The cost of decarbonising UK public sector buildings is estimated to be £25-30bn, government figures show.
The amount was revealed following a Freedom of Information request by the Sunday with Laura Kuenssberg show.
The government said the “indicative” figure is based on today’s prices and should not be seen as the actual budget needed to move to low carbon heating.
Transitioning from fossil fuel heating systems is one way the UK can meet its aim of net zero CO2 emissions by 2050.
The government has set a target of reducing greenhouse gas emissions from public buildings by 75% by 2037 as part of its net zero strategy.