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Summary

  1. Renewable Heat Incentive Inquiry examining botched energy scheme
  2. DETI deputy permanent secretary Chris Stewart appears before inquiry panel
  3. Inquiry set up after public concern over scheme's huge projected overspend
  4. Retired Court of Appeal judge Sir Patrick Coghlin chairing inquiry at Stormont
  5. Public evidence sessions expected to last into autumn 2018

Live Reporting

By Iain McDowell and Robin Sheeran

All times stated are UK

That's all for today...

Stormont's Parliament Buildings
AFP

An extended afternoon session comes to a close, ending what's been a captivating couple of days with Mr Stewart in the witness chair.

Tomorrow is the inquiry's last day before it breaks for the summer and it promises to be an intriguing one as senior figures from the poultry giant Moy Park face questions about their firm's role in promoting the scheme to its suppliers.

Join us from 09:45 - until then, goodbye!

What happened today at the RHI Inquiry?

BBC News NI

Arlene Foster
PA

The inquiry has been told that there was an attempt to "protect" Arlene Foster during the closure of the RHI scheme, it emerged.

It was revealed by senior civil servant Chris Stewart that a former DUP adviser has made a reference in his witness statement to protecting the former first minister from blame.

Mr Stewart also said there was a "desire" in the DUP to make it appear that former enterprise minister Jonathan Bell had sole responsibility for what was an unpopular decision to shut down the scheme in 2016.

'Stakeholder pressure pushed closure back two weeks'

The closure of the RHI scheme faced a final day of two weeks, leaving it open for applications until 29 February 2016.

Mr Stewart says the decision to push back the closure was "an understandable political response to lobbying from stakeholders".

Chickens
Getty Images

But he admits that the decision was taken without any reference to the extra cost that would be incurred by the delay.

He became aware in February 2015 of communication from the poultry giant Moy Park to its suppliers that advised them to act quickly to get applications in for the scheme before it shut, which left him "surprised and dismayed".

'Being labelled a whistleblower could cause problems'

Mr Stewart objects to Mr Bell's characterisation of him during his interview with the BBC's Stephen Nolan in December 2015 as someone who went to the minister as a "whistleblower", describing it as "simply wrong".

He explains that senior civil servants in Northern Ireland can find themselves working for ministers from parties with widely differing views as there is a permanent coalition.

The RHI Inquiry
RHI Inquiry

"You can only do that if you have the trust and confidence of all ministers and all parties," he says.

If he was viewed as a whistleblower it would make it very difficult for him in the future "to enjoy the trust and confidence of any political party, not just the DUP".

'Tempers rose quickly after accusation of lying'

Mr Bell gave an "obvious angry reaction" when Mr Stewart later told him that it was he who had removed the reference to Arlene Foster from the submission about the closure of the RHI scheme.

It then became "instantly clear" that the minister had not made the request for the change to be made, says the witness, and his anger was "fully justified".

Burning wood pellets
BBC

Shortly afterwards, Mr Cairns joined the meeting and when he was challenged by Mr Bell about the change he suggested that Mr Stewart had lied to the minister, according to Mr Stewart's account.

"Tempers rose quickly," says the witness and Mr Cairns withdrew that claim shortly afterwards.

'Desire in DUP to make pin RHI blame on Bell'

There was a "desire" in the DUP to make it appear that Jonathan Bell had been solely responsible for the decision to close the RHI scheme without public consultation, says Mr Stewart.

He says there's a reference in Mr Cairns' witness statement to "protecting " Arlene Foster that suggests there was a "strategy emerging" to protect the first minister from the fallout.

He agrees with the inquiry barrister's suggestion that closing the scheme would be a "politically unpopular decision" and therefore there was an attempt for "full responsibility" for it to be attributed to Mr Bell.

Chris Stewart
RHI Inquiry

Mr Stewart says he didn't know at the time that the attempt to remove references to other ministers in the DETI submission was "against [Mr Bell's] wishes".

The inquiry chair Sir Patrick Coghlin tells him that Mr Cairns was therefore "representing something that was false" when he had requested that the changes were made to the document.

'Impossible to deny that contact had taken place'

In a BBC interview in December 2016, Jonathan Bell claimed that DUP advisers tried to "cleanse the record" by removing references to Arlene Foster from a paper about the RHI scheme.

That paper was a submission from the start of February 2015 about the decision to close the scheme without a public consultation.

The original document stated that the decision had been reached after the minister had discussions with the first minister and the finance minister.

A document marked: Strictly confidential
Getty Images

The adviser Tim Cairns asked Mr Stewart to remove the references to other ministers, saying that Mr Bell had "made the decision... and no advice from other ministers or departments played a part in that".

Mr Stewart says that was "factually incorrect and rather strange" because he knew otherwise: "These contacts had taken place - it simply wasn't possible to deny that they had."

The reference to the first minister was removed on the basis that it was Mrs Foster's advisers who had been consulted, not the minister herself, but the one about the finance minister remained in the document.

'Adviser asked for bypass of entire legislative process'

A microphone
BBC

Mr Bell's adviser Tim Cairns asked civil servants to request that the Northern Ireland Assembly committee process be "bypassed" in order to get the RHI scheme as quickly as possible.

Mr Stewart says it was a "bizarre" request, one that was intended to "bypass their entire legislative process".

'Tide had turned against on public consultation'

Consensus emerged between the DETI minister Jonathan Bell and finance minister Mervyn Storey that the RHI scheme should be closed without a public consultation, according to Mr Stewart.

He felt that a consultation was necessary to avoid the risk of legal challenge to the decision but "the tide had turned against us at that point".

Jonathan Bell
Pacemaker

Matters were "moving so quickly" that civil servants were trying to "catch up and create some sort of record of what had happened".

"It felt very uncomfortable, it felt very unusual," he adds and while he wasn't concerned that it was improper it was certainly "unorthodox".

'Poultry industry removed from executive paper'

A draft DETI paper on the RHI scheme that was to go to the Northern Ireland Executive was passed to the finance department for comment.

The paper came back with some suggested amendments - the finance department wanted to remove a section referring to "the poultry industry's use of broiler houses".

Mr Stewart objected to the removal of the text as it was factually accurate but the section was taken out of the final version that went to the executive.

Chickens
Getty Images

The DUP adviser Dr Andrew Crawford was working with the finance minister Mervyn Storey at that point.

Mr Stewart's view is that the suggestion for removal came from Dr Crawford and was because he "would have a better understanding of the agriculture industry than I do felt that it was actually factually incorrect".

That, he adds, is pure speculation on his part.

'Sinn Féin more keen to act quickly than DUP'

DUP and Sinn Féin ministerial advisers met at short notice at Stormont Castle to discuss what should be done about the closure of the RHI scheme.

Mr Stewart was also there and he remembers"there was quite a considerable measure of agreement" between the parties to get it shut it down without a public consultation.

A boardroom
Getty Images

He says that "Sinn Féin were even more keen on moving quickly than the DUP".

But he adds that the DUP advisers felt that civil servants were being "too cautious" and needed to "move more quickly" to stem the spend on the scheme.

'Where did RHI responsibility lie?'

Dr McCormick wrote to Mr Stewart advising him that the RHI crisis was now a matter for the then first minister Arlene Foster - she'd taken the role on just a couple of weeks earlier - and the head of the Northern Ireland Civil Service, Dr Malcolm McKibbin (below).

Dr McKibbin, who'd been copied into the McCormick email, wrote back saying the first minister "has made it quite clear" that it was DETI's responsibility of DETI to "mitigate costs and to urgently cease accruing further liabilities".

Sir Malcolm McKibbin
BBC

Mr Stewart says he was "very surprised by it and I didn't understand it".

Asked how the confusion came to be about which department was responsible for handling it, he says: "I really can't provide an illuminating answer on that."

'Unthinkable for RHI closure to be delayed further'

The crisis was escalated through Stormont's finance department and the first and deputy first ministers' office as well as to the head of the Northern Ireland Civil Service.

The then DETI permanent secretary Dr Andrew McCormick (below) expressed his frustration with the delay in getting the RHI scheme's closure approved to his then finance department equivalent David Sterling.

Dr Andrew McCormick
BBC

"The issue is where it is. There's nothing more Chris or I can do to shift it - unthinkable this is delayed any further," he wrote in an email.

Mr Stewart describes that as "fairly direct language" and says it made the point that even senior civil servants "had limited or any ability to influence" the situation.

'I think minster Bell was confused'

It's not unusual for policy decisions to be considered by political party advisers, says Mr Stewart.

"What is unusual is for that to happen after a minister has purportedly cleared the [submission]."

The RHI Inquiry
RHI Inquiry

He didn't know whether the minister had been persuaded to rescind his decision or if it had been done for him.

Based on emails he has seen, he says: "I think the minister was confused as to what the position was as well."

'Rescinding of minister's approval wasn't done by Bell'

Official approval was given by Jonathan Bell to close the RHI scheme on 22 January 2016 but it was rescinded about 20 minutes later.

Asked who was responsible for that, Mr Stewart says it was "clearly not" rescinded by the minister but he isn't pinning it on anyone.

A document being stamped as 'approved'
Getty Images

He says he has never before or since "remember a submission being uncleared" and it caused "puzzlement" but he feels that DETI's energy boss John Mills was "more suspicious" and viewed it as a "delaying tactic".

Mr Mills told the inquiry last week that he thought there were "very disturbing reasons for it", one of those being that it would "allow people to make applications before closure".

The minister's adviser Tim Cairns said the submission was in the hands of "DUP party officers" - Mr Stewart took that to mean that DUP ministerial special advisers, referred to as spads, had it.

'Rush to get RHI closure passed before election'

DETI needed to act quickly to get the scheme closed and a submission was sent to the minister Jonathan Bell on 19 January 2016, advising that a public consultation on the matter should be approved for issue the next day.

voters at a polling station
Pacemaker

The department had to get the consultation out quickly in order to allow the legislation to pass before the Northern Ireland Assembly rose for an election in March that year.

The submission was marked "immediate" - Mr Stewart explains that that was necessary in order to get it put straight on to the minister's desk as "too many things are marked 'urgent'".

Time for lunch...

Time to grab a snack and catch some rays - the inquiry returns at 14:00 for the afternoon session.

'Minister recognised RHI was a catastrophe'

On New Year's Eve 2015, the then enterprise minister Jonathan Bell (below) was told in a ministerial submission that he had "no choice but to close" the RHI scheme as soon as possible.

Mr Stewart says it was "decision time" for the minister and Mr Bell agreed to the closure at a meeting on 11 January 2016.

In "contrast" to the cost controls saga of the previous summer, he says Mr Bell's adviser Tim Cairns offered no resistance but he adds: "It would've been a brave man or woman who would've opposed the rationale that we needed to close."

Jonathan Bell
BBC

Asked what the reaction was from Mr Bell and his adviser, Mr Stewart says he doesn't remember any anger or the apportioning of blame at that stage.

"I think we were all a bit shell-shocked at the situation we'd found ourselves in," he says.

"I think there was a recognition on the ministers part and on Timothy's part as well that this was a very, very serious situation - it was a catastrophe."

'Christmas was wrecked as RHI became full-blown crisis'

DETI officials held out hope for much of December 2015 that the Treasury would agree to take at least some of the hit of the massive overspend on the RHI scheme.

But on 21 December the Treasury "put absolutely beyond doubt" that it wouldn't be picking up the bill, says Mr Stewart - yesterday he described that as a "day of complete dismay".

Santa under a Christmas tree
Getty Images

After that point, the scheme became a "full-blown crisis" as the race was on to get the scheme closed - he says he then took a much more hands-on role in dealing with it.

Mr Scoffield says he has "no doubt" that some people would've had their "Christmases wrecked that year by virtue of what had happened and what needed to be done".

'Brave step to call for need to close RHI'

Mr Stewart says he regrets not heeding a warning from a civil servant that there was "no choice" but to shut down the RHI scheme as applications were flooding in.

Stuart Wightman, who was managing the scheme, emailed Mr Stewart midway through November 2015, telling him that there'd been 800 applications in the previous six weeks.

A hand pushing an emergency stop button
Getty Images

That was a "brave and significant step", says Mr Stewart.

But he didn't immediately act on it and it wasn't until more than three weeks later that he "reached the view that closure or suspension was required".

'Special adviser raised concerns about RHI fraud'

Tim Cairns, the former DUP adviser, has told the inquiry that he raised with concerns with Mr Stewart about potential fraud in the scheme - issues that had been brought to his notice by fellow DUP adviser Dr Andrew Crawford.

Mr Cairns said he raised the matter with the senior DETI civil servant at least 10 times.

But Mr Stewart says it was more like twice and that he was given no source for the concerns or details about what was being alleged - there was a "a general vagueness" about the reports.

The RHI Inquiry
RHI Inquiry

Mr Stewart had his officials check with the scheme's administrator Ofgem, which replied that there had been only four incidences of problems - all of them minor matters.

He's also highly critical of Ofgem's method of inspections, saying they were "devoid of utility" because claimants were given prior warning that they would receive a visit from auditors.

Later investigations of RHI scheme installations, carried out by by the professional services firm PwC, found that there was concern or suspected fraud in more than 50% of boilers that were examined.

'In industry's interests to give us truthful information'

The early closure of the RHI scheme was the "worst possible outcome" for DETI and for industry, says Mr Stewart.

It was shut down in February 2016 because the cost had spiralled out of control after applicants clambered to sign up, having been encouraged to do so by some within industry.

Sterling banknotes
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Mr Stewart wonders "whether on mature reflection" industry figures "thought sufficiently not only about our interests but their own" in relation to the scheme's sustainability.

It was industry's interests to "give us good, accurate, truthful, valid information" about their plans to "legitimately take advantage of the scheme", allowing the initiative to be a success and keep on running.

'Was DETI played by industry figures?'

Civil servants clearly "had insufficient understanding of the market conditions" regarding the installation of renewable heating systems, including in areas such as poultry, Mr Stewart admits in his witness statement.

They also misunderstood the industry's ability to react quickly to market conditions, one of the reasons that caused the major spike in application to the RHI scheme in autumn 2015.

A biomass boiler
BBC

DETI officials tried to rectify some of their lack of understanding by consulting with industry figures.

Mr Scoffield asks if the department was "played" by the industry.

"I don't think we were best served by the responses that we received and I don't think industry was best served by the answers that they gave," Mr Stewart says.

'Foster request for delay unusual and unwelcome'

Delaying the addition of cost controls to the RHI scheme by just a week would've added at least £2.6m a year over to the cost of the initiative over its 20-year lifetime.

That query made for a constituent on behalf of Mrs Foster to hold off on the assembly debate on adding the cost controls was "unusual and certainly unwelcome", says Mr Stewart.

Wood pellets
PA

He tells the inquiry that civil servants "felt the need to dispatch it fairly quickly".

Mrs Foster's evidence is that she accepted their answer and the intervention had no delaying effect and Mr Stewart agrees with her view.

'Not enough Fermanagh businesses had chance to apply for RHI'

A DUP adviser asked on behalf of Arlene Foster (below) whether the Northern Ireland Assembly debate on passing the cost controls for the RHI scheme could be delayed by a week or two, the inquiry hears.

Tim Cairns posed the question after Mrs Foster had received a query from a constituent in her Fermanagh and South Tyrone constituency.

It's been claimed by senior civil servant Dr Andrew McCormick that Mr Cairns referred to a concern that "not enough businesses in Fermanagh had been able to apply" before the cost curbs would be put in place.

Arlene Foster
BBC

But he takes issue with that and denies that such wording was used.

Mr Stewart says he remembers his colleague discussing that conversation and referring to that wording - he says it was a "rather unusual phrase".

They "both took that as a not-very-subtle indication" that the query had come from Mrs Foster.

'Delay to scheme changes had big cost implications'

The RHI scheme's cost controls were due to come into effect at the start of November 2015 but there was a two-week delay to that, which had "very significant implications" for the initiative' overall cost.

In that time, applicants piled into the scheme to qualify for the most lucrative subsidies, contributing massively to the vast projected overspend.

Pound coins
Getty Images

The delay was caused by what Mr Stewart describes as "unforseen difficulties" in getting some aspects of the legislation - parts not related to cost controls - pushed through.

Mr Stewart says he "should've been more curious about" the the process and acknowledges that the legislation should've been narrowed in order to make it easier and quicker to pass.

Senior civil servants should've been "more sensitive" enough to the "extreme risk" of a delay in getting the cost controls into effect, he says, and should've "prioritised this more than was the case".

'Never encountered resistance like it in my career'

The degree of "resistance" to DETI's attempts to add cost controls to the RHI scheme was "surprising", Mr Stewart says in his witness statement.

He adds that he's never encountered a "similar phenomenon at any time during my career" as a civil servant under ministers from several political parties.

Burning wood pellets
BBC

Expanding on this, he says he could "see no good reason" for the plan to be opposed and he agrees with the suggestion that there were delaying tactics on the part of DUP advisers.

"It seemed to me that we were not getting rational or reasoned counter-argument but resistance," he adds.

'Lack of minutes a breach of civil service guidance'

A meeting was held in late August 2015 in which the DETI minister approved the addition of cost controls to the RHI scheme with the added stipulation of a one-month delay in their introduction.

No record was taken of the meeting - another example of the absence of minutes that has dogged the work of the inquiry.

The RHI Inquiry
RHI Inquiry

Mr Stewart was on annual leave so he's limited in what he can say about the meeting but he's asked whether the lack of notes was a breach of civil service procedure.

"My understanding is that, yes, there was guidance in place that we were not following," he replies.

'Overruling civil servants' warning is line you shouldn't cross'

Mr Stewart told the DETI minister's adviser that if they wanted to introduce the proposal to increase the usage threshold for RHI scheme claimants it would require a formal direction from Mr Bell to overrule civil servants' objections to the plan on value-for-money terms.

He tells the inquiry that he tried to give Mr Cairns a sense that it was "a line you shouldn't cross - this is very serious".

Chris Stewart
RHI Inquiry

And he says that the minister and adviser would've needed an "overwhelming cause or argument" to go against the advise of senior civil servants.

He believed that was enough for Mr Cairns to take back to those within the DUP who were behind the suggestion to say that it was "something that officials thought was unacceptable".

'Heating empty sheds couldn't be defended'

In dismissing the proposal for increasing the usage threshold for RHI scheme claimants, Mr Mills (below0 pointed out that 3,000 hours a year would be more that was required annually to heat a poultry shed.

Many of the claimants on the RHI scheme are poultry farmers.

Mr Mills said that "suggestions of heating empty poultry sheds cannot be defended in value-for-money terms".

John Mills
RHI Inquiry

Mr Stewart says he doesn't believe that DETI's energy boss was suggesting that was actually taking place but was giving a hypothetical example.

He says Mr Mills' advice was "a basis to go back quickly" to the minister's adviser to "say [the 3,000 hours proposal] is not feasible".

The witness says he now realises it also represents "a clear warning" that if that is an issue with the 3,000 hour figure "then its more of an issue with no tiering limit".

'Energy boss robustly rejected DUP's scheme change'

At the end of July 2015, Mr Cairns put forward a further proposed change to the planned amendments to the RHI scheme.

It was one that originated from his fellow DUP adviser Dr Crawford - the plan was to increase the threshold of hours that a claimant could run their biomass boiler for before RHI scheme payments would be reduced.

A biomass boiler
BBC

DETI's plan was to mirror the threshold in the similar RHI scheme in Great Britain of 13,14 hours but Dr Crawford wanted that to be more-than-doubled to 3,000.

The inquiry barrister says it was dismissed "very quickly and robustly" by DETI's energy boss John Mills, who said it had no merit in value-for-money terms.

Mr Mills told the inquiry last week that he wanted to "kill off" the proposal and viewed it as part of a tactical plan to stall the cost controls.

'Resistance to cost controls came from DUP'

Civil servants' attempts to curb the cost of the RHI scheme were met by "resistance" by some DUP figures, says Mr Stewart.

The DETI minister's adviser Mr Cairns suggested to Mr Stewart that the addition of cost controls should be delayed as their introduction in October could lead to a spike in applications to the scheme.

But Mr Stewart countered that there was already an increase in demand and that a well-informed industry would keep demand high.

Boiler
BBC

He tells the panel his view at the time was that delay would not make matters better at best a "spike might turn into a plateau".

The witness says he thinks the proposal to delay the changes was based on a DUP view, not from the adviser himself or the minister - he believes Mr Cairns saw the need for cost controls but needed something to sell to the party.

He attributed the delay to the party viewing the RHI scheme as good for industry, he adds, and you "don't hobble a good scheme any more than is necessary".

'Proposed scheme changes were coming from DUP, not minister'

Mr Stewart says he assumed that the submission regarding the changes to the RHI scheme did not actually reach the DETI minister until the end of August 2015.

Instead, he believed it was only ever in the hands of his Democratic Unionist Party (DUP) ministerial adviser up to that point.

He says he took that view because the adviser Timothy Cairns returned to civil servants with suggested amendment that "were at a level of detail I wouldn't have expected... from a minister".

A biomass boiler
BBC

And he adds that Mr Cairns didn't say that he'd discussed the submission with Mr Bell.

"I got the impression that the suggestions that were coming back were... as a result of party considerations."

Evidence the inquiry has seen shows that Mr Cairns had been discussing the changes with another DUP adviser Dr Andrew Crawford, who had put forward possible changes to it.

'Submission to minister was inaccurate'

Inquiry barrister David Scoffield QC (below) picks up the questioning at the point where he finished yesterday, with a submisson that was sent to the enterprise minister Jonathan Bell on 8 July 2015 - it's a key document in the story of the RHI debacle.

In it, Mr Bell was informed about the emerging problems with the scheme and how DETI officials proposed to deal with them.

David Scoffield
RHI Inquiry

An early version, which clearly stated the projected expenditure in 2015-16 was £23m - twice the available budget - was amended to remove the cost controls warning.

A paragraph which suggested that a funding shortfall might have to be paid from other DETI spending commitments was also completely removed.

Mr Stewart says the submission was "inaccurate in its description of funding and in particular its description of the risks" associated with that.

Witness Chris Stewart returns to give evidence

It's a second day in the witness chair for Chris Stewart, the deputy permanent secretary at the Department for the Economy.

The department was formerly the Department of Enterprise, Trade and Investment (DETI) and it set up and ran the RHI scheme.

Chris Stewart
RHI Inquiry

Mr Stewart joined DETI in August 2014 and his deep involvement with the RHI scheme appears to have started in May 2015, when he began helping to manage it as it started to run out of control.

You can find his two witness statements on the inquiry's website here and here.

His evidence yesterday was eye-catching at times and he'll be answering many more questions from the inquiry's senior counsel David Scoffield QC today.

What happened yesterday at the RHI Inquiry?

BBC News NI

A top civil servant told the inquiry that he felt officials were treated as the "opposition" by DUP advisers as they tried to curb the rising cost of the flawed RHI scheme in 2015.

Chris Stewart said he felt the civil servants, advisers and their ministers were not "on the same team" as they struggled to rein in spending.

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Mr Stewart, one of the top tier of management in Stormont's economy department, acknowledged that it was a big statement to make.

And he said had there been greater trust between officials, advisers and the minister they could have thrashed out an approach that might have been much more effective.

What is the RHI Inquiry?

BBC News NI

An independent inquiry into the RHI scandal was established in January last year by the then finance minister Máirtín Ó Muilleoir.

He ordered it in the wake of the huge public concern and what was then a developing political crisis surrounding the scheme.

The RHI Inquiry began in November and Sir Patrick Coghlin (below), a retired Court of Appeal judge, is its chair and has been given full control over how it will operate.

Sir Patrick Coghlin
Pacemaker

It will look at:

  • the design and introduction of the RHI scheme
  • the scheme's initial operation, administration, promotion and supervision
  • the introduction of revised subsidies and a usage cap for new scheme claimants in 2015
  • the scheme's closure

For more information on the RHI Inquiry, you can read our handy Q&A.

RHI scheme - the fallout

When the scale of the overspend emerged, public and political concern rocketed.

As the minister in charge of the Stormont department that set up the RHI scheme, the Democratic Unionist Party (DUP) leader Arlene Foster faced calls to resign from her role as Northern Ireland's first minister in December 2016.

Martin McGuinness and Arlene Foster
Pacemaker

She resisted, and Sinn Féin's Martin McGuinness then quit as deputy first minister in protest at the DUP's handling of what had by then become a full-blown political crisis.

That move brought about the collapse of the Northern Ireland Executive. Now, a year-and-a-half on from that, Northern Ireland remains without a devolved administration.

You can find much more detail on the RHI scheme in our need-to-know guide.

RHI scheme - the flaws

The budget of the RHI scheme ran out of control because of critical flaws in the way it was set up.

Claimants could effectively earn more money the more fuel they burned because the subsidies on offer for renewable fuels were far greater than the cost of the fuels themselves.

Burning £20 notes
BBC

The most recent estimate for the overspend was set at £700m, if permanent cost controls aren't introduced.

The massive overspend bill will have to be picked up by the Northern Ireland taxpayer.

RHI scheme - what was it?

The Renewable Heat Incentive scheme - or RHI for short - came to the fore of the Northern Ireland public's knowledge in late-2016... and the fallout from the scandal attached to it is still being felt in the region's politics today.

A biomass boiler
Getty Images

The scheme 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.