Our key tasks

We are primarily tasked with providing power transmission services, system services and facilitating the energy market. Our core tasks follow from our appointment as grid operator under the Dutch 'Elektriciteitswet' (E-wet) and the German 'Energiewirtschaftsgesetz' (EnWG).

 

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Innovation

TenneT presents Hub and Spoke concept for large scale wind energy on the North Sea.

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Our grid

TenneT manages the high-voltage grid in the Netherlands and large parts of Germany. TenneT transmits electricity at 110,000 volts (110 kV) and higher. With over 22,500 kilometres of high-voltage lines, we cross borders and connect countries.

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Grid maps

Maps of our onshore and offshore high-voltage grid.

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Electricity market

The energy sector is developing rapidly. The process of European market integration began some years ago. Its purpose is to create a single European market that enables market parties to trade gas and electricity across national borders easily and efficiently.

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Transparency data

We provide transparency data on our operations on our Dutch and German transparency page and on ENTSO-E. 

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E-Insights

Our vision is to be one of the most transparent Transmission System Operators (TSO) in Europe and thereby creating value for society. In this Energy Insights section we present selected energy related topics and show data, information and valuable insights. 

E-Insights

E-Insights

Facts & figures related to TenneT facilitating the market can be found here.

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Company

TenneT is a leading European electricity transmission system operator (TSO), with activities in the Netherlands and in Germany. We strive to ensure a reliable and uninterrupted supply of electricity in our high-voltage grid for some 41 million people.

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We are TenneT

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Ancillary Services

TenneT's main tasks are providing transport services, providing system services, providing a connection service and facilitating the energy market. To provide these system and transport services, TenneT uses ancillary services offered by the market.

Ancillary Services

Directive 2009/72/EC defines "ancillary service" as: a service necessary for the operation of a transmission or distribution system;

These are services provided by users of the transmission or distribution system to the TSO or DSO for operating the transmission or distribution system.

TenneT uses these ancillary services for various purposes in accordance with its regulated tasks and obligations as a TSO. These ancillary services include:

  • Balancing reserves
  • Reactive power
  • Redispatch
  • Black start facility
  • Compensation of losses and sustainability of grid losses through Guarantees of Origin (GoOs)

International and national law prescribes the conditions under which an ancillary service is mandatory or voluntary and whether it should be paid or unpaid. In addition, users of transmission and distribution systems are legally obliged to comply with the requirements of the TSO and / or DSO for these services (including financial settlement of imbalance with the TSO).

TenneT procurers many of the necessary ancillary services regularly in the market. More information about the procurement process can be found here.

Balancing reserves

Frequency Containment Reserves (FCR)

FCR (primary reserve power) is the power that is activated under the control of the primary regulation. The primary control is a locally designed automatic device, which ensures a constant ratio between frequency change and installation (power) change within a maximum of 30 seconds. The aim of FCR is to stabilise frequency disturbances in the entire (internationally) connected high-voltage grid, regardless of the cause and location of disruptions. Severe frequency disturbances can lead to automatic load shedding and in the worst case cause a blackout. ENTSO-e rules stipulate that the TSO must have a certain volume of FCR available. This volume is determined annually by ENTSO-e. It is because of this obligation that TenneT procures FCR.

Procurement process
TenneT organises two separate weekly auctions to purchase the FCR volumes it requires. One auction for Dutch suppliers only and one auction with other TSOs called "the common auction". To learn more about these auctions and the product FCR, read the following documents.

Frequency Restoration Reserves (aFRR)

For maintaining the real-time power balance of the Netherlands, TenneT mainly uses bids for regulating power (aFRR) and reserve power (mFRRsa) offered by market participants to TenneT. The activation (dispatching) of FRR bids for balancing takes place in real-time operations. This regulating and reserve power is exlusively for correcting the real-time power imbalance.

Procurement process
In order to ensure that sufficient bids of regulating power or aFRR is available at all times, TenneT enters into capacity contracts in which suppliers commit to making bids for a certain period. For this TenneT organises a monthly tender and a weekly tender. To know more about these tenders and the product aFRR read the following documents.

manual Frequency Restoration Reserves directly activated (mFRRda)

TenneT uses the regulating and reserve bids for maintaining balance that have been made available by market participants. In addition, TenneT can use mFRRda, or incident reserves, for maintaining the balance in case of incidents and substantial long-lasting power deviations.

Procurement process
Emergency power is contracted by TenneT at suppliers. The incident reserve supplier has the obligation, over the entire contract period, to be able to draw or supply the power agreed from the Dutch grid on call from TenneT. The emergency power is purchased per quarter and per month. Learn more about the product mFRRda then read the following documents.

manual Frequency Restoration Reserves scheduled activated (mFRRsa)

mFRRsa is reserve power that is used for balancing purposes. In contrast to aFRR, the bid has a call time of 1 PTU instead of a ramp rate. The call is the offered volume per PTU. These bids are not contracted. More about the format of the bids in the "implementation guide" and "Manual Bidding of Regulating and Reserve Power" (RRP).

Reactive power

The TSO must ensure adequate voltage control for the high-voltage grid. In order to so TenneT requests a supplier of reactive power to deliver or absorb reactive power at the point of grid connection at a level that differs from the standard exchange of 0 Mvar.

Procurement process
TenneT can enter into contracts with electricity producers that are connected to the EHV (380 kV / 220 kV) or the HV (150 kV / 110 kV) grid which put the reactive power range of each contracted production unit at TenneT's disposal. These contracts can apply for a specified period but also for a specified situation. The contracts are concluded following the outcome of a yearly tender.

To learn more about the product reactive power, read the following documents.

Redispatch

Redispatch (shifting in-feed and take-off of electricity from the grid) is one measure for solving expected transport problems (usually N-1 overload) in the high-voltage grid. By feeding in less power in one place and more (to the equivalent amount of) power in another place into in the grid, transports are influenced and transport problems can be solved.

For redispatch, TenneT can use the so-called "reserve power for other purposes" that are offered to TenneT.

Procurement process
Suppliers 'Reserve Power for Other Purposes' can submit bids to TenneT. These bids can, with the exception of the approval period, be adjusted to 3 Program Time Units (PTU's) before the PTU from start of delivery.

For more information about the product 'reserve power for other purposes' read the following documents.

TenneT performs redispatch when transport problems occur for which the solution is considered is shifting production. Because the location in the high-voltage grid where more or less energy needs to be fed-in is important, contact is initially sought with connected parties in the problem area. For this reason, unique bilateral contracts are concluded for redispatch with such parties. There is therefore no standard procedure for this.

Black start facility

One of the tasks of TenneT is to coordinate the restoration of electricity supply in the event of a black out. To be able to fulfill this task, TenneT requires facilities that can energise a grid and deliver power in a situation in which (a large part of) the actual grid voltage of national HV grid is equal to zero, in order to allow TenneT to restore the electricity supply. TenneT concludes a contract for the provision of a black start sevice only every so many years with contract period spanning multiple years because of the required investments.

A procedure to conclude a new agreement is announced well ahead of time.

Losses and sustainability

When electricity is transported a small share of this electricity is converted into heat. These so called grid losses are compensated by the TSO by procuring electricity.

TenneT distinguishes between the grid losses in the national AC-grid and the cable losses of the DC-cable to Norway (NorNed).

In addition TenneT procures Guarantees of Origin (GoO) corresponding to the volume of the grid losses.

Procurement process Grid losses (Extra) high voltage grid
The ancillary service requested  is the supply of electricty to compensate for total grid losses. This ancillary service is regarded as commodity to be  procured on an annual basis.

A tendering document is issued annually.

Procurement process Cable losses
Transmission of electricity on the NorNed cable also causes losses. These cable losses are taken into account using a fixed formula in the market coupling process. The resulting deficit or surplus is procured or sold separately. For these transactions a contract is concluded with a supplier on an annual basis. A document describing the requirements and specific way of working is drafted annually.

Procurment process Garantees of Origin (GoO)
In its capacity of TSO, TenneT procures the electricity that is necessary for a well-functioning system. This includes the compensation of grid losses and the cable losses Norned and the electricity consumption of converter stations. The source of this purchased electricity is not defined. However, to minimise the environmental impact of its own electricity consumption and to stimulate the production of renewable energy, TenneT procures Guarantees of Origin (GoO) based on an annual call for tender.

Systeem code electricity

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Related

System Operations Nederland

TenneT TSO B.V.'s taken bestaan o.a. uit het verzorgen van transportdiensten, het verzorgen van systeemdiensten en het faciliteren van de energiemarkt. U vindt hier informatie over de producten en diensten welke gebruikt en geleverd worden en de actuele data over het Nederlandse elektriciteitsnetwerk en het door TenneT TSO B.V. beheerde landelijk transportnet.

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Security of supply

A secure and continuous supply of electricity is the key objective of our operations.

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