The organisers of a scheme to drill for 'hot rocks' at the former Blue Circle cement works in Eastgate, near Stanhope, have defended the work.
The drilling work is costing £460,000
The Weardale Taskforce is using £460,000 of European funding to search for hot granite, which could be used to heat around 4,000 homes.
But Durham county councillor John Shuttleworth said the plan is unlikely to succeed, or to create any jobs.
John Hamilton, the taskforce's chairman, says 150 jobs could result.
He said: "We've done lots of studies and research and we believe there is hot granite down there and hopefully water with it.
"It is risky, but if we don't try anything we won't get anywhere.
"The estimate is for 150 jobs on the Eastgate site - if we find the hot granite."
Mr Shuttleworth, who is also a member of the taskforce, said: "I'm very sceptical about the whole scenario.
"We're talking about public money to provide what is, I would suggest, nothing more than a publicity stunt.
"I think people are so sick of the cement works just standing derelict that it should be taken down immediately and just put to a better use.
"Hot rocks are not going to create jobs for people in Weardale."
But Mr Hamilton said the scheme had the backing of residents.
He said: "We put this to the people, consulted with them and sent it round to every home. We got a good response and the project has an awful lot of supporters."
If the hot granite is found, planning applications will be submitted and construction of houses on the site could begin around 2007.
In the meantime, the site will be cleared and cement works knocked down, according to Mr Hamilton.