ACM publishes roadmap with its preparations for the Dutch Collective Heat Act
The Netherlands Authority for Consumers and Markets (ACM) has published a roadmap outlining milestones in its preparations for the Dutch Collective Heat Act (in Dutch: Wet collectieve warmte, or Wcw). This new law will replace the Dutch Heat Act (in Dutch: Warmtewet), and is expected to come into effect on January 1, 2027. ACM ensures that heat companies do not earn unreasonable financial returns from the supply of heat, and, each year, sets the maximum prices for heat. In addition, ACM ensures that heat companies set reasonable conditions, and that they are financially, organizationally, and technically able to supply heat to households in a reliable manner. The roadmap outlines what steps ACM will take in order to be ready in time for the new law, and it offers heat companies, consumer organizations, and other stakeholders insight into the schedule and the moments in time at which they are able to give input.
ACM works on multiple fronts preparing for the Dutch Collective Heat Act. First, ACM is preparing for the cost-based tariff regulation, including the method decision and a decision on reasonable returns (WACC). In that context, ACM will draw up new regulatory accounting rules (RAR), so that heat companies submit financial data correctly and in such a manner that this data can be compared. ACM is also developing a method for determining the standardized asset value (in Dutch: gestandaardiseerde activawaarde, GAW), the regulatory value of heat networks, which serves as the basis for calculating cost-based tariffs. In addition to tariff regulation, ACM is also preparing for its monitoring of the stability of heat suppliers. In the Dutch Collective Heat Act, the current licensing assessment will be replaced with a competency review. Also, ACM will be charged with new duties regarding financial monitoring and security of supply.
Tariff regulation under the Dutch Collective Heat Act
One important change under the Dutch Collective Heat Act is the transition from the current ‘no-more-than-otherwise’ principle (in Dutch: Niet-meer-dan-anders-principe, or NMDA), to tariffs based on the actual costs of heat networks. This transition will take place in three phases. The first phase, in which the link to the natural-gas price will be corrected on a few points, will start when the Dutch Collective Heat Act comes into effect on January 1, 2027. In the second phase, ACM will set the tariffs for large collective systems with more than 1,500 users on the basis of the efficient costs per plot. For small collective systems with fewer than 1,500 users, ACM will set the tariffs on the basis of a cost-based reference. The Dutch House of Representatives will decide whether phase two of the tariff regulation will take place. In the run-up to that decision, ACM will advise the minister on the matter. This means that ACM will set the heat tariffs using the natural-gas price (NMDA) until at least 2030. However, during that period, ACM will make preparations for the cost-based tariff regulation. In the third phase of the tariff regulation, ACM will set the tariffs for large collective systems on the basis of the allowed revenues for that specific heat network. This phase will begin in 2034 at the earliest.
Key moments for stakeholders
The Dutch Collective Heat Act will come into effect on January 1, 2027, but its full implementation will span several years. In the coming months, ACM will organize various consultations and sounding-board groups. On March 31, a sounding-board group meeting was held for heat companies regarding ACM’s preparations for the competency review and the cost-based tariff regulation. On April 16, 2026, a sounding-board group meeting on the same topics will be held for municipalities. Consultation on the new RAR will begin in the spring of 2026, followed by their publication in the summer of 2026. A consultation on the GAW method will take place in mid-2026, after which the method will be finalized in late 2026. The first individual GAW decisions will follow in 2027-2028. Starting in the spring of 2026, sounding-board group meetings will be held regularly in which the cost-based tariff regulation will be worked out.
Consumer organizations, user organizations, heat companies, and other stakeholders are able to consult the timeline with milestones on ACM’s website. There, they will also find the full schedule, and see when they will be able to provide input.