But one of his tenants said: “The slick PR will stick in the throat of many tenants.
“He should start by bringing the homes he already owns up to modern standards.”
The 700-year-old Duchy of Cornwall owns more than 600 rental properties.
William is managing the estate he inherited from his father in 2022, when Charles became King following the death of Queen Elizabeth II.
Last year he earned £24m from it, and since MEES regulations were introduced in 2020, William and his father have received £91m in profits from the estate.
Of almost 500 Duchy-owned properties, identified via the Land Registry, 50 were rated F and 20 were rated G – including six with the lowest EPC score of one point out of 100.
Tenants told of the press of the cold, poorly insulated homes, often without central heating, forcing them to rely on expensive solid fuels for warmth.
Claire Williams, 53, said she was forking out £200 a month on oil for a rented farmhouse near Exeter, Devon, but “all the heat is going out [the] windows”.
“I’ve complained about it for 21 years,” she said. “They don’t seem to have consideration for people.”
Told that she was being evicted for rent arrears – which she disputes – Williams rang Citizens Advice and says she then found out the house was rated F.
Williams added: “They said, ‘You shouldn’t be paying to live there and it’s illegal to let that property out’.”
Another tenant with no central heating spends hundreds a month on coal and wood to heat just two rooms.
The man, who asked to remain anonymous, told the press: “It gets miserably cold, especially in the winter.
“You can see through the roof. The landlord told me that my rent was going to be put up considerably if they put in radiators.
“There is mould appearing on soft furnishings and clothes.
“To make my property efficient it needs to be insulated but they won’t do that because of the cost. “But you don’t want to say anything against your landlord for fear of eviction.”
Another said: “The house is freezing. When the wind blows the curtains start swinging.
“I asked about double glazing and they said Prince Charles doesn’t like it.”
Breaches of the MEES regulations can be penalised with fines of up to £5,000 per property .
Jonathan Bean, of pressure group Fuel Poverty Action, said: “It’s a disgrace that a billion pound royal estate appears to be acting like a rogue landlord.”
