RHI scheme - what was it?published at 09:23 Greenwich Mean Time 17 November 2017
The Renewable Heat Incentive scheme - or RHI for short - came to the fore of the Northern Ireland public's knowledge in autumn last year.
Few people, if anyone, would have expected it to have the consequences it has done in the months that followed.
It was set up by the Northern Ireland Executive in 2012, as a way of encouraging businesses to switch from using fossil fuels to renewable sources for generating their heat.
Those who signed up were offered financial incentives to buy new heating systems and the fuel to run them.