOSED EXTRA COSTS ON REMOTE GENERATION [QQ467FF]. CAN YOU PROVIDE SOME INFORMATION ON THE SCALE OF SUCH EXTRA COSTS?

  3.1  National Grid recovers the cost of network investments through the Transmission Network Use of System (TNUoS) tariff. The tariff is constructed such that the difference in charges between zones reflects the annual cost of financing the associated network capacity between those zones. For generation and half-hourly metered demands, the charge is levied on a measure of the capacity required by that generator or demand in that year.

  3.2.  The network investment costs needed to accommodate wind generators in the North of Scotland and transport the power to the major load centres in England were assessed in a recent study by the three transmission licensees. (See the Renewable Energy Transmission Study undertaken for the DTI's Transmission Issues Working Group). This analysis demonstrates the cost-reflectivity of this tariff, in the order of £250/kW. The annual financing cost of such an investment, at regulated rates of return, would be circa £20/kW/yr. This matches closely the difference between the tariff zone for the North of Scotland and that of the Midlands & South East.

4.  DURING THE COMMITTEE'S RECENT VISIT TO DENMARK, REPRESENTATIVES FROM THE DANISH COMPANY E2 WHO ARE INVOLVED IN THE LONDON ARRAY PROJECT RAISED THE ISSUE OF THE FINAL SUMS LIABILITY OF £100 MILLION ASSOCIATED WITH THE PROJECT. THEY SUGGESTED THAT THEY COULD NOT PROVIDE SUCH A GUARANTEE BEFORE OBTAINING PLANNING CONSENT, AND THAT THIS WAS HIGHLY LIKELY TO DELAY THE PROJECT. CAN YOU PROVIDE MORE BACKGROUND INFORMATION ON THE FINAL SUMS LIABILITY AND ITS IMPACT ON PROJECT IMPLEMENTATION IN THE LIGHT OF THE DANISH COMMENTS? [THIS QUESTION IS BEING PUT TO OFGEM ALSO.]

  4.1  As stated above, some 4.8GW of generation have expressed interest in connecting in the Thames Estuary. If all this generation was to connect, additional reinforcements would be triggered at a cost of approximately £200M. However, if we undertook all this investment and all the generation in this area did not proceed, it would result in un-necessary investment (stranded assets) and a cost which the industry as a whole and consumers could potentially be exposed to. Therefore, to ensure that a party that triggers the need for the investment only does so once they are committed to progressing their project to completion, we require the user to provide an indemnity to cover any costs incurred if they terminate the connection agreement and do not complete their project. In the case of London Area, all parties seeking to connect in this area have been requested to provide final sums liability in proportion to the works that they trigger. This mechanism therefore fulfils two purposes:

    4.1.1  It indemnifies National Grid against the project specific risk of a developer failing to complete its project and our investment becoming stranded and the assets unused.

    4.1.2  It forms part of the evidence National Grid uses to demonstrate to OFGEM that projects are required and therefore should ensure that we should receive appropriate funding though our price control mechanism.

5.  IN YOUR MEMORANDUM, YOU SUGGEST THAT A GROWTH IN MICRO-CHP MIGHT ACTUALLY DELAY THE NEED FOR GRID REINFORCEMENT. BUT TO WHAT EXTENT CAN THE LOCAL DISTRIBUTION NETWORKS THEMSELVES COPE WITH A SUBSTANTIAL GROWTH IN MICRO-GENERATION? OR IS SUBSTANTIAL INVESTMENT REQUIRED TO PRODUCE MUCH "SMARTER" LOCAL SYSTEMS?

  5.1  National Grid does not own or operate Distribution Networks within Great Britain; rather our focus is purely on the ownership and operation of transmission assets. It may therefore be more appropriate to address this question directly to a Distribution Network Operator who would be able to provide the Committee with a more complete response to this question.

6.  IF WIND POWER AND MICRO-CHP WERE TO SUPPLY PERHAPS 20% OR MORE OF ELECTRICITY GENERATED, TO WHAT EXTENT WOULD THEY BE IN COMPETITION WITH NUCLEAR FOR SUPPLYING BASELOAD CAPACITY? IN SUCH CIRCUMSTANCES, WOULD THE INFLEXIBILITY OF NUCLEAR POWER ADVERSELY AFFECT THE FINANCIAL VIABILITY OF THESE OTHER FORMS OF GENERATION? DOES NUCLEAR POWER IMPOSE ANY OTHER COSTS ON OTHER FORMS OF GENERATIONFOR EXAMPLE, IN TERMS OF THE NEED TO MAINTAIN SUFFICIENT SPINNING RESERVE?

  6.1  Our understanding is that the observed inflexibility of current nuclear generation may be a characteristic of those particular designs and may not be a feature of future reactor designs. (Others will be more qualified to provide information on this). The inflexibility of current nuclear generators has meant that they prefer to operate at a constant output, delivering baseload power. Given the current daily/seasonal demand cycles, the national minimum load is approximately 40% of peak demand. This means that there is at least 25 GW of base load opportunity. For comparison, there is approximately 12GW of existing nuclear capacity. If wind power and micro-CHP were together providing 20% of electricity requirements, then on average they would produce circa 8 GW (although with considerable variability around this mean). This would suggest there would be ample opportunity for nuclear generators to continue to operate in an inflexible way. While significant domestic CHP is unlikely to operate at times of low electricity demand (because there is less need for heat) it is possible that a large proportion of the wind generation could be operating on a windy low demand day (although these are much less frequent than windy winter days). However, using the above figures suggests that nuclear would only need to be curtailed from full output if more than 17GW of wind operates at minimum load.

  6.2  If there is insufficient flexible generation or load to meet demand cycles, plant breakdowns and frequency control requirements then additional costs would need to be incurred to bring on flexible plant. At present there is adequate flexibility throughout the year and the inflexibility of existing nuclear generation can be accommodated without significant cost. On this basis we do not see how current nuclear inflexibility in particular, would impact on the financial viability of any other generation types.

7.  SOME ORGANIZATIONS AND INDIVIDUALS HAVE ARGUED THAT THE CURRENT INCENTIVE STRUCTURE FOR DISTRIBUTION NETWORK OPERATORS (DNOS)—WHICH IS LARGELY BASED ON ASSET VALUES—FAILS TO PROMOTE ADEQUATELY THE DEVELOPMENT OF ENERGY SERVICES; AND THAT THAT THE UK LOST AN OPPORTUNITY TO ADDRESS DEMAND MANAGEMENT MORE RADICALLY BY FAILING TO ALLOCATE METERING TO DNOS. WHAT IS YOUR VIEW?

  7.1  National Grid does not own or operate electricity Distribution Networks within Great Britain; rather our focus is purely on the ownership and operation of transmission assets. It may therefore be more appropriate to address this question directly to a Distribution Network Operator who would be able to provide the Committee with a more complete response to this question.

13 January 2006



 
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