Introduction
The continuously growing demand for transmission capacity (transportcapaciteit) for both the take-off and feed-in of electricity,[1] driven by the energy transition, has pushed both the national high-voltage transmission system and the regional distribution systems[2] (together referred to as: the grid) in the Netherlands to their limits. This has resulted in widespread congestion and, consequently, the unavailability of transmission capacity in many parts of country.[3] To address this issue, the Netherlands Authority for Consumers and Markets (Autoriteit Consument & Markt, ACM), the national energy regulator, has introduced a multitude of measures aimed at preventing or alleviating the problems associated with grid congestion.[4] These measures are primarily intended to promote the efficient utilisation of the grid by ensuring that large-scale users (i.e., users with an electricity connection of more than 3×80 amperes) with flexible energy needs benefit from using the grid less or not at all during peak hours (often between 06:00 – 09:00 a.m. and 4:00 – 08:00 p.m.).
The problem of grid congestion predominantly occurs during peak hours, when there is more demand for transmission capacity (for take-off, feed-in, or both) than the grid can safely handle. During non-peak hours, however, there is often transmission capacity that is unused. This capacity is referred to as ‘residual capacity’ (restcapaciteit). One of the abovementioned measures to stimulate efficient use of the grid introduced by the ACM are so-called ‘alternative transmission rights’ (alternatieve transportrechten, ATRs), which are intended to utilise this unused residual capacity.
This blog discusses the concept of ATRs (what they are and what they are not), the different types of ATRs currently available or set to become available by 2025, and potential future developments regarding ATRs.
The concept of alternative transmission rights
What are firm transmission rights?
A transmission right (transportrecht) is a contractual agreement between the user and the transmission or distribution system operator (together referred to as: system operators) that grants the user the ability to access a certain amount of transmission capacity to transmit electricity for the purposes of take-off, feed-in, or both.
Until January 2024, system operators have only been able to allocate transmission capacity by offering transmission agreements with so-called ‘firm transmission rights’ (vaste transportrechten). With a firm transmission right, a user is fully entitled to the contracted transmission capacity at all times, throughout the entire contract period. Firm transmission rights provide certainty to users but are also inflexible, in the sense that even if the contracted firm transmission capacity is not fully utilised, this unused capacity remains unavailable to other users, resulting in inefficient use of (scarce) transmission capacity.
What are alternative transmission rights?
ATRs are alternatives to the aforementioned firm transmission rights and offer a more flexible approach to transmission capacity allocation by allowing transmission capacity (for take-off, feed-in, or both) to be assigned temporarily, partially, or conditionally to users. While a user with a firm transmission right is fully entitled to the contracted transmission capacity, this is not, or only partially, the case with ATRs. With an ATR, the user is not always entitled to the contracted transmission capacity, as the transmission right is (partially) ‘non-firm.’ This limitation is offset by a reduced transmission tariff.
The goal of ATRs is to achieve better utilisation of existing grid capacity and alleviate congestion problems by allowing users to arrange their electricity use in a flexible manner by contracting (part of) their transmission capacity on the basis of an ATR (instead of a firm transmission right). This frees up more grid capacity during peak hours, which can benefit users with no or less flexible grid use (i.e., users that require unrestricted access to contracted transmission capacity at any given time).
It is important to emphasise that ATRs are full-fledged transmission rights alongside the ‘classic’ firm transmission rights. As such, the same fundamental rights and obligations apply to users and system operators with regard to ATRs as with their firm counterpart. Most importantly, as with an application for a firm transmission right, system operators may refuse a user’s application for an ATR if the requested transmission capacity is not available (in the context of ATRs, this means that there is insufficient residual capacity available on the relevant part of the grid). Like their firm counterpart, ARTs are usually allocated on a first-come, first-served basis, and applicants who are not granted an ATR are placed on a waiting list.
Relationship with congestion management
It is important to distinguish ATRs from congestion management instruments, such as capacity restriction products (CRPs).
Congestion management is a response to grid conditions where, without further interventions, load flows are expected to exceed the safety margins of the infrastructure. In the Netherlands, large parts of the grid are already congested, and different solutions can be applied at various timescales to address this. Congestion management often involves financial incentives to temporarily reduce grid load by influencing user behaviour during peak hours. As such, it is reactive, addressing immediate or short-term imbalances in the take-off and/or feed-in of electricity. In this context, CRPs are often applied to ensure the stability of the grid by restricting the maximum allowable capacity that a user can access during certain period, thereby mitigating the risk of grid failures.
Unlike congestion management, ATRs are not tools for ad-hoc interventions, but are structural, long-term solutions, aimed at ensuring that available transmission capacity is utilised more effectively in the long-term rather than addressing immediate or short-term congestion issues. As such, ATRs are distinguished from congestion management instruments by their proactive, structured nature.
With respect to the relationship between ATRs and congestion management, it is important to emphasise that ATRs are to be regarded as addition to the existing tools already offered to system operators to utilise the grid more efficiently, such as congestion management. System operators are thus not relieved of their obligation to apply congestion management. By extent hereof, users with ATRs may be required by their respective system operator to participate in congestion management by offering CRPs. The obligation to do so is nevertheless limited to the extent that transmission capacity has been made available on the basis of the ATR.
Different types of alternative transmission rights
There are different types of ATRs, each with specific conditions, applicability, and benefits for certain users. By the end of 2025, transmission rights will have four forms:
- Firm transmission right;
- Fully variable transmission right (volledig variabel transportrecht);
- Time-block bound transmission right (tijdsblokgebonden transportrecht, TBTR); and
- Time-limited transmission right (tijdsduurgebonden transportrecht, TDTR).
The abovementioned transmission rights can be contracted separately or, if available, in combination with one another, and for either take-off or feed-in transmission capacity, or both.
The following paragraphs elaborate on the different types of ATRs, their applications, and how they benefit specific types of users.
Fully variable transmission right
Since 31 January 2024,[5] system operators may provide large-scale users with a fully variable transmission right, also referred to as a ‘non-firm connection and transmission agreement’ (non-firm aansluit- en transportovereenkomst, non-firm ATO).
A non-firm ATO gives the user the right use the grid during hours when sufficient residual capacity is available. This transmission right does not provide any predetermined guarantees concerning the availability of transmission capacity. The system operator informs users at least one day in advance about when and how much transmission capacity they can use. Because of this uncertainty, the transmission tariff for the delivery of electricity for a non-firm ATO is approximately 50% lower than that for a firm transmission right.[6] While the non-firm ATO has been available on a voluntary basis since the beginning of 2024 on both the transmission and distribution grids, as from 1 February 2025, system operators are obligated to offer users a non-firm ATO. Due to the nature of the non-firm ATO, this obligation applies irrespective of the (un)availability of residual capacity.
The non-firm ATO is intended primarily for users who can adapt their electricity use according to available transmission capacity, such as industrial consumers with flexible operations or users with a backup electricity supply. These users, in many cases likely awaiting the availability of firm transmission rights, may apply for a non-firm ATO as an interim measure, allowing them to hopefully partially carry out their business operations. Once firm transmission capacity becomes available, a non-firm ATO can be converted into a transmission agreement with a firm transmission right, at which point the user will start paying 100% of the transmission tariff.[7] A non-firm ATO is currently only available to users located in (impending) congestion areas (i.e., areas for which the system operator anticipates a shortage of transmission capacity within 12 months or areas for which a pre-announcement for congestion has already been made).[8]
Time-block bound transmission right
As of 1 April 2025,[9] distribution system operators are required to provide large-scale users with a time-block bound transmission right (tijdsblokgebonden transportrecht, TBTR) if there is sufficient residual capacity.
A TBTR grants the user access to grid capacity during specified time blocks within a day (aligned with non-peak hours). The system operator determines the applicable time-blocks based on grid calculations to ensure that peak loads are not exceeded. A TBTR offers guaranteed transmission capacity during these pre-defined time-blocks. Outside of these time-blocks, the user has no transmission rights. Due to the restricted times frames of grid access, a TBTR provides users with a lower transmission tariff.
The TBTR is particularly useful for users with predictable energy needs during off-peak hours who are able to plan their electricity needs, such as electric vehicle operators charging during the night or industries that need capacity only during certain times. Different from the non-firm ATO, the TBTR is available to users located in both congestion and non-congestion areas.
Time-limited transmission right
From 1 April 2025, the transmission system operator may voluntarily provide large-scale users with a time-limited transmission right (tijdsduurgebonden transportrecht, TDTR) provided there is sufficient residual capacity. As of 1 October 2025, the voluntary aspect is removed and a TDTR must be granted if there is sufficient residual capacity.
A TDTR allows users to access grid capacity for a specified number of hours annually, excluding certain peak periods where the network operator may limit capacity. More specifically, users are at least entitled to the contracted transmission capacity for at least 85% of the hours in a year (i.e., 7.446 hours). A TDTR provides a significant cost benefit compared to firm transmission rights, with a transmission tariff reduction of up to 50%. The trade-off is that, for the remaining 15% of the year, the user has no certainty about the availability of transmission capacity and does not know in advance exactly which hours of the year transmission capacity will be limited. If the situation on the grid requires a limitation of the transmission capacity, the transmission system operator informs the user of this one day in advance. Depending on the daily available residual capacity, the actual constraint may in practice also be less than 15% per year, but never more. The actual residual capacity allocated to a user with a TDTR on a daily basis may therefore be more favourable than at least 85% of the year, seeing that the transmission system operator will only limit the contracted transmission capacity if, based on daily forecasts, it expects no residual capacity to be available for the next day.
The TDTR particularly well-suited for users employing demand response and electricity storage providers with a connection to the transmission system, who in most cases do not need continuous, year-round access to transmission capacity and can match their operators to match transmission capacity availability. As with the TBTR, the TDTR is available to users located in congestion as well as non-congestion areas.
Conclusion and outlook
Over the course of last year, the ACM has introduced a wide array of measures aimed at mitigating congestion problems faced by both system operators and their users. These measures include the introductions of ATRs, which aim to utilise the grid more efficiently by making unused transmission capacity available to users with flexible energy needs. Each ATR offers distinct benefits and caters to different types of users with different types and levels of flexibility.
A non-firm ATO, which offers no guarantee for transmission capacity at all, provides flexibility for users located in (impeding) congestion areas, who may or may not be awaiting the availability of firm transmission capacity, who can adjust their energy use according to grid conditions. A TBTR, which guarantees transmission capacity during specific time-blocks, is particularly interesting for users with predictable and plannable energy needs, while a TDTR, which guarantees transmission capacity for at least 85% of the year, is suited for users that do not necessarily require round-the-clock access to their contracted transmission capacity.
Expansion of availability
While ATRs may provide a useful ‘tool’ for system operators to alleviate congestion problems and a welcome addition to the ‘traditional’ firm transmission right for users with flexible energy needs, their applicability is currently restricted in several ways.
As mentioned, the TBTR will for the time being only be offered on the regional distribution systems, whereas the TDTR will be made available only on the national transmission system. Furthermore, ATRs are currently not available to small-scale users (i.e. users with an electricity of less than 3×80 amperes), and based on remarks by the ACM, this is unlikely to change in the foreseeable future.
Energy-volume bound transmission right
In addition to the three ATRs discussed above, the ACM has granted distribution system operator Liander permission to experiment with a fourth type of ATR: an energy-volume bound transmission right (energie-volumegebonden transportrecht). This type of ATR allows users to contract a transmission right for a specific daily energy-volume (in kilowatt-hour (kWh)), rather than a transmission right solely pertaining to transmission capacity (in kilowatt (kW)). It is currently unclear if and when the energy-volume bound transmission right will become available.
Group transmission agreements
Like transmission agreements for firm transmission rights, transmission agreements for ATRs are necessarily concluded between a single user and its respective system operator. As part of the National Grid Congestion Action Programme (Landelijk Actieprogramma Netcongestie), the Dutch trade association of system operators (Netbeheer Nederland), recently proposed a Code amendment catering for the possibility for system operators to offer a group transmission agreement (groepstransportovereenkomst, Group-TA).[10]
Under a Group-TA, agreements between the system operator and a group of users are made regarding the joint allocation of transmission capacity, to be divided among the group of users. The individual users of the group relinquish their individual transmission rights and take collective responsibility for managing the allocated transmission capacity. This encourages transmission capacity usage among users being spread out, leading to a flatter demand profile and (more) optimal grid efficiency.
Pursuant to the proposed Code amendment, Group-TAs will be available only for firm and fully variable transmission rights. A Group-TA can include users with firm transmission rights, non-firm ATOs, or a mix of both. In the latter case, users of the group benefit from possibility to collectively optimise and balance their energy needs by combining or interchanging the use of residual capacity (on the basis of non-firm ATOs) with transmission capacity during peak hours (on the basis of firm transmission rights).
If you have any questions regarding alternative transmission rights, please feel free to reach out.
[1] ‘Take-off’ (levering) of electricity refers to the delivery of electricity from the transmission or distribution system to a user, while ‘feed-in’ (teruglevering) of electricity refers to the feeding of generated electricity back into the transmission or distribution system by a user.
[2] The electricity grid in the Netherlands consists of the national transmission system (transmissiesysteem voor elektriciteit), which is used for the transmission of electricity at voltage levels above 110 kilovolts and is operated by the national transmission system operator (transmissiesysteembeheerder) TenneT TSO B.V., as well as several regional distribution systems (distributiesystemen voor elektriciteit), which are used for the transmission of electricity at voltage levels below 110 kilovolts and, depending on the location of the electricity connection, are operated by one of six distribution system operators (distributiesysteembeheerders).
[3] In short, congestion occurs when the demand for electricity transmission exceeds the available capacity of the existing grid. In such a case, granting the desired transmission capacity would cause the load on the grid infrastructure to surpass its (statutory) safety limits. A given area may experience take-off congestion, feed-in congestion, or both.
[4] An overview of the various measures that have been or will be implemented by the ACM to alleviate congestion problems was published on 25 November 2024 and can be found here (in Dutch).
[5] The Code decision of the ACM of 25 January 2024 regarding the non-firm ATO can be found here (in Dutch).
[6] Currently, there is no transmission tariff for the feed-in of electricity to the grid (a so-called ‘feed-in tariff’).
[7] Once an ATR is converted into a firm transmission right, the respective user will start contributing to grid capacity expansion investments incurred by the system operator.
[8] A non-firm ATO is not available in non-congestion areas because a non-firm ATO within a congestion area is a product with a different effect than a non-firm ATO outside a congestion area. In a congestion area, a user with a non-firm ATO is granted transmission capacity only when this capacity, despite congestion, is available. Conversely, in a non-congestion area, the desired transmission capacity would always be available since in such an area there is, by definition, sufficient capacity on the grid. This latter situation does not justify a reduced transmission tariff for a non-firm ATO.
[9] The Code decision of the ACM of 16 July 2024 regarding ATRs can be found here (in Dutch).
[10] The proposal for a Code amendment by Netbeheer Nederland of 24 October 2024 regarding the Group-TA can be found here (in Dutch).
