The Heat Trust has called for support for 500,000 households living on communal and district heating networks.
The consumer champion for heat networks has written to energy minister Lord Callanan calling for an urgent extension of the Energy Bill Discount Scheme (EBDS).
The scheme came to an end on 31 March, which the Heat Trust claims leaves “families exposed to unrestricted prices dictated by the wholesale gas market”.
Households living on communal and district heating networks are currently excluded from any protection created by the price cap.
The EBDS was created to provide equivalent support.
Stephen Knight, director of Heat Trust, said: “When the Energy Bill Discount Scheme was launched, the government said that it would ensure heat network customers would not face disproportionately higher energy bills than other households.
“Sadly, for many of the country’s 500,000 heat network customers, this has not been the case.
“While most households are finally now seeing their energy bills falling, many families in homes supplied by heat networks are still experiencing much higher prices as they remain unprotected by the price cap and pay for heat based on the historic wholesale cost of gas.
“We have called on the government to urgently extend the scheme for a further year to ensure that help reaches more heat network customers in need of support.
“At the very least, we need to ensure that everyone entitled to support in 2023-24 receives the money that they are entitled to, and that enforcement action is taken against suppliers who have failed to apply on behalf of their customers.”
Government data on payments made to energy suppliers under the EBDS scheme show that less than 15% of the originally allocated £380 million had been spent after 10 of the 12 months of the year.
This data also suggests that only around 2,550 heat networks had their electricity and gas costs supported, out of the 9,000 plus UK heat networks with domestic customers.