Energy Networks Association (ENA) – Written evidence
Energy Networks Association (ENA) represents the “wires and pipes” transmission and distribution network operators for gas and electricity in the UK and Ireland. Our members control and maintain the critical national infrastructure that delivers these vital services into customers’ homes and businesses.
ENA is responding to this inquiry on behalf of its electricity members and in support of their own individual submissions and the submission of the E3C’s Electricity Task Group.
Since privatisation in 1990 the UK’s energy networks have a strong track record of investing in safe and reliable energy infrastructure. The overall reliability of the transmission system was consistently high over the last price control period (2007-13) and well over 99.99% across all three electricity transmission networks in 2012-13. In the distribution network, the chance of a customer experiencing an interruption (that is, how often the lights go out) to their electricity supply reduced by 17% between 2002-03 to 2010-11. Over the same period, the time that the average customer is without power (in other words, how long the lights are out) has fallen by 25%.
ENA and its member companies work closely with DECC, the Energy Emergencies Executive (E3C and its Task Groups), other government departments and Ofgem to ensure the continued resilience of electricity networks and maintain and improve the industry’s response to emergency situations to ensure that customers continue to receive an extremely high level of service.
ENA and its member companies support national fora on resilience, interdependencies and climate impacts, including the Cabinet Office Infrastructure Security and Resilience Industry Forum and the Defra sponsored Infrastructure Operators Adaptation Forum.
Distribution Network Operators also attend Local Resilience Forums (LRFs) and ENA attends the LRF chairs meetings. Risk documents covering the main electricity network risks are issued to LRFs and companies are in regular communication with them. This engagement helps to ensure good communications with the civil resilience community
The main threats/challenges for the country’s electricity networks are considered to be due to severe weather, including flooding and the impact of climate change in the medium/long term. A recent report published by The Committee on Climate Change praised UK electricity distribution and transmission companies for implementing comprehensive strategies to safeguard the resilience of their networks to climate change.
Weather impacts are generally more prevalent on Distribution Networks which are more prone to wind-blown material, falling trees and other weather impacts.
Network Design
UK electricity networks are designed, constructed and operated to very high standards and this results in supply reliability for customers which are comparable to the best in the world.
These design standards provide increasing levels of resilience as the demand on a particular part of the network increases. This principle helps to ensure that where the network supplies a greater number of customers increased redundancy is built to provide a more robust network. These levels are set out in industry codes supported by regulation.
Network owners face a dual challenge from potential climate change impacts:
and
Finally, Network Operators must be ready to respond to the challenge of a technical failure or part failure of the grid system or shortage of generation leading to either a “Black Start” or the need for Rota Load Disconnection under The Electricity Supply Emergency Code.
The serious incidents of flooding in the South Midlands and South Yorkshire during the summer of 2007 highlighted the potential vulnerability of electricity substations to major flood incidents from current levels of flooding.
Following the 2007 floods an ENA Task Group was set up to produce a common approach to the assessment of flood risk and develop target mitigation levels that could be subject to cost benefit assessments. This was enabled by the great improvement in information on flood risk in recent years.
The Task Group comprised representatives from Networks Companies, DECC, Ofgem, Environment Agency, Scottish Environment Protection Agency, Met Office and the Pitt Review Team. This group developed an industry Engineering Technical Report (ETR) 138, Resilience to Flooding of Grid and Primary Substations.
The report was accepted by E3C and companies are now undertaking a programme of work to improve substation resilience to flooding. This programme was agreed by Ofgem when they set the current allowances for Transmission and Distribution companies as part of the regulatory control periods. The respective allowances are published and expenditure monitored on an annual basis.
This approach is held up as an exemplar by the Defra led Infrastructure Operators Adaptation Forum and details are published on the Institute of Engineering Technology web site.
ETR 138 is based on current flood risk and also provides an allowance for climate change based on latest evidence.
When the ETR was developed there was insufficiently accurate information available on surface water flooding to justify expenditure on a protection programme. However, information has recently improved and the Task Group was reconvened to assess this in conjunction with EA, SEPA, DECC and Ofgem.
As a result of this review, ETR 138 will shortly be re-issued with guidance on protecting sites from surface water flooding. Again, this will include an allowance for climate change impacts.
All flood protection is due to be complete by 2023 with higher risk sites being completed early in the programme.
In the latest floods, no major electricity substations were adversely affected and a number of sites were protected from imminent flooding.
ENA and members have sponsored ground breaking research on climate change impacts and have developed a report in response to the requirements of the Climate Change Act.
The report covers:
A task group was assembled including DECC, Ofgem, Defra, Environment Agency, Met Office and other organisations.
Electricity Network Companies across the UK have experience in operating in a range of weather conditions and have always used the latest information when considering current threats and potential climate change impacts. Most recently companies have worked with the Met Office on ‘EP2’, a report on up to date information and predictions about the impact of climate change.
This latest report which took the threats from climate change projections and assessed the impacts on energy networks companies was a groundbreaking initiative that brought climate science closer to business applications. This was the first project sponsored by an entire sector to review the specific impacts of climate change on their industry.
Supported by climate scientists, experts from the industry worked together to understand their precise requirements and developed practical applications and business strategies for a changing world.
Further work has since been commissioned with the Met Office to build a risk model that quantifies the relationship between climate and network faults, and also the vulnerability and exposure of the network to these faults.
The main impacts on electricity networks from the current climate change projections are:
At present there is no firm climate change evidence to support increased intensity of wind or ice storms, both of which can cause extensive damage to overhead electricity networks.
The report considers each component of Transmission and Distribution Systems and uses current industry techniques to calculate the effects of climate change to 2099.
The greatest risk is from flooding from rivers, the sea and surface water and this risk is being brought under control by the flooding resilience work discussed above.
The ENA Climate Change Task Group has now been reconvened to consider the industry’s approach to the next round of reporting. One of the new initiatives is to re-examine the evidence for climate impacts on wind strength.
National Grid has been supporting the RESNET project with Newcastle University and DNOs have joined this work. One of the project work packages is intended to provide a geographical weather generator for temperature and rainfall and a new wind model consistent with the latest climate change projections (UKCP09). DNOs are particularly interested in the work on the wind model and Newcastle University is currently working on this.
The Committee on Climate Change, Adaptation Sub-Committee (ASC) recently produced a Progress Report—“Managing climate risks to well-being and the economy”. This report assesses the current state of resilience to weather and climate of infrastructure, businesses, health care system and emergency services. The ASC praised the preparations of the networks industry for its activity in climate change adaptation and its preparedness to address key challenges.
The ASC reported that they found evidence that the electricity transmission and distribution sector are assessing climate risks, taking action in response, and reporting on progress against plans. They reported less evidence available within most other sectors.
The ASC noted that the electricity transmission and distribution sector has developed technical standards for managing current and future risks from flooding and storms. These provide a consistent approach across the industry to identifying the most critical assets at the highest level of risk in order to prioritise action. Application of these standards is used to make a business case to the regulator for funding resilience measures that provide value for money to the consumer through the price control process. The process includes an assessment of the risks from climate change.
Electricity Network Operators have a legal duty to undertake tree cutting, now called "vegetation management", in proximity of overhead power lines for reasons of safety, for example in order to safeguard children climbing trees. This has been a feature of both past and current legislation.
These safety clearances also provide clearance between trees and the adjacent overhead lines and thus inherently provide a level of resilience against tree induced faults during adverse weather conditions. That degree of resilience depends upon a range of factors including wind speed, the type of tree and the health of the tree.
Following studies into a number of extreme weather events in the 1990s and early 2000s, Government consulted on new requirements for improving overhead line resilience under abnormal weather conditions. This led to an amendment to the Electricity Safety, Quality and Continuity Regulations (ESQCRs) which required Network Operators to undertake a risk assessed programme of "resilience vegetation management", coming into force from 2009. The Guidance to the Statutory Instrument pointed to the use of the ENA document, ETR132 ‘Improving Network Performance under Abnormal Weather Conditions by Use of a Risk-Based Approach to Vegetation Management Near Electric Overhead Lines’ (March 2006).
Accordingly, Network Operators have to meet costs of vegetation management for both safety clearances and resilience clearances. These costs are considered by Ofgem as part of Price Control Reviews. As with flooding, the respective allowances are published and expenditure monitored on an annual basis.
This is a well established voluntary arrangement involving the Electricity Network Operators of the United Kingdom and Ireland, and is designed to provide mutual aid and assistance to member companies in the event of severe network damage, normally as a result of the weather. The agreement allows field staff and equipment to be deployed quickly to the areas of greatest damage in order that customers’ supplies can be restored as quickly as possible.
ENA provides the secretariat for the agreement and ensures that meetings of the members take place at least twice a year. One meeting is held in the autumn to prepare for the winter ahead and a further meeting is held in the spring to review any events over the winter. Other ad hoc meetings may be called at the request of members or ENA.
In deploying staff across the country where they are likely to be working in unfamiliar surroundings and potentially dangerous conditions there are a number of safety risks and the agreement sets out procedures to ensure safe working practices.
A key issue for DNOs is their preparedness to respond to the risks posed to their electricity networks by adverse weather. NEWSAC provides a forum for companies to share information on their planning for forecast events and then to share information.
NEWSAC was successfully invoked during a number of the storms last winter, however, due to the widespread nature of the Christmas storm and the threatening forecasts across the whole country, the opportunity for staff transfers at that time was more limited.
ENA and the E3C Electricity Task Group ETG led on a number of initiatives including a review and update to the NEWSAC agreement. Also as a result of the DECC review, Good Practice Guides have been produced in conjunction with the Electricity Task Group for the following emergency management activities:-
In addition, a review of documents relating to performance during severe weather will be undertaken during 2014/15 to take account of any learning points from the storms.Also, a considerable amount of work has been carried out to improve communication of key information to the public.
One aspect identified during the recent storms was the need to make it much easier for customers to contact their local network operator in the event of a power cut and this has resulted in the substantial project to introduce a Single Emergency Number. Work is progressing to deliver this and the current timeline is for a completion date of April 2016
To support the work of E3C and the Electricity Task Group, ENA and its members companies operate a regular Emergency Planning Managers’ Forum to share best practice in emergency planning and response. This group also oversees transferring ETG initiatives into detailed actions, particularly if it necessary to establish a Task Group of member companies to develop an enduring ENA engineering document.
This Group also carries out the detailed work on the public information systems that would be available in the event of a major power emergency including Rota Load Disconnection (RLD).
Increasing use of communications technology and data in the development of a smart grid will be vital to managing shifting patterns of supply and demand in the future energy system. However, it will create new vulnerabilities, with thousands of potential access points providing opportunities for cyber criminals.
Through ENA the industry is working together and with Government to increase understanding and awareness around cyber security.
ENA Energy Network Cyber Security Forum (ENCSF) has been established in order to:
The Forum provides an opportunity for debate and development of strategic direction and will initiate work to assess the implications for ENA Members of cyber security threats or issues. Through this forum, ENA position is developed and communicated to DECC, Ofgem and other key policy makers in order both to influence the national debate and to highlight the strategic importance of the energy networks.
Greater take-up of low carbon technologies like electric vehicles will see the increased electrification of our society and a doubling of the load on our electricity network.
The Low Carbon Technologies Working Group has been established to represent network operators interest in several areas.
The LCT assists with the development of UK Standards for Electric Vehicles (EV); Charging connections, charging infrastructure. This includes the development of the IET Code of Practice for the installation of charging infrastructure. At the European level the group maintains representation on Eurelectric’s task force for Electric Vehicles and keeps a watching brief on the potential of Vehicle to Grid (V2G) energy storage.
The LCT maintains links with BEAMA, OLEV, Ofgem and MCS, to assist these organisations with developing appropriate strategy and procedures for the installation of various LCTs. These include the recent OLEV grant for domestic EV charging point installation, notification process for small scale embedded generation (SSEG) and also the Renewable Heat Incentive (RHI).
26 September 2014