Climate minister Rob Jetten is working on emergency legislation to limit the cost of city heating schemes to tenants and home owners, after it emerged some people are facing sharply higher bills after going gas-free, broadcaster NOS said on Friday.

“A collective heating system is the best alternative for gas central heating systems for around one-third of Dutch houses,” Jetten is quoted as saying. “We can make older houses more suitable as well but it is very important that the city heating schemes are CO2 neutral and that the cost to tenants and homeowners is acceptable.”

Some 500,000 homes in the Netherlands are currently kept warm via city heating schemes that use either specially generated heat or heat created in industrial processes or by waste incineration.

In current legislation, the cost of city heating is allowed to rise in line with gas prices, even though the homes are gas-free. In addition, tenants and home owners have no choice about which company to use.

In both Rotterdam and Amsterdam city heating providers have come under fire because of soaring costs to tenants and some housing corporations have halted projects to switch. The energy firms say this is due to the increased costs they face via subcontractors, staffing and equipment.

Some 90% of the country’s district heating networks are in private hands. Swedish-government owned Vattenfall, Eneco, which is part of Mitsubishi and Ennatuurlijk dominate the market.

Two years ago, Jetten said he was looking into partially privatising city heating firms and to delink the cost of city heating from gas prices.