Timeline: How Renewable Heat Incentive unfolded
November 2012 - Arlene Foster, then Enterprise Minister, announces the Renewable Heat Incentive scheme for businesses.
October 2013 - A whistleblower emails Mrs Foster to express concerns over the scheme.
Autumn 2013 - The woman is referred by Mrs Foster to officials from her Department of Enterprise, Trade and Investment, and she urges them to address the problems.
May 2014 - The whistleblower emails again, after the civil servants appear to do nothing. She explicitly outlines how the scheme was being abused, was paying out exorbitant sums of money, and could not be ignored any longer.
December 2014 - The scheme is extended to domestic customers by Mrs Foster.
November 2015 - With the realisation the funding available for applicants is uncapped, Stormont tightens the rules.
But a massive late surge of 900 applications is received before changes can be made.
January 2016 - Another whistleblower civil servant tells the Executive the scheme is being abused.
February 6 - New Enterprise Minister Jonathan Bell (above) makes a shock announcement that the RHI scheme to be scrapped.
February 9 - Michael Doran of Action Renewables warns it will force renewables from "boom to bust."
June - Auditors begin investigating concerns.
July 5 - A damning Audit Office report states a farmer will make £1m of government money just for heating an empty shed. It reveals that more than £1 billion of public money will be paid to Northern Ireland-based businesses by 2036 after they installed new appliances under the RHI scheme.
October - Stormont's Public Accounts Committee (PAC) call the mishandling of the RHI scheme "one of the biggest scandals" since devolution. SDLP Assembly member Daniel McCrossan tells officials from government utility regulator OFGEM, which administered the scheme: "It was very clear the department was asleep at the wheel but I am horrified that you too were asleep at the wheel in relation to this."
November - The Public Accounts Committee is told that a £405m hole will have to be plugged over the 20-year lifetime of the RHI.
Dr Andrew McCormick (above), permanent secretary for the Economy Department, says he can't think of any government scheme being worse value for money.
12 December: First Minister Arlene Foster says she won't quit over the fiasco following allegations that she did not act appropriately when concerns were first raised about the scheme. It also emerges the brother of a DUP special advisor and a Ferrari showroom have benefited from the error-ridden scheme.
13 December: UUP leader Mike Nesbitt claims to have uncovered the "smoking gun" of Arlene Foster's involvement in the decision-making process in connection with the flawed RHI scheme.
14 December: The SDLP says it will table a motion of no confidence to exclude Arlene Foster as First Minister. Sinn Fein says it won't back the motion. Meanwhile the UUP says the UK Government can no longer ignore the "national scandal".
The DUP's Nigel Dodds hits out at a "scurrilous attempt" to blame Arlene Foster for the botched energy scheme. The party releases what it says is a copy of the 2013 email sent from the whistleblower to Mrs Foster, saying that it raised no specific concerns about RHI.
15 December: Arlene Foster says she has nothing to hide from a BBC interview with former DUP minister Jonathan Bell, who vowed to tell the truth about the scandal, adding the revelations will end his political career.
Jonathan Bell claims DUP advisers attempted to delay the closure of the scheme in its original and generous format. He also said attempts were made to remove references to the Finance Department and Arlene Foster in records. The claims were denied.
16 December: Deputy first Minister Martin McGuinness calls for the DUP leader to stand aside from her role as First Minister while a full investigation is carried out into the scheme. The DUP rejects the call.
19 December: Arlene Foster faced a motion of no confidence as the devolved assembly was recalled for a special sitting to discuss the growing political crisis in the run-up to Christmas. The First Minister apologised for failing to put in place cost controls, but defended her role. The motion of no confidence failed on a cross-community vote.