The latest Northern Ireland Audit Office (NIAO) report into the Province’s botched non-domestic Renewable Heat Incentive scheme shows that during the financial year 2016/17, the Department for the Economy and the Northern Ireland Executive had to underwrite the scheme to the tune of £27 million because the scheme was much more expensive to run than provided for by HM Treasury rules.

The department has introduced new regulations for 2017/18 so that the tiered rate and cap on heat output now applies to all users.

However, this is subject to a legal challenge.