It's projected at €577m - but Foster insists green energy overspend 'will cost zero'
Arlene Foster insists the troubled green energy scheme tipped to cost Stormont some £500m will not cost the Northern taxpayer a penny.
In an interview with the 'Belfast Telegraph' the North's First Minister said detailed work had been carried out over Christmas to devise ways of cutting the cost of the Renewable Heating Incentive (RHI) scheme.
It currently has a projected overspend of £490m (€577m) over the next 20 years.
"A lot has been made about the potential overspend. I want to make sure that doesn't happen," she said.
"We plan to bring that potential cost down to zero. There will be no overspend."
It came as the UK government rejected a call to instigate a public inquiry into the scheme. It made clear the RHI controversy was a devolved issue for Belfast to deal with.
The escalating political row has edged the power-sharing institutions towards implosion.
The RHI was supposed to offer a proportion of the business cost to run eco-friendly boilers, but the subsidy tariffs were set too high, so it ended up paying out significantly more than the price of fuel.
Responding to Sinn Féin calls for her to stand aside, Ms Foster said: "I want an inquiry to go ahead and I want to get cost controls in place."