Electricity

Future-proof grids

Energy supply and demand have become far less predictable. The growth of decentralised, sustainable power generation facilities, such as solar farms, in particular, is very fast – so fast, in fact, that there is a risk of problems with our transmission capacity and voltage quality. A lot of solar roofs and wind farms have been constructed in Schouwen-Duiveland and Tholen in Zeeland, for example. These produce more electricity than is taken up in the area. We are looking for efficient solutions to maintain the vitality of our network.

Master Plan 2050

To understand how demand for energy will develop, we need to have a clear picture of the necessary energy infrastructure in the short, medium and long term.

The Master plan 2050 provides a framework for the development of overarching plans that give us insight into the required investments in Stedin's transmission and distribution networks in the longer term. In this way, we aim to prevent divestment and be ready for the transition. The spatial integration of the infrastructure is key to success. In the city of Utrecht alone, 65,000 m² of space below ground will be required until 2050. By making this transparent, we can reach agreements at the municipal and provincial level about space. This transparency contributes to social consensus, faster implementation and lower societal costs and investments. The master plans for the Rotterdam Port Area, Amersfoort, The Hague, Zoetermeer and Utrecht/Nieuwegein have already been delivered. We are still working on the other areas.

In 2018, the Netherlands Authority for Consumers and Markets (ACM) tightened the safety rules for newly constructed low-voltage grids. The ACM intends to make these safety rules applicable to the existing grids as well. This means that they will need to be monitored. Grids that do not comply with the safety rules will require modification. One solution is to disable the connections between two low-voltage grids. This has a positive effect on the energy flowing through the grids and short circuit currents. As a result, disconnected low-voltage grids comply more easily with the safely rules than when they are connected. An added advantage is that the disconnected low-voltage grids are also more easily adapted for the energy transition.

Shortage of transmission capacity

To make optimum use of the grid, we need to align plans as closely as possible with the available capacity and make maximum use of our current energy infrastructure. Grid managers work together on solutions with this aim. You can read more about this in the factsheet produced by Netbeheer Nederland 'Samen vernieuwen' (renewing together). Below, we detail a selection of our projects.

Dispensing with the failure reserve

The failure reserve is also referred to as the 'rush-hour lane' or N-1 or N-2 redundancy. Thanks to the failure reserve, the grid has a supply security of 99.99%. The failure reserve enables us to avoid or limit the duration of a service interruption in large areas due to a failure. It also allows us to carry out maintenance on our grids without having to interrupt supply to customers. The growth in sustainable energy generation makes grid reinforcement necessary, but this takes considerable time. For our 150 kV main distribution stations, legislation and regulations currently do not allow us to use the failure reserve to accelerate the connection of sustainably generated energy.

Many solar and wind projects do not require connection to the maximum capacity. By using the existing failure reserve in the grid, however, we would be able to connect them. In case of a failure or during maintenance work, the output of the solar or wind-energy installation is temporarily curtailed or disconnected without compromising the security of supply to other grid users.

Dispensing with the failure reserve involves more than a mere technical adjustment. We need the cooperation of the customers in the area who return energy to the grid. There needs to be an understanding of what N-1 means as well as what rights and obligations exist, and the grid manager and customers feeding power into the grid need to increase their cooperation.

Cable pooling

Cable pooling, which is permitted by law from July 2020, enables a cable to accommodate power generated from both and wind and solar on a single connection. This is important, in view of the limited utilisation of the total capacity of a connection in the case of generation plants for solar (12%) and wind (28%). After all, the wind does not always blow and the sun does not shine constantly. The connection must nevertheless be able to cope with periods of peak load. Cable pooling enables us to curtail the output of the solar or wind farm at peak times, when the capacity of the connection is not sufficient. This limits the amount of energy that is lost. As a result, we can increase the capacity utilisation of a connection to 39%, fewer connections are needed and we can absorb more generating capacity on the grid. In 2020, we set out these possibilities in further detail at Stedin, and we are working to ensure they are implemented. An initial application is currently under consideration from the owner of a wind farm who wants to expand the existing connection with a solar farm and then market the two separately.

Station of the future

The energy transition is causing us to expand substantially more stations as well as build new ones. It is imperative that we design and build these stations smarter. Fortunately, this is possible. How? By further standardising stations. While this is not always possible for entire stations, it is possible for the modules we use to put them together. Smart stacking of the modules, just like Lego, ensures that we retain enough flexibility to integrate the stations into the surroundings. In 2020, we created an environment for managing these standards, an improvement process was put in place and the modules were made available for the most common station type. In the coming year, we will develop the modules for the remaining types of stations. There are plans to build five such modular stations in Zoetermeer.

Flexibility

Congestion in our grids is becoming more frequent as a result of the energy transition. This is creating an increasing need for flexibility, either as a temporary measure until a grid reinforcement has been carried out or as a definitive measure. Flexibility offers new business and other opportunities for new and existing customers and a solution for making better use of the existing electricity grid and ensuring it remains affordable. The System Operator strategic initiative provides a framework for deploying flexibility.

Using the present and future electricity grid as efficiently as possible is crucial to flexible operations. We do this, among other things, by involving and deploying end consumers, municipalities and housing associations in a flexible energy system. This gives us a firmer grip on the number of peaks resulting from the energy transition, with the objective of reducing 30-40% of these peaks. In 2020, flexible capacity on demand was utilised 16 times in the Zuidplaspolder pilot and GOPACS, for 20 Megawatt in total.

Examples of flexibility projects are GOPACS, Zuidplaspolder and the test beds in Hoog Dalem and Bleiswijk.

Grid operators platform GOPACS successfully launched

GOPACS is a joint initiative of the regional and national grid managers that is intended to solve congestion issues, local and otherwise. The solution is based on local flexibility markets, with participating parties indicating at what price they are willing to consume more or less electricity or return it to the electricity grid. As soon as there is a risk of congestion on the grid, the grid manager appeals for flexibility. Flexibility crucially depends on the presence of enough participants with flexible demand for or production of electricity. In 2020, the first group of 27 customers were registered on the grid operators platform GOPACS. In this way, they, together with other participants, are increasing the availability of flexibility in the market.

In cooperation with an aggregator, we simulated a congestion situation in the Bleiswijk grid area in which we actually called up flexibility via GOPACS for an area in Zoetermeer. This fundamentally demonstrated our capability to utilise flexibility from the market with the GOPACS platform.

Expansion of electricity grid in Zuidplaspolder

Demand for electricity in Zuidplaspolder has increased significantly in recent years. To ensure that we can continue to supply new businesses and new housing developments in this area with electricity in the future, we are expanding the capacity of the grid. To facilitate this, grid managers TenneT, Stedin and Liander are building a new high-voltage station alongside the A12 motorway – N219 expressway near Zevenhuizen in the municipality of Zuidplas. The construc­tion of the new Zuidplaspolder high-voltage station is a major undertaking, the preparations for which began two years ago. The zoning plans need to be amended to permit the construction and installation of the cable connections. This requires the involvement of the municipalities of Zuidplas, Waddinxveen and Lansingerland. Once this process is completed, the preparatory work can commence in mid-2022.

LEF: Local, Energy and Flexible

The LEF concept involves a local energy system in which local residents and businesses smartly combine their own power generation and consumption. This drives down costs for themselves as well as the entire system. Test beds have been set up in Hoog Dalem (Gorinchem) and Greenparc (Bleiswijk). In 2020, the participants in the residential district of Hoog Dalem were challenged to actively reduce the peaks in the grid, for example by making smart use of their heat pumps or induction cooktops at times forecast in advance. At the end of 2020, three 12 kW batteries were installed at the participants in preparation for the launch of automated energy trading in early 2021. As much locally generated green energy as possible now remains in the district, and the peaks in our grid are reduced as a result.

Stedin is a member of Energy Web, which has established a blockchain specifically for the energy sector. We are applying this technology in the test bed being conducted in Hoog Dalem.

Stedin is working with the businesses participating in the Greenparc Bleiswijk pilot and Eindhoven University of Technology to develop a future-proof rates system for heavy-use connections. This system provides for more efficient use of available capacity in the local grid. We are also researching whether sustainable investments by customers in smart charging squares or battery storage, for example, can be better rewarded by applying this conceptual rates system. This pilot will go live in the second quarter of 2021.

Stedin is also providing support and know-how for customers' initiatives resulting in the creation of 'local energy communities', including the 'Groene Mient' (The Hague) and 'Eemnes Energie' projects.

Reinforcement

Reinforcement of the electricity grid entails lengthy lead times. As it takes roughly two years to replace a medium-voltage station, new solar farms often face a long wait before they can be connected.

Grid capacity problems on Schouwen-Duiveland and Tholen electricity grid

Grid manager Enduris expects that the limit for returning energy by large, new solar roofs and wind farms to the grid of Schouwen-Duiveland and Tholen will be reached in the foreseeable future. The solution for Schouwen-Duiveland and Tholen is to create an additional connection to TenneT's national high-voltage grid. This is a time-consuming undertaking, which takes roughly 7 to 10 years to complete on average. TenneT and Enduris have already spent two and a half years making the necessary preparations. The public consultation to determine the location for the station will begin in the first quarter of 2021. The station will not be completed until the end of 2025 at the earliest.

Notification of structural congestion

As temporary solutions will not remedy the problem, Enduris has formally given advance notification of 'structural congestion'. This means that Enduris will be unable to provide any capacity guarantee for large, new solar and wind farms on Tholen and Schouwen-Duiveland until the new connection is provided. This has no implications for consumers' new and existing solar panels, as there is still sufficient capacity for them on the electricity grid.

The RES for Zeeland sets out that the electricity grid on Schouwen-Duiveland and Tholen will soon reach its maximum capacity. There are therefore no consequences for the RES for Zeeland for the time being.

Generation

Regional Energy Strategies

The commitments in the Climate Agreement relating to electricity and the built environment require each region to develop a Regional Energy Strategy, or RES. In 2020, the 14 RES regions in which Stedin and Enduris are involved developed these plans further in collaboration with the provincial and municipal authorities and water authorities, among others. The regions face the complex challenge of making suitable choices in terms of ambition, support, space utilisation and infrastructure, among other things.

Services provided to RES regions

Stedin actively participates in working groups in RES regions, contributing knowledge of the structure of the grid and the most suitable places in the present grid for facilitating additional energy generation from renewable sources. Together with the regions, the ambition is further specified, backed up by grid impact assessments that have been carried out for all the regions. In this context, we determine the impact of the proposed scenario in terms of the required space, the time needed to carry out the grid expansions and the necessary investments in that regard.

Draft RES

By 1 October 2020, each RES region had submitted its draft RES. The total ambitions far exceeded the national target of 35 TWh large-scale onshore renewable energy generation capacities, with a total nationwide in excess of 50 TWh. It is good to see that there is so much drive to meet the climate targets. Many regions also focus heavily on using roof areas for the installation of solar panels.

Toward the RES 1.0 and beyond

The RES 1.0 should be ready by July 2021. The plans are being tightened up and made concrete at the regional level, in preparation for their submission to municipal councils. The next step is to draw up implementation plans and provide them with a solid legal basis in accordance with the Environmental and Planning Act (Omgevingswet). It is envisaged that these steps will enable permits to be issued in 2025.

Potential for tension

The impact analyses that were carried out show that major grid expansions are needed to facilitate the regions' plans. Expanding and reinforcing our electricity grids can take several years. This is due to studies that need to be carried out into the available space and purchasing and permit procedures, for example, as well as work that needs to be undertaken to involve local stakeholders in the process. The understandable desire among municipalities and regions is for investments in the grids to be made early in the planning phase so that, once the plans have been finalised, work can immediately forge ahead. Investing too early carries risks for Stedin. Plans can still change at a later phase. For example, planned wind turbines may be rejected after a participation process. Or a different energy solution or other area may be chosen. In that case, it is possible that the investment was not necessary or was not appropriate in that particular area. In addition, this may mean that a different investment, which does prove to be necessary, cannot be made as a result, or cannot be made in a timely manner. If network calculations show that our grid needs expanding, we try to get a concrete and certain picture. Once we have such a picture, we include the plans of a municipality or province in our investment portfolio.

Staying on course together

Linking municipalities' portfolio of projects to Stedin's investment calendar enables us to make the right invest­ments in a timely manner. It also allows us to make the energy transition predictable and something we can plan for. It is important, therefore, that we stay on the agreed course together, even if that course offers more room for manoeuvre in the long term than in the short term.

Making network information available

Digitalisation and data management

To advance the energy transition in an affordable manner, Stedin needs to have digital insight into everything that happens in its grid. With this insight, it can make optimal use of the present grid and make data-driven investments to facilitate future developments. This requires our IT and OT infrastructure (OT infrastructure comprises the smart sensors in our network that detect whether the voltage is correct and reliable, for example) to be flexible, affordable and safe. In addition, all the information needs to be gathered and accessed in a way that enables the correct decisions to be made.

In 2020, the second version of the Stedin data lake was taken into use. Data lake 2.0 is a work environment for the data science team, as well as the new 'business intelligence' environment for all of Stedin, in which reports and dashboards are available. This lays the foundation for increasing amounts of data to be made easily available to staff. The migration to a cloud environment has been completed, ensuring that we can work more safely, efficiently and effectively. We have also finished implementing our data warehouse, in which data are placed in context and made readable so that they can be used by data analysts and data engineers.

Data science

The data science team completed several successful cases again in 2020. For example, the team demonstrated that we can detect the presence of hemp farms in the data from more than 2,000 smart grid terminals that have been installed in the grid. Work was also undertaken to develop models to provide short-term load projections for the electricity grid. These models are important for experimenting with the flexible consumption, generation or feeding in of electricity.

Models were also produced with which operational processes can be more efficiently supported. Processes that benefit from this include the assessment of photographs during the customer request intake phase, for example, as well as the planning of service engineer work schedules and efficiently creating a detailed design of an electricity grid for a district. These models will be taken into use in 2021.

Data governance

Data owners and stewards have been appointed across all of Stedin. The domains for which they are responsible have been defined and published. Data can now be more easily found within Stedin, which is a precondition for extracting more value from them. In cooperation with several departments, structured data quality measurements were set up to improve data reliability.

Next-generation assets

Next-generation smart sensors are being introduced in the grids to ensure continual and up-to-date insight into grid loads and the freely available capacity. Smart sensors enable us to carry out remote grid measurements and, depending on the specific sensor, perform remote switching or enable autonomous switching.

Medium-voltage stations

We are making medium-voltage stations smarter by installing Smart Grid Terminals (SGTs). The SGTs generate data, which we safely make accessible to make them available for use. Among other things, we collect data on the power that is being transmitted. The SGTs also assume the switching function for public lighting.

Distribution automation

Up-to-date insight into the quality and capacity of the distribution network is a key enabling criterion for our role as a system operator. In this light, policy for distribution automation (DA) was developed in 2020 in which this is elaborated. In mid-2021, we will switch to using a new smart sensor, the DA box. The installation rate of these types of smart assets will increase in the coming years. At the same time, work will be undertaken on implementing a read-out chain. This chain is a further development of the smart meter chain, in which optimum use is made of the lessons learnt from the smart meter chain. The data from smart sensors and meters provides us with up-to-date insight into the status of the grids and enables us to calculate the effects of future scenarios. This enables more efficient and effective management of our grids.

Low-voltage grid

Energy generation from renewable sources is accompanied by high variability in generation and consumption. This underlines the importance of also making the low-voltage grid (LV grid) smarter, to provide us with data on and insight into the situation at a part of the LV grid. DA light enables us to undertake rapid modification of our LV grid. Actual implementation will begin in 2021.

New algorithm for retaining voltage quality

In addition to a strong increase in energy feed-in, the energy transition is also giving rise to a significant increase in the fluctuation of supply and demand in the low-voltage network. As a result, the classic algorithm used by grid managers, which assumes predictable consumption and zero generation, is no longer adequate. Without additional up-to-date insight into the LV grid, this development will lead to decreased voltage quality and hence increased customer complaints. In case of disruption to energy feed-in, it may even lead to financial loss for customers. The insight provided by smart meters enables the grid manager to implement appropriate measures in a planned, timely and efficient manner. Without this insight, we can merely react in case of incidents and complaints, and we are then forced to resolve the issues, which may already be urgent, with sub-optimal measures at unnecessarily high cost. In 2020, several cases were developed and implemented that increase this insight into our current grid situation and also improve the ability to rapidly resolve and effectively remedy low voltage failures. As a result, we were able, among other things, to implement measures to prevent failures affecting customers and disconnect the output of solar panels before the problems could arise and affect the customer.

Telecom

Since October 2018, Stedin has been phasing in the use of a new fibre-optic network (Stedin Telecom Network) across Stedin's entire area. This modern telecommunications network establishes a data link between all the automation systems in transmission stations and the larger medium-voltage distribution stations in Stedin's area. This will improve our insight into the functioning of the energy grid. This network has now been implemented in The Hague and parts of Rotterdam, Dordrecht and Utrecht. The aim is to have completed full service implementation across Stedin's entire area by 2022.

Using available network information for the energy transition

The energy transition requires us to be able to conduct rapid assessment of our grids. This is referred to as 'quantifying grids'. The next step is a digital model of the grid that includes switching statuses and measurement data. This provides greater insight into business operations and grid planning. We also need to assess future grid designs in the context of the Regional Energy Strategies (RES). We use the solution for quantifying grids for this purpose. The insights gained into the challenges posed by the RES enable us to implement timely and targeted reinforcement measures.

Availability of smart meter data (in per cent)

Ensuring the safe, reliable and efficient availability of smart meter data is becoming increasingly important for facilitating market processes. Market parties seek optimum insight into their customers' consumption patterns and volumes so they can optimally predict their energy requirements and are expected to increasingly offer flexible tariffs to their customers. This will result in an increased number of smart meter read-outs. Legislation on a 24-month data storage requirement is also leading to a substantial increase in the number of smart meter read-outs. Guaranteeing the short and longer-term availability of connectivity for accessing and reading out smart meters is an important precondition. For this reason, Stedin uses the CDMA telecommunications network. In 2020, investments were made that make it possible to extend the service life of the CDMA telecommunications network until 2034. In 2021, we will install LTE meters at the locations that lack CDMA telecommunications network coverage. The negotiations with telecom providers on using the GPRS network are continuing, in cooperation with other grid managers.