Closed system tariffs under the Dutch Energy Act: what may the operator charge?

No, the operator of a closed system is not free to charge what it likes, even though the Netherlands Authority for Consumers and Markets (ACM) does not approve its tariffs in advance. Under Article 3.114 of the Dutch Energy Act (Energiewet), in force since 1 January 2026, the operator must publish a calculation method beforehand that leads to cost-reflective, transparent and non-discriminatory tariffs; any connected party can have the ACM test this through a complaint.

The statutory standard is only half the picture. A tariff also needs a clear contractual basis: without a clear payment clause in the connection and transport agreement, even a reasonable tariff is vulnerable in the civil courts. Our overview article on private networks and closed distribution systems sets out the wider regime.

What changed when the Energy Act replaced the Electricity Act 1998?

Until 1 January 2026, closed distribution systems operated under an exemption (ontheffing) based on Article 15 of the Electricity Act 1998. The Energy Act replaces the Electricity Act 1998 and the Gas Act and works with recognition (erkenning) of a closed system by the ACM under Article 3.7.

Existing exemption holders keep their position for now. Under Article 7.32 of the Energy Act, an owner that held an exemption under Article 15 of the Electricity Act 1998 is deemed to hold a recognition and an operator designation for as long as that exemption runs. Check the end date of your exemption and apply for recognition well before it expires.

The European basis is Article 38 of Directive (EU) 2019/944. It allows member states to exempt closed distribution systems from prior approval of tariffs, but not from the requirements of transparency and non-discrimination.

What does Article 3.114 of the Energy Act require?

The operator must charge a tariff set in line with a calculation method it has drawn up and published in advance. That method must lead to tariffs that reflect the costs of its statutory tasks and are transparent and non-discriminatory (Article 3.114(1)).

The standard has three elements:

• Published in advance: the operator cannot set tariffs retroactively or case by case; connected parties must know the method beforehand.
• Cost-reflective: tariffs follow the costs of the statutory tasks under paragraph 3.5.5 of the Energy Act, not the operator’s commercial goals.
• Transparent and non-discriminatory: the method is verifiable, and comparable connected parties pay comparable tariffs unless an objective difference justifies otherwise.

Within these three limits the operator may design a method that fits its site. If it ignores them, the ACM orders an adjustment under Article 3.114(2).

Which costs may the operator include in its tariffs?

The Act contains no list of eligible costs, but cost-reflectivity gives a workable test: only costs connected with the statutory system-operator tasks belong in the tariff. Costs of other business activities, or costs already recovered through rent or service charges on the site, do not.

Costs that usually qualify are:

• connections and changes to connections;
• operation, maintenance, control and metering of the system;
• the charges the operator pays to the public grid operator for the transfer point;
• a reasonable, attributable share of general overhead.

Article 4.10 of the Energy Act allows the operator to use data from its connection register for determining tariffs and performing connection and transport agreements. The separate-accounts duty of Article 3.42 of the Energy Decree (Energiebesluit) applies to public transmission and distribution system operators, not to closed-system operators. Even so, a closed-system operator must be able to show how each cost item was calculated: what it cannot substantiate in an ACM complaint, it cannot charge.

Why does the tariff clause in the contract matter so much?

A tariff is only payable if the agreement clearly provides for it. The ‘s-Hertogenbosch Court of Appeal held that a supply agreement gave no basis for a periodic connection charge because the payment obligation was not clear from the contract documents (ECLI:NL:GHSHE:2024:2263); the Supreme Court upheld that judgment (ECLI:NL:HR:2026:94).

That case concerned heat supply, but the lesson applies to closed systems. Record what each amount is for, how it is calculated, and whether it relates to connection, maintenance, transport or metering. When a clause is unclear, the court interprets it by what the parties could reasonably expect from each other, and that interpretation can go against the operator.

Can a tariff clause in general terms and conditions be annulled?

A clause in general terms and conditions that is unreasonably onerous is voidable under Article 6:233 of the Dutch Civil Code (BW). However, under Article 6:235 BW a connected party that publishes annual accounts or employs 50 or more people cannot invoke that ground, which excludes many industrial users on a closed site.

The rule that the interpretation most favourable to the other party prevails (Article 6:238(2) BW) applies only to consumer contracts. On a business site, the content of the clause itself must therefore carry the weight: allocation keys, indexation, treatment of reinforcement investments and the information the connected party receives each year.

Does the operator have to arrange separate connections or EAN codes?

Not automatically. The Arnhem-Leeuwarden Court of Appeal held that a private network operator must respect the connected parties’ free choice of supplier, but that this does not in itself oblige it to arrange an EAN code or a separate connection (ECLI:NL:GHARL:2026:316).

How does a complaint to the ACM work?

A connected party with a dispute about how the operator performs its statutory tasks can file a complaint with the ACM under Article 5.4 of the Energy Act. The ACM decides within two months; it can extend that period once by two months if it requests additional information, and longer with the complainant’s consent.

The ACM’s decision is binding (Article 5.4(3)). If the ACM finds that the calculation method or a tariff does not meet Article 3.114(1), it orders the operator to adjust it. A complaint does not affect your other legal remedies, such as a civil claim for repayment (Article 5.4(4)).

The ACM tailors its review to the tasks, the characteristics of the system and the cost substantiation; it does not simply copy the tariff regulation for public grid operators. For connected parties with a small connection, the operator must also offer a transparent, simple and inexpensive complaints procedure (Article 3.34 of the Energy Decree).

Which tariff disputes arise most often?

Three situations cause most disputes, and the Energy Act leaves all three to the contract and the calculation method:

• Reinforcement for one user: who pays when the system must be reinforced for the growth or electrification of a single connected party?
• A large user leaves: do the fixed costs shift to the remaining connected parties, or does the operator bear that risk?
• A newcomer joins: on what terms does a new party get access, and does it contribute to past investments?

Settle these scenarios in advance; otherwise they end up in an ACM complaint under Article 5.4 or in civil proceedings.

What should you check as a closed-system operator?

• Is your calculation method written down and published to all connected parties before you apply it?
• Can you trace every tariff component to a cost of your statutory tasks?
• Do your connection and transport agreements contain a clear payment clause, allocation key and indexation rule?
• Does your old Article 15 exemption still run, and when must you apply for recognition under Article 3.7?
• Do you offer small connected parties a complaints procedure that meets Article 3.34 of the Energy Decree?

What should you check as a connected party?

• Have you received the published calculation method, and do your invoices follow it?
• Does your agreement clearly state what each charge is for and how it is revised?
• Are costs you already pay through rent or service charges charged again in the tariff?
• Are comparable users on the site paying comparable tariffs?
• Have you raised objections in writing before filing a complaint with the ACM under Article 5.4?

What can we do for you with closed-system tariffs?

Our energy lawyers act for operators and connected parties, before the ACM and the civil courts.

• We review your calculation method against Article 3.114 of the Energy Act.
• We draft or revise the tariff clauses in connection and transport agreements.
• We assess whether a charged tariff has a valid contractual basis and calculate what may be reclaimed.
• We prepare and file a complaint with the ACM, or defend the operator in the complaint procedure.
• We prepare the recognition application under Article 3.7 for operators whose old exemption is ending.

Summary

• The ACM does not approve closed-system tariffs in advance, but Article 3.114 of the Energy Act requires a published, cost-reflective, transparent and non-discriminatory calculation method.
• Only costs of the statutory system-operator tasks belong in the tariff.
• Without a clear contractual payment clause, a tariff is vulnerable in the civil courts.
• Any connected party can complain to the ACM under Article 5.4; the ACM decides within two months and its decision is binding.
• Old Electricity Act exemptions count as recognition only for their remaining term (Article 7.32 Energy Act).

Frequently asked questions