Amprion: “Smart Valve” for flexible power flow control

05.08.2020

To maintain the stability of the transmission grid despite the current increase in decentralised and volatile generation, the German transmission system operator (TSO) Amprion – like many other TSCNET shareholders – is already using a wide range of innovative technologies, for instance Phase-shifting transformers (PSTs) or reactive power compensation systems such as Statcom. A promising pilot project has now additionally been launched, for which Amprion has signed a cooperation agreement with the US Silicon Valley company, Smart Wires. In the three-phase project, the mobile modular static-synchronous series compensator (mSSSC) developed by Smart Wires, the so called SmartValve, will be deployed in the Amprion grid.

The aim of the project is both to increase the transmission capacity of Amprion’s transmission grid and to maintain its high level of system stability. SmartValve is designed for a more balanced and thus more efficient use of power lines. By actively changing the power flows, it enables better control of the transmission system and minimises redispatch. Due to its modular structure, SmartValve is easy to transport and can be operated flexibly at different locations. This distinguishes the new technology from conventional PSTs, for example, making it an ideal complement to support the system from a stability perspective.

Dr. Klaus Kleinekorte, CTO at Amprion, refers in this context to the significantly increased costs for redispatch in Germany in recent years due to the changes in the energy landscape. This is where the SmartValve project comes in: “We see this innovative technology as having the potential to allow us to use the network more efficiently and reduce the need for redispatch.” The two partners expect the project to span two to three years to verify the added value of the new technology in the Amprion grid.

Amprion and Smart Wires launched a pilot project to implement the SmartValve solution in the transmission grid (picture: Smart Wires)

Linkup
> See Amprion press release (html)

See article on single page

Swissgrid analyses supply disruption in Valais

22.07.2020

On Friday, 17 July, the Swiss transmission system operator (TSO) Swissgrid carried out check-operations concerning the extension of the 220kV switchgear in the Chippis substation in the canton of Valais. At 4.23 p.m., the protection equipment of the 220kV grid node Creux de Chippis was accidentally tripped, causing the switchgear to lose voltage. As a result of the technical failure at Chippis, the switchgear of the substations in Stalden, Bitsch, and Mörel were also affected by the voltage drop, which led to a regional supply interruption in the distribution system.

The result was a one-hour power outage in a total of 60 municipalities with around 112,000 households as well as trade and industry in the Swiss Sierre district and the largest part of the Upper Valais. By 5.23 p.m., all affected switchgear and lines of the TSCNET shareholder were back in regular operation. Thanks to the good cooperation between Swissgrid and the five affected distribution system operators (DSOs) of the lower voltage levels, it was possible to gradually restore the electricity supply from 5 pm onwards. By 6.15p.m. almost all customers were back on power. Swissgrid immediately initiated a detailed investigation of the incident, which is currently in progress.

Swissgrid is investigating the voltage loss in the switchgear of the Chippis substation in Valais on 17 July (picture: Swissgrid)

Linkup
> See Swissgrid news release, in German (html)

See article on single page

Worldwide unique equipment for TransnetBW substation

18.07.2020

European transmission system operators (TSOs) respond to the increasing need for grid regulation – resulting from the growing share of volatile renewable energies and the proceeding shutdown of conventional power plants – with reactive power compensation measures, such as the installation of shunt reactors. Shunt reactors are absorbers of reactive power and support security of supply and system management by keeping the grid voltage within the specified range, especially during low load periods. They thus stabilise the power grids and increase the energy efficiency of the transmission system.

In the Stuttgart-Mühlhausen substation, TransnetBW, one of the four German TSOs, has commissioned a variable shunt reactor for reactive power compensation developed especially for the TSCNET shareholder. Up to now in the TransnetBW control area, shunt reactors have only been used in the 110kV grid. Compared to customary reactors, the new system provides a much more precise control of the grid voltage. The 360-tonne reactor has a control bandwidth of 50-250MVAr in 33 stages and a permanently permissible system voltage of 440kV. With these specifications, the Mühlhausen shunt reactor is not only a novelty for TransnetBW, but for the entire energy sector.

TransnetBW has commissioned a state-of-the-art shunt reactor in the Stuttgart-Mühlhausen substation (symbolic picture: Siemens)

Linkup
> See TransnetBW press information, in German (html)

See article on single page

Construction permit for Pradella-La Punt

13.07.2020

As the extra-high voltage line in the Swiss Engadine between Pradella and La Punt constitutes a bottleneck in the Swiss and pan-European transmission system, the Swiss transmission system operator (TSO) Swissgrid has long aimed to increase its transmission capacity to 2 x 380kV. This will improve import capacity and security of supply in the canton of Graubünden and facilitate the transport of Engadine hydropower. The project is part of the “Strategic Grid 2025”, Swissgrid’s ambitious modernisation and expansion plan.

The Swiss Federal Inspectorate for Heavy Current Installations (Eidgenössisches Starkstrominspektorat-ESTI) now has approved the reinforcement and new construction of pylons between Pradella and La Punt. Swissgrid has already refurbished the pylon foundations in the past two years, so that work can commence soon. Approximately 3500 tonnes of steel will be needed to upgrade the around 50-kilometre-long overhead line. The construction will be carried out in two sections and is expected to be completed by the end of 2022.

To reduce the overall environmental impact in the region, Swissgrid is supporting a local grid operator in replacing a 60kV overhead line with a 110kV underground cable. As a result, 1100 pylons will be disappearing from the landscape.

Swissgrid can start with the 2 x 380kV upgrade of the Pradella-La Punt line (picture: Swissgrid)

Linkup
> See Swissgrid media release (html)

See article on single page

Smart control of heat pumps – HeatFlex expands

08.07.2020

Launched in the summer of 2018, the HeatFlex research project aims to exploit the potential for grid stabilisation that small and decentralised consumer devices can offer – if actively involved in the stabilising process. The founding project members are TSCNET shareholder TenneT, the Dutch-German transmission system operator (TSO), and the southern German distribution system operator (DSO) Bayernwerk Netz. Following the successful cooperation and positive test results, TenneT and Bayernwerk Netz are now expanding the project. The grid operators are pleased to welcome three new project partners: the DSO Regensburg Netz as well as the public utilities Stadtwerk Haßfurt and SWW Wunsiedel.

With HeatFlex, TenneT and Bayernwerk are jointly researching the most effective integration of decentralised devices – such as electric storage heaters, heat pumps, and water heaters – into grid balancing. These flexible capacities are intended to avoid cost-intensive interventions by the TSO in the case of future grid bottlenecks. Since November 2019, the project partners have already been implementing the first concrete measures based on HeatFlex results: The heat pumps and direct heating systems connected to Bayernwerk Netz are being intelligently controlled for bottleneck prevention. Decentralised heating systems are thus partially taking over the stabilising function of fossil plants. Using ripple control technology already in place, no additional investments are required.

The increase in partners should serve to make intelligent use of even more local flexibility and to investigate further controllable, decentralised consumption units and alternative applications. The ultimate aims of HeatFlex are cost savings, reduction of grid extension, and the acceleration of the energy transition without jeopardising system security. “The intelligent control of the smallest, decentralised electricity consumption units is a small but essential element,” explains TenneT Managing Director Tim Meyerjürgens, “because the many pieces of the puzzle together make up the overall picture of the energy transition”.

The research project HeatFlex is extended with three additional partners (picture: Stiebel Eltron)

Linkup
> See TenneT press release, in German (html)

See article on single page

SVC for SINCRO.GRID in Konjsko

02.07.2020

As in many parts of Europe, the increasing integration of decentralised, volatile renewable energy sources has also led in Croatia and Slovenia to a lack of flexibility and reactive power. The two TSCNET shareholders HOPS, the transmission system operator (TSO) from Croatia, and ELES, the Slovenian TSO, react to this with their joint project SINCRO.GRID that also involves two distribution system operators (DSOs) from the respective countries. The European Project of Common Interest (PCI) aims to optimise the efficiency of the two national electricity transmission networks through advanced technologies and innovative data processing methods. These include compensation devices, a dynamic thermal rating system, a battery power storage system, and a virtual cross-border control centre.

The start of construction of a static VAR compensator (SVC) in the Dalmatian substation in Konjsko on 30 June represents another significant milestone in the implementation of SINCRO.GRID. This state-of-the-art compensation system will support HOPS in actively controlling the reactive power flows in the Croatian power grid. The ceremony to mark the construction start was attended by high-ranking representatives of the Croatian government and the energy companies involved.

In addition to the SVC in Konjsko, SINCRO.GRID comprises three further main elements in Croatia: a variable shunt reactor (VSR) in the Mraclin substation near Zagreb, which was commissioned in January 2020, another VSR in the Melina substation, which is scheduled to be commissioned at the end of 2020, and finally a joint Croatian-Slovenian virtual control centre. Tomislav Plavšić, President of the HOPS Management Board, describes the latter as a unique solution for coordinated voltage regulation on the entire territory of both countries. The principal task of the binational virtual centre is to integrate three devices each in Croatia and Slovenia for reactive power compensation into one common operation to fully exploit their synergy potential.

HOPS has commenced construction of a SVC as part of the SINCRO.GRID project in Konjsko (picture with Tomislav Plavšić in the foreground: HOPS)

Linkup
> See HOPS press release, in Croatian (html)
> Visit SINCRO.GRID website (html)

See article on single page

High-voltage pylon of Swissgrid sabotaged

28.06.2020

On the morning of Friday 26 June, motorists on the Lausanne-Geneva motorway near the municipality of Gland in the Swiss canton of Vaud noticed how a high-voltage pylon collapsed. The cantonal police of Vaud were alerted and immediately cordoned off the area around the scene. No persons were injured. TSCNET shareholder Swissgrid, the Swiss transmission system operator (TSO), disconnected and grounded the two 220kV lines affected by the collapse of the pylon, Banlieue Ouest-Foretaille and Crans-Romanel. Grid stability is guaranteed and there are no supply failures in the Swiss transmission system.

Initial findings indicate that the pylon was subject to an act of sabotage, probably with the help of explosives. On-site investigations have been carried out by the Vaud Cantonal Police and the Swiss Federal Office of Police (Fedpol) while a criminal investigation has been opened by the Office of the Attorney General of Switzerland.

A 220kV pylon of Swissgrid has collapsed after an act of sabotage (picture: Canton de Vaud)

Linkup
> See Swissgrid news release, in German (html)
> See Media release of the Cantonal Police of Vaud, in French (html)

See article on single page

Redispatch harmonisation in Germany

26.06.2020

Up until now, redispatch measures between the four German transmission system operators (TSOs) – 50Hertz, Amprion, TenneT, and TransnetBW – and the operators of power plants and storage facilities with a capacity of more than 10MW have been carried out on the basis of IT tools specific to the particular TSO control area. In order to align the individual procedures nationwide, the four TSCNET shareholders on 26 June successfully put the first component of their joint redispatch platform into operation, the “Redispatch Settlement Server” (“Redispatch-Abwicklungsserver” – RAS).

The German electricity market is increasingly characterised by volatile generation and RAS is an instrument to initiate redispatch measures both faster and more flexibly. With harmonised data formats and processes, the redispatch platform, of which the RAS is the first part, provides the basis for the integration of renewable energies into the existing redispatch processes, that is, for future-proof congestion management. In concrete terms, RAS allows TSO control centres to monitor and process all relevant power plant interventions. As a result, TSOs can coordinate their redispatch decisions and activities more efficiently. Moreover, the central management introduces frictionless settlement and transparency processes.

The second part of the redispatch platform is the “Redispatch Determination Server” (“Redispatch-Ermittlungsserver” – RES). RES will complement or replace existing forecasting tools for expectable grid situations such as imminent bottlenecks. It will identify those options for action that are compliant with the regulations and most cost-efficient. Based on RES calculations, TSOs can resolve both predicted and existing grid congestions more efficiently than today. RES is scheduled to go into operation in 2021.

The four German TSOs have succesfully launched RAS, a joint server for redispatch settlement

Linkup
> See 50Hertz press release (html)
> See Amprion press release, in German (html)
> See TenneT press release, in German (html)
> See TransnetBW press release, in German (html)

See article on single page

Amprion Market Report shows encouraging trends

27.05.2020

The intermeshed European electricity market today requires constructive cooperation between all actors and organisations. Amprion, one of the four German transmission system operators (TSOs), considers the efficiency of cooperation at European level a key prerequisite for continental security of supply and the success of the energy transition. For this reason, the TSCNET shareholder was and is involved in numerous regional and European initiatives on system operation, network planning, and market integration. Also, Amprion is an observant analyser of the European market development, especially in the Central Western Europe (CWE) region and annually provides the Market Report for the CWE countries. The 2020 edition for the period 2015 to 2019 has just been released.

The Market Report is based on data from Flow-Based Market Coupling (FBMC) introduced by the six CWE countries (Austria, Belgium, France, Germany, Luxembourg, the Netherlands, and Belgium) in May 2015. By involving the entire regional network in the coupling of electricity markets, FBMC allows TSOs to allocate cross-border capacity and maximise market efficiency without jeopardising grid stability. The Amprion report clearly indicates the progress of the CWE market integration, especially with the following figures: In 2019, price convergence on the day-ahead markets increased by a further 10%, reaching 42%. In other words, in almost every second hour, day-ahead prices in the CWE have been equal because the TSOs succeeded in making sufficient power transmission capacity available to meet the demand of the entire region at the same prices.

Dr. Hans-Jürgen Brick, CEO of Amprion, comments on the positive development: “The Market Report furnishes proof that trade barriers could be decreased during the course of 2019.” Dr Brick places particular emphasis on the efficient and highly interconnected power grids in the CWE region and their “key role in ensuring Europe’s stable and secure energy system”. As regards Amprion’s individual contribution, the TSO was able to further improve the efficiency of its grid and thus strengthen European electricity trading. Whereas in 2018 the share of all active trade constraints caused by Amprion internal elements was 13.7%, in 2019 it was only 7.8%. This is due not only to the ongoing grid expansion measures, but also to the monitoring of overhead lines, which allows more efficient utilisation of the most important power lines.

Amprion has published the Market Report 2020 for the CWE region (picture: Daniel Schumann / Amprion)

Linkup
> See Amprion press release, in German (html)
> Open Amprion market report (pdf, 6.97MB)
> Open Amprion market report summary, in German (pdf, 524.8kB)

See article on single page

Minor power failure, major solution

29.04.2020

Only 16 minutes long was the power outage, and it affected only part of the state of Salzburg, but for the Austrian transmission system operator (TSO) APG, the small event was nevertheless related to a much bigger project. The Salzburg Line (“Salzburgleitung”) is a 380kv overhead line project of the TSCNET shareholder. The aim is not only to integrate increasing amounts of renewable energy into the grid, but also to ensure the long-term security of electricity supply for the Salzburg region and the whole of Austria. The line is a key factor in meeting #mission2030, the Austrian energy and climate strategy, which sets the national goal of covering 100% of electricity consumption with renewable energies by 2030.

The current incident has unexpectedly confirmed the necessity of building a new transmission line: Due to a technical defect, the grid coupling of the APG high-voltage grid at the Kaprun substation to the 110kV grid of Salzburg was interrupted, which led to a power outage. Thanks to the swift action of the APG experts, the connection was restored after only a good quarter of an hour. The incident had no critical consequences, but it clearly shows how important additional grid support for the Salzburg distribution grid through the new 380kV line and the new Pongau substation is.

A short-term power outage in the Austrian state of Salzburg underscored the importance of the planned Salzburg Line for grid stability (edited picture of Bruck near Kaprun: Kassandro, Creative Commons)

Linkup
> See APG press release, in German (html)

See article on single page