Timeline: Renewable Heat Incentive scandal
First Minister Arlene Foster has promised that every beneficiary of a botched energy scheme will be inspected for abuse of public money.
Serious flaws in the Renewable Heat Incentive (RHI), set up in 2012, could cost taxpayers £400m.
- The RHI is launched in Northern Ireland to help businesses, public sector, and other non-domestic organisations in Northern Ireland meet the cost of installing renewable heat technologies - therefore reducing the UK's carbon emissions.
- Tariffs are set by DETI.
- Eligible applicants are entitled to help for 20 years after accreditation.
- Whistleblower contacts DETI Minister Arlene Foster.
- A follow-up email is sent on 12 May 2014.
- The initiative is extended to the domestic sector.
- The Department of Trade and investment is due to seek re-approval of the scheme from the Department of Finance but this is overlooked due to a "combination of staff changes and an administrative oversight".
- Applications for the initiative increase.
- Whistleblowers allege RHI has overspent by millions.
- Industry Minister Jonathan Bell announces his intention to close the scheme to new applications.
- An investigation into the scheme gets underway.
- The Audit office says "serious systemic failings" would hit the Northern Ireland budget to the tune of hundreds of millions of pounds.
- There was no cap on the subsidy payments: The more heat you generated, the greater the subsidy you were paid.
- Economy Minister Simon Hamilton (DUP) says the ongoing costs of the scheme to taxpayers are "incredible".
- Senior members of Ofgem E-Serve appear before the assembly's Public Accounts Committee.
- They reveal there were no minutes taken of formal meetings between themselves and departmental officials between August 2014 and November the following year.
8 December 2016
- A whistleblower tells the BBC's Nolan Show that "five minutes" of research was needed to discover serious flaws in the RHI.
- She says she contacted Arlene Foster in 2013 to warn the then enterprise minister about the issue.
- SDLP leader Colum Eastwood calls on Mrs Foster to appear before the Public Accounts Committee.
12 December 2016
- Mrs Foster says she has "nothing to hide" in relation to the RHI.
- She announces that the executive will write to claimants to seek permission for their names to be made public in a bid to restore public confidence.
- Political opponents accuse Mrs Foster of shirking responsibility on the issue.
14 December 2016
- Senior sources tell the BBC Arlene Foster personally fought a decision by an executive colleague to close the scheme.
- The First and Deputy First Ministers ask for the Northern Ireland Assembly to be recalled to discuss the botched heat scheme.
15 December 2016
- In an exclusive interview with the BBC's Stephen Nolan, former DUP minister Jonathan Bell says advisers to Arlene Foster attempted to remove her name from documents linked to RHI.
- Mr Bell, who succeeded Mrs Foster as the minister of the department that set up the scheme, claims two top DUP advisers "were not allowing this scheme to be closed" at the point when costs were spiralling out of control in autumn 2015.
- Mrs Foster responds that if papers were altered "it wasn't on my say-so".
- The two advisers named by Mr Bell, Timothy Johnston and Dr Andrew Crawford, said they never sought to keep the RHI scheme open against the wishes of the minister, adding that their roles were simply "to offer advice" and not to "influence any decision".
21 December 2016
- The executive is reported to be considering complete closure of the RHI scheme. Buying out the recipients would incur a cost, but would reduce the final bill.
4 January 2017
- Arlene Foster again says she will not stand down over the RHI scandal, adding that some calls for her to do so are "misogynistic".
- Biomass boiler owners have formed a group to deal directly with government officials proposing changes to the scheme.
- Economy Minister Simon Hamilton is reported to be seeking Sinn Féin's approval for emergency legislation, which he says could reduce the projected £490m overspend to "zero".
- The DUP says the plan could be brought to the assembly next week if agreed by the executive.
- Sinn Féin Finance Minister Máirtín Ó Muilleoir says he is "bemused " by the DUP trailing the proposal in the media before speaking to him.
5 January 2017
- Former DUP MLA David McIlveen criticises Mrs Foster for what he describes as the RHI "omnishambles". He says she has "seriously misjudged" public anger.
- Sinn Féin leader Gerry Adams says the political institutions have reached "a defining point" over the first minister's refusal to step aside.
9 January 2017
- Martin McGuinness resigns as deputy first minister in protest at the DUP's handling of the RHI scandal.
- Outgoing First Minister Arlene Foster denounces Sinn Fein's actions as "political, not principled".
10 January 2017
- The situation made an assembly election look "highly likely", says Secretary of State James Brokenshire, calling talks with all parties to find a resolution to the crisis at Stormont.
11 January 2017
- Sinn Féin says it will not enter negotiations ahead of new assembly elections.
- Prime Minister Theresa May says the government is putting in "every effort" to ensure a solution is reached, adding that Northern Ireland's voice would continue to be heard in Brexit negotiations.
13 January 2017
- RHI inspectors say they have suspended payments at more than half the boilers they have audited. OFGEM said of the 63 inspected, payments were suspended at 33. Five have since had payments reinstated after investigations.
16 January 2017
- An election is called after Sinn Fein refuse to nominate a deputy first minister to succeed Martin McGuinness.
19 January 2017
- A former adviser to Arlene Foster resigns after claims he exerted influence over the flawed energy scheme.
21 January 2017
- DUP MLA Jim Wells reveals that four members of his family installed wood pellet boilers under the RHI scheme.
23 January 2017
- MLAs pass regulations to cut the cost of the RHI scheme by lowering the tariff paid to claimants. The regulations are expected to save £30m in the 2017/18 budget - and will apply for 12 months.
24 January 2017