NMDA stands for “niet meer dan anders” — no more than otherwise. It is the Dutch principle that a household connected to a heat network must not pay more for heat than a comparable household heating with a gas boiler. It underpins tariff regulation in the Dutch Heat Act.
How it works
Anyone connected to district heating cannot switch supplier — there is only one network. To protect these captive customers, the Dutch regulator ACM sets maximum tariffs each year for heat supplied to small consumers (connections up to 100 kW). Those caps are derived from what an average household with a gas boiler would pay for the same amount of heat: the so-called gas reference.
The comparison covers more than the gas itself. Fixed costs are included too:
- The standing charge and connection costs
- The cost of a gas boiler (purchase, servicing, depreciation)
- Energy tax on gas
What it means for residents
- A cap, not a fixed price — a supplier may charge less, and sometimes does
- Linked to the gas price — when gas prices rise, the maximum heat tariff rises with them
- No boiler costs — but the standing charge for heat is usually higher
Criticism and change
The gas reference is widely criticised: the costs of running a heat network have little to do with the price of gas, so tariffs and actual costs can drift apart. Newer Dutch legislation on collective heat aims to base tariffs on the actual costs of the network instead of the gas price. If you are weighing up a heat connection, check which regime applies at that moment.
Practical tip
When comparing district heating, never look at the variable rate per unit alone — add the fixed costs (standing charge, meter rental, heat interface unit). In a well-insulated home with low consumption, that fixed component makes up most of the annual bill.
Related terms
- Heat network
- District heating
- Energy tax
- Standing charge
- Heat pump
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