Electricity security of supply Executive summary

Transcription

1 Electricity security of supply 2016 Executive summary

2 Preface Danish security of electricity supply remains at a high level. However, although 2015 was yet another year with very few power outages, our analyses show that initiatives must be launched to maintain the high level of security of electricity supply in future. In 2014, Energinet.dk decided to make a call for tenders for extra capacity on Zealand. However, the call for tenders had to be cancelled in December 2015, as the European Commission found it to be in violation of the rules on state aid. Following, Energinet.dk is working on new solutions to maintain a high level of security of electricity supply also in Eastern Denmark. and establishment of a joint office in Copenhagen focusing on operational coordination. The following pages are a summary of Energinet.dk s 2016 report on security of electricity supply. Here you can read about the outage statistics for 2015 and some of the solutions we are implementing to maintain a high security of supply. Finally, you will gain easy insight into how security of supply cuts across the entire value chain from producer to consumer and across national borders. Enjoy! In 2015, important steps were taken in the international cooperation on security of electricity supply. A large number of network codes are in the pipeline, and will have a significant impact on the legislative framework for security of supply. At Nordic level, cooperation has been strengthened with a Nordic cooperation strategy 2

3 Content Security of supply is vital to society...4 Energinet.dk s security of supply tasks... 5 Security of electricity supply Security of supply across borders...8 Generation adequacy on Zealand Balance in the physical electricity system Maintenance of the electricity system

4 Security of supply is vital to society The Danish security of electricity supply ranks among the best in Europe, and Danish consumers have benefitted from a very high level of security of electricity supply for many years which is necessary, as secure electricity supply is essential to basic functions in society, including hospitals, businesses, and private consumers. A high level of security of supply is the result of complex interaction between the physical electricity system, the electricity market, producers and consumers. Ensuring a high level of security of supply is thus not only a matter of quantity and size of power stations, wind turbines and power lines. Security of electricity supply is measured by whether there is power when the consumer turns on the switch. Security of supply monitoring is carried out through regular risk assessments, estimating the probability that electricity is available to consumers on demand according to generally accepted methods. system adequacy is the power system capable of covering demand? system security is the power system capable of managing errors? elecitricity security of supply System security is the electricity system s ability to handle sudden failures. System adequacy is the electricity system s ability to handle the production capacity required to meet the demand. In practice, the above grid properties overlap. 4

5 Energinet.dk s security of supply tasks Energinet.dk has the overall responsibility for security of electricity supply in Denmark. It involves the following tasks: Monitoring security of supply in the electricity system from producer to consumer. Ensuring physical balance and technical quality in the overall electricity system. Operation, maintenance, and expansion of the transmission grid to maintain a high level of security of supply. Ensuring production capacity in cases where market mechanisms are insufficient. Development of a framework for an electricity market capable of balancing consumption and production. Energinet.dk s objective is for security of supply in the Danish electricity system to remain among the highest in Europe. To achieve a high security of supply, the planning and operation of the electricity system must be carried out in cooperation with electricity system players, including foreign partners. The task of ensuring balance in the electricity system with large volumes of renewable energy is more complex to-day than in 1996, when I started. It s an exciting challenge requiring that we make an effort. Lars Fogt Andersen, Senior Operator in Energinet.dk s control centre 5

6 Security of electricity supply 2015 Outage statistics Again in 2015, the level of security of electricity supply was high with only a few minutes of outage per consumer. Outage minutes per consumer per year (consumption weighted) There have been no long-term power cuts in Denmark in the past 10 years. Cable laying of the distribution grid has significantly contributed to the reduction of the number of power cuts for consumers. The storms in 2013 were comparable to the storms in 1999 and 2005, respectively, but did not cause any significant power cuts. This was also the case with the storm Gorm in November Incidents In 2015, Energinet.dk did not disconnect consumers to maintain stability in the overall electricity system (brownout), and there were no cases of a complete breakdown of the electricity system (blackout). Error (1-24 kv) Planned (1-24 kv) Interruptions on kv Force majeure (1-24 kv) 5-year average 10-year average Outage statistics for Denmark from 1999 to

7 I m proud that again in 2015, Denmark was able to ensure a very high level of security of supply at the same time having a wind power share of 42%. Søren Dupont Kristensen, Vice President, System Development and Electricity Market Incidents affecting operations are reported to the Incident Classification Scale (ICS) joint statistics for transmission system operators (TSOs). In 2015, the number of incidents resulting in a violation of the voltage standards dropped from just over 40 to zero. One of the reasons for this is that Energinet.dk in 2015 established a new TSO operation function focusing on voltage control. Furthermore, various market conditions and the commissioning of Skagerrak 4 interconnector have contributed to the reduction. In 2015, seven incidents involving loss of IT tools which affected the control centre were registered of which one has affected neighbouring areas and was thus reported to the ICS statistics. In 2015, there were no situations with unstable operation and concurrent local and regional disconnections, which is why no emergency states were reported. In 2015, Energinet.dk reported alert state in connection with: The solar eclipse in March 2015 The storm Gorm in November 2015 Criteria Scale 0 Scale 1 Scale 2 Scale 3 Faults on elements in the transmission sytem (HVDC) Exceeding voltage levels Loss of IT tools 2013: : : : : : : : : : : : 1 List of incidents reported to the ICS statistics for Denmark in Loss of IT tools can only be reported as scale 1 or 2. 7

8 Security of supply across borders Changes to the electricity systems in our neighbouring countries are of key importance to the Danish electricity system, electricity market, and security of electricity supply. Close European cooperation and resource sharing are essential for cost-effective security of supply and green transition of the electricity system. Going forward, Energinet.dk s handling of security of electricity supply will include more on tools that are founded in European regulations. Thus, this will contribute to the development of more uniform tools for ensuring security of supply across Europe. And following, discussions on which tools TSOs can apply will to a larger extent take place at European level. for consumers to decide individually on the level of security of supply for which they are willing to pay. Operational cooperation strengthened on daily basis Cooperation calls for harmonisation of rules for connecting and operating plants across national borders. Therefore, common European regulations (network codes and guidelines) are currently drawn up. They will provide a framework for increased cooperation between operators of transmission systems. A common market contributes to security of supply The ambition of the European energy policy is for the electricity market to play a pivotal role in maintaining a high level of security of supply. The long-term vision is 8

9 Solar eclipse in Europe cooperation and renewable energy In March 2015, the power generated by the many European solar cells suddenly disappeared from the grid, but reappeared after a while. The reason for this was the solar eclipse. Every minute, large volumes of power corresponding to the output generated by a large Danish power station disappeared from the grid as the moon passed in front of the sun, and reappeared with even greater strength when the moon moved away from the sun. Such extreme situations pose a major challenge for the grid. Before, during and after the eclipse, European TSOs engaged in close cooperation with a view to addressing the situation, and the results were positive. The solar eclipse successfully demonstrated that European cooperation facilitates the inclusion of large volumes of fluctuating, renewable energy and control of the grid even in extreme situations. 9

10 Cross-border cooperation requires patience and compromises. We have different cultures and approaches, which makes openness to different solutions vital. International solutions offer great potential and are the way forward. Carsten Jensen, Vice President, Electricity Operation Initiatives for cooperation and common rules in Europe As part of the establishment of the Energy Union, the European Commission will implement two significant legislative initiatives already in 2016: a proposal for new regulation of the electricity market, and a new and more cohesive regulation of security of electricity supply. Pan-European network codes and guidelines Energinet.dk continues to participate in the development of network codes and guidelines, and to engage in other European cooperation forums in the energy area. Nordic office for regional cooperation in 2017 The establishment of the Nordic office for regional cooperation in Copenhagen significantly strengthens Nordic coordination. The office is to perform coordination tasks in relation to capacity calculations, outage planning and system reliability analyses. The office is expected to open in late Joint assessments of generation adequacy in 2017 In line with the development plan for new joint assessments of generation adequacy in ENTSO-E, the first analysis results will be available by mid Furthermore, the four Nordic TSOs have decided to carry out joint assessments of generation adequacy in the course of 2016 and

11 Generation adequacy on Zealand The risk of disconnection of consumers in the period is higher for Eastern Denmark than for Western Denmark. This is, among other things, attributable to Energinet.dk not being able to purchase the strategic reserve, which was expected to be introduced from the beginning of Energinet.dk had to cancel the call for tenders as the European Commission found the reserve to be in violation of the EU rules on state aid. Energinet.dk estimates that the risk of insufficient power in Eastern Denmark in the coming years will exceed Energinet.dk s objective of a maximum of five minutes of insufficient electricity supply * per consumer. Energinet.dk expects to meet the objective again in 2020, when the Kriegers Flak interconnection is planned to be commissioned. A possible delay of Kriegers Flak will increase the risk. After 2020, the objective will be challenged again. * 1 output minute corresponds to the average electricity consumption per minute. For Zealand, this is around 26 MWh/min. Reinvestments in grids and power stations increase the challenge In the coming years, several grid and transmission systems will undergo replacement or maintenance. This means more and longer outage times than previously, which again increases the risk of consumers being disconnected. Projects affecting security of supply include: Replacement of the Øresund cables. Connection of a biomass-fired unit at Amager Power Station. Reinvestment at Avedøre Power Station. Based on the historical extent of maintenance, the risk assessment for Zealand is seven outage minutes in However, as the extent of maintenance will increase significantly over the coming years, as previously mentioned, these assessments are not fully comprehensive. Instead, if the assessments are based on expectations of 11

12 outage time as set out in the long-term outage plannig, it will increase to 30 minutes. The difference between 7 and 30 minutes corresponds to an expectation that the consumer risks having % of the demanded energy supplied compared to %. A more representative picture of the need for maintenance will be available when the one-year outage planning has been prepared. Investigations have already been initiated of risk-reducing initiatives during high-pressure periods to ensure that the right tools are in place. Outage minutes per consumer per year (consumption weighted) With historical outages statistics With known revisions and strategic reserve With known revisions Estimated output minutes on Zealand in 2018 with various assumptions concerning maintenance. 12

13 Initiatives for improvement of generation adequacy Maintenance planning short term Planning of maintenance work is an important mean to improve the challenged adequacy situation on Zealand in the coming years. Energinet.dk is therefore working to improve the detailed maintenance planning including transfer of transmission system and production facility maintenance. Planning the summer period tends to be particularly comprehensive, which is the preferred time of the year for maintenance work. Strategic reserve short term Energinet.dk still estimates that a strategic reserve is an appropriate tool to enhance generation adequacy on Zealand in the coming years. Energinet.dk is therefore striving to realise this solution in the period New electricity interconnections long term Energinet.dk is currently evaluating the output and costs of electricity interconnection between Eastern and Western Denmark, and has furthermore entered into cooperation with the Polish TSO to investigate the possibilities of an electricity interconnection between Zealand and Poland. New interconnections, however, can only contribute to improving generation adequacy in the long term. 13

14 Balance in the physical electricity system Procurement of ancillary services (reserves and properties required to maintain power system stability) makes it possible to handle failures and ensure balance in the physical electricity system. Reserves are production capacity, which can be activated should the need arise. Properties required to maintain power system stability are the services required to maintain the safe and stable operation of the electricity grid, ie frequency stability, voltage stability and short-circuit power. The need for properties required to maintain power system stability can be covered by power stations, synchronous condensers, and power-electronic grid components connected to the transmission grid. In 2015, ancillary service costs declined. This is, among other things, attributable to the drop in the cost of automatic reserves in Eastern Denmark and the procurement from market players of properties required to maintain power system stability. The reason for the drop is the commissioning of Skagerrak4 interconnection and the synchronous condensers in Fraugde and Herslev. Future need for properties required to maintain power system stability In autumn 2015 and spring 2016, Energinet.dk conducted extensive analyses of the future need for properties required to maintain power system stability in Western Denmark, and presented the results to the suppliers of such properties. The analyses of Western Denmark show that the need for properties required to maintain power system stability, in addition to the system s own contribution, can practically be confined to a need for voltage control. The conclusion for Western Denmark is that during normal operation, there is a need for procurement of one ready-state unit in the summer period, provided that other grid components are in service. The need is not expected to change significantly up to and including

15 Initiatives to create balance in the physical electricity system New analysis of required needs for Eastern Denmark in 2017 In 2016, a new analysis of the need for properties required to maintain power system stability for Eastern Denmark has been initiated. The work is expected to be completed in spring Ancillary services providers HVDC-VSC units Central power station Synchronous condensers Activation of grid components Several players have pointed to the need to examine how Energinet.dk activates its own grid components in relation to the market players systems. This work has been initiated following the Market Model 2.0 project conducted in autumn Assessment of system security risk Going forward, the risk assessment method developed to assess system security risks will be applied extensively. The first specific project for which the method will be applied are analyses of a new interconnection between Eastern and Western Denmark. The location of existing units with properties required to maintain power system stability for Eastern and Western Denmark. 15

16 Maintenance of the electricity system Adequate and secure electricity infrastructure involves not only timely planning of new grid components, but also timely and cost-effective maintenance of existing electricity infrastructure. The electricity grid was significantly expanded from the 1960s to 1990s. Primary transmission grid components have an expected service life of 40 years, which means that Energinet.dk will have to carry out extensive work to plan and prioritise reinvestments in the coming years. With an asset portfolio of approx. 250 substations, 4,800 km of overhead line and 2,100 km of submarine and land cable, average reinvestments include more than six substations per year and about 52 km of cable and 120 km of overhead line per year. 16

17 Initiatives to maintain the electricity system New reinvestment strategy Energinet.dk is currently preparing a new reinvestment strategy to help maintain a high level of security of supply. An extended analysis of the state of the electricity system will be introduced as a tool for managing the reinvestments, which is to form the basis for assessment of the need for an entire section or substation. In addition, the reinvestments will be subject to quarterly monitoring and reporting to ensure efficient coordination and reduction of grid outage times due to maintenance work. New load forecasting method Energinet.dk has developed a new load forecasting method taking into account that the electricity consumption in a geographical area depends on the demographic shift from peripheral areas to growth areas. In future, this method will be applied in the assessment of reinvestment needs. Assessments of reinvestments in Copenhagen will be the first project to apply the method. Improvement of faults and incidents statistics at EU level Energinet.dk continues to improve the Nordic and European cooperation on faults and incidents statistics to ensure that relevant knowledge can be included in the electricity system maintenance work. 17

18 Energinet.dk Tonne Kjærsvej Fredericia Tlf