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  1. Renewable Heat Incentive Inquiry examining botched energy scheme
  2. Former DETI official Peter Hutchinson returns for another day's questioning
  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 until well into 2018

Live Reporting

By Robin Sheeran and Iain McDowell

All times stated are UK

That's all for now...

Another of the most hands-on civil servants in the RHI scheme - Mr Hutchinson's former boss Fiona Hepper - will return to the hotseat tomorrow.

Parliament Buildings

Join us tomorrow morning from 09:45 for more live coverage of the RHI Inquiry from at Stormont's Parliament Buildings.

Have a great evening...

What happened today at the RHI Inquiry?

BBC News Northern Ireland

Civil servants got a "clear warning" of a key problem in a botched green energy scheme, the inquiry was told.

Burning £20 notes

It heard that the issue of multiple smaller boilers being installed to maximise subsidy receipts was raised with officials at DETI.

The warning was given by a group representing fuel suppliers in 2013, two years before the scheme imploded.

'Your work on RHI scheme was incredible'

Civil servants and the ministers directing them need to be more realistic about what is possible with the time and resources at their disposal, says Mr Hutchinson.

Ministers should also be involved in policy-making within their departments, he adds.

Those, he says, are two of "undoubtedly a lot of lessons to be learned" from the RHI scheme debacle.

Peter Hutchinson
RHI Inquiry

Speaking on behalf of the inquiry panel, Dame Una O'Brien acknowledges "how phenomenally hard" Mr Hutchinson worked and his "prodigious output" on the RHI scheme.

It's an emotional moment for Mr Hutchinson - he's spent the guts of a week in the witness chair under close scrutiny in full public view and his questioning is finally at an end.

'My handover more detailed than anything I've received'

Mr Lunny takes the inquiry back to the handover document Mr Hutchinson prepared for his successor working on the RHI scheme.

It doesn't mention monitoring, the CEPA projection that the 10% renewable heat target would not be met, or cost controls in anything other than the briefest terms.

A man handing a folder to a woman
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"I've given them an outline of work for a number of months," Mr Hutchinson says in his defence.

"When I look at it I think it's quite detailed. It's more than I've ever received," he adds.

He returned to DETI for a meeting some months later with his successors to discuss the scheme, but their questions focused on the domestic initiative, and he can't recall if he asked how the non-domestic one was working at that point.

'Two officials' departure wasn't the best idea'

Mr Hutchinson says he was surprised that both he and Ms McCutcheon were being released from DETI at about the same time.

Mr Lunny asks if the question was ever raised about whether it was "sensible or safe" for that to happen, given their combined knowledge and experience of the RHI scheme.

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The witness says he never raised it with Mr Mills, but Ms McCutcheon did, and he says: "I think she maybe suggested it wasn't the best idea."

Asked if he suggested there should've been a degree of continuity on the team working on the scheme due to some of the problems that needed attention, Mr Hutchinson says the "ramifications" of what could happen in his absence "weren't there" at the time.

"If I had seen what had happened after that yes, I'd say I wouldn't have left or maybe I wouldn't have joined in the first place."

'Staff departures left experience void on RHI'

Mr Hutchinson left DETI in May 2014, and a move to another Stormont department had been on his mind for several months.

He was given the go-ahead by Mr MIlls to take up a post at the Office of the First Minister and Deputy First Minister (OFMDFM).

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His move was one solely for the development of his career and it was not a case that he was "trying to jump ship", he explains.

Ms McCutcheon - the only other person working directly on the RHI scheme - had also been granted a career break at the same time, meaning that there was what Mr Lunny describes as an "experience void" on the project at DETI.

'Was new energy boss aware of need for review?'

DETI's core team working on the RHI scheme from the outset - Mr Hutchinson, Joanne McCutcheon and Fiona Hepper - all left the department between late-2013 and mid-2014.

Mr Hutchinson is asked whether Mr Mills - Ms Hepper's successor - was then the only energy division official who was aware of the need for a review of the entire scheme in 2014.

A biomass boiler

The witness says that was indeed the case - for anyone else to have found that out they would've need to have read a number of documents.

"You're confident that Mr Mills did know about it from the discussions you had had with him before you left?" asks Mr Lunny.

Mr Hutchinson says he only had one discussion with Mr Mills on the subject, and he thinks it would have been raised.

'Review never happened due to other pressures'

A crucial planned review of the RHI scheme in 2014 did not start because the staff working on it were "heavily involved in other things", says Mr Hutchinson.

A magnifying glass
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It was discussed "infrequently" but never happened because "other work pressures took priority" and there may have been "no direction to start it".

He is unaware of any arrangements in place for a review when he was leaving the department in late-spring 2014.

'No arrangements in place for RHI review'

A commitment had been made several times, as far back as 2011, to a review of the non-domestic RHI scheme, starting in January 2014.

Indeed, the Department of Finance and Personnel's letter of approval for the scheme made it clear that it was a requirement that a series of reviews be put in place.

Peter Hutchinson
RHI Inquiry

Mr Hutchinson is asked what arrangements were put in place for the review during his time at DETI.

"I don't think there were any formal arrangements - you know it's not on a database," he replies.

It was "more a case of knowledge of the need for it", he adds.

'Not a shred of evidence to support claim'

Inquiry chair Sir Patrick Coghlin says he has "not seen a shred of evidence" that suggests Mr Mills's view that the DETI minister decided to prioritise opening the domestic RHI scheme over adding cost controls to the non-domestic initiative.

Mr Lunny asks if Mr Hutchinson is aware of any document that sets out why the cost controls were "put off" in favour getting the domestic scheme up and running.

A biomass boiler

"No," says the witness.

Mr Mills will have to be asked why he made that statement, says Mr Lunny.

'Did Foster decide to push to with domestic scheme?'

Mr Lunny jumps forward to a DETI casework committee minute from October 2015 that he says may cast some light on why the domestic RHI scheme was prioritised over cost controls.

Mr Mills was present and was asked about the trigger points for cost controls that were not implemented in 2013 and whether they should have been included.

The RHI Inquiry
RHI Inquiry

He said "it was a ministerial decision to look at the domestic scheme rather than pushing through the trigger points on non-domestic".

Mr Lunny asks Mr Hutchinson if he knows who made the decision to "park" the other elements of the scheme's development in favour of the domestic initiative: "Was it the DETI officials or was it the minister?"

Mr Hutchinson says: "Certainly it wasn't the minister, you would see that in the submission."

'Timescale for scheme changes overly optimistic'

There was pressure on DETI from stakeholders to get the domestic RHI scheme open because the department had fallen behind the stage the similar initiative in Great Britain was at, says Mr Hutchinson.

The domestic scheme "might have been a priority" for DETI, he adds, but that was not at the cost of "forget about everything else".

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"It was definitely seen as more deliverable than [changing] the non-domestic tariff at that stage, yes."

In his written statement to the inquiry, John Mills, then the head of DETI's energy division, says there was an "underestimation" of how long it would take to get the domestic scheme up and running and therefore "overly optimistic assessments of when" the changes to the non-domestic scheme could be made.

'Cost controls not mentioned in submission to Foster'

In its development of the RHI scheme, DETI had planned to expand the non-domestic initiative and add cost controls to it at the same time as introducing a similar scheme for domestic users.

The department's energy team made a submission to the minister, Mrs Foster, (below) in November 2013 that suggested that it could push ahead with getting the domestic scheme opened the next spring.

Arlene Foster

Plans for the non-domestic initiative could be left for later, it was suggested.

There was also no mention of cost controls for the non-domestic scheme in the submission to Mrs Foster.

Mr Lunny asks if that is evidence of a shift in DETI's priority to the domestic project, but Mr Hutcinson disagrees, explaining that there were "complexities" with the non-domestic scheme that meant it was being held up.

'I crafted temporary cost control measure'

DETI's consultation on the development of the RHI scheme contained a novel proposal for a temporary cost control.

This would have seen a five-trigger mechanism ultimately resulting in the closure of both the domestic and non-domestic schemes, which Mr Lunny describes as "a less-demanding cost control" than full-blown digression.

Dame Una O'Brien
RHI Inquiry

Inquiry panel member Dame Una O'Brien intervenes to ask Mr Hutchinson: "Who crafted this?"

"I have to put my hand up again," he replies.

'More could've been done over missed target'

Inquiry panel member Dr Keith MacLean is surprised that there was "no real reaction" at DETI when CEPA predicted that the 10% renewable heat production target would not be met.

Dr Keith MacLean
RHI Inquiry

"Did the hands not go up?" he asks. "The thing is so fundamental and justified the money being spent."

"I don't recall anything specific," Mr Hutchinson says, adding that he agrees that "more could have been done".

'Report found key heat target would be missed'

As ad been the case before the RHI scheme was first opened in late-2012, CEPA was commissioned by DETI to carry out an economic appraisal on the planned changes to the initiative.

In June 2013, it delivered a report that projected that the scheme would not help Northern Ireland to achieve the target of producing 10% of its heat through by renewable sources by 2020.

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Mr Hutchinson says DETI was "always aware the 10% target would be difficult" to meet.

A submission was sent to the DETI minister that same month about the development of the scheme, but it didn't mention that the key 10% target was now off the cards.

Mr Hutchinson has no explanation as to why that information was missing.

'Lawyers paid to ensure nothing was missed'

DETI commissioned the legal firm Arthur Cox in early-2013 to report on changes that DECC had made to its RHI scheme regarding cost controls.

The inquiry has heard evidence from Alan Bissett, who was a partner a Arthur Cox when it was asked to carry out the work.

Lawyers looking at documents
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He said the request seemed "odd" because he felt DETI would have been "in a better position" to find out that information than his firm was.

Mr Lunny asks Mr Hutchinson why the work couldn't have been done in-house by DETI, instead of paying lawyers to do it.

The witness explains that the staff working on the RHI scheme didn't have the time to do it and asking Arthur Cox to scrutinise DECC's changes would ensure "nothing would be missed" because they "maybe had a better eye for it than we would've had".

'DETI was keeping eye on GB scheme developments'

Back after the lunchtime break, Mr Lunny says the inquiry will look at monitoring of the RHI scheme and cost controls this afternoon.

After problems with a domestic energy generation scheme, the Department for Energy and Climate Change (DECC) introduced temporary cost controls its RHI scheme in Grea Britain that would allow the initiative to be suspended in-year.

DECC logo

This was followed by the introduction in April 2013 of a measure - known as digression - that allowed the tariff to be lowered in response to increased demand.

Mr Hutchinson confirms that DETI was keeping a close eye on developments with the GB scheme.

'Could have told Foster about subsidy issue'

On his last day at DETI, Mr Hutchinson prepared an update for the Northern Ireland's Enterprise Committee on the RHI scheme.

It was sent to the department's minister Arlene Foster, its permanent secretary David Sterling, among others.

In it, he outlined that the majority of biomass boilers accredited through the scheme were collecting the most lucrative subsidy on offer, and he wrote that it "may be appropriate to review" the rate of that subsidy, given evidence that had emerged but there was no further detail as to why.

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The review never happened, though, and Mr Hutchinson is asked why the committee nor the minister was not told in more detail why a review should happen.

He says he felt the need for the review should first have been discussed by DETI's energy team, but accepts it would've been possible to tell Mrs Foster there was a "specific issue... and we're investigating further".

He believed it was an issue that "could be fixed quite easily, incorrectly so".

'Handover note was the only objective evidence'

Mr Hutchinson's handover note was intended for Ms McCay, but he believes he may have emailed a copy to Mr Mills, who by that stage had replaced Fiona Hepper as the head of DETI's energy division.

The inquiry has not uncovered any such email, says Mr Lunny.

Inquiry chair Sir Patrick Coghlin is concerned that the document, which includes the terms "immediate and urgent", should have gone to Mr Mills, and he is "anxious to know" if it did.

Sir Patrick Coghlin
RHI Inquiry

"In this case you knew Fiona had left, you knew (Joanne) McCutcheon had left and your handover note was perhaps the only objective evidence of what had gone before and what ought to come," adds the chair.

"It might have been discussed with him after I left, but I don't think I personally... I think I've talked to him about it," Mr Hutchinson says.

He says he flagged it up at a heads-of-branch meeting before he left DETI.

'Whistleblower's follow-up chimed with me more'

Further contact from the so-called whistleblower Mrs O'Hagan in May 2014 "chimed with me" more than the initial issues she had raised about the RHI scheme, says Mr Hutchinson.

She emailed him to reiterate the concerns she'd expressed at the meeting with DETI the previous October.

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In the email, she said "there is no incentive at all to be efficient" and the "heat in buildings is on all year round with windows open everywhere".

"When we had spoken you did not believe this, but please believe me, this is happening with almost everyone we approach," she added.

'Evidence you've shown me had rung alarm bells'

Mr Hutchinson says that some of the evidence the inquiry has shown to him yesterday and today would be "alarm bells" and would cause him to think to himself: "Why didn't you pick this up far sooner?"

Another of those is a Smart Eco Hub event near Newry in March 2014, which he attended and gave a talk at, along with installers of renewable heating systems.

£10 notes

He sat through a presentation by one installer - Conall McMullan of Alternative Heat - who outlined how the RHI scheme provided a "massive rate of return on the investment" and a "guarantee of a 20-year income".

The "major returns" made it a "safe bet", added Mr McMullan.

Mr Hutchinson says that was one "trigger" for him to look again at the payments on offer through the scheme and notice that there were issues to be addressed.

'Immediate action required on RHI tariffs'

Mr Hutchinson left DETI in May 2014, and in his handover note to his successor Davina McCay he listed a series of "immediate actions" required by the end of August that year.

They included a review of non-domestic biomass tariffs for installations under 100kW on the RHI scheme and the consideration of tiered tariffs to prevent excessive payments.

A man handing over a folder
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He explained that it had become apparent that payments were higher than those envisaged by consultants at Cambridge Economic Policy Associates, who had been engaged to draw up the scheme and calculated the tariffs.

The administrator Ofgem had advised that boilers were being used for much longer periods than expected and as a result the tariffs could become overgenerous.

Ms McCay was told that the issue should be considered "as a matter of urgency".

'CEPA looked at it and it's not happening'

Mr Lunny puts it to the witness that DETI's main reason for being sceptical that people might behave as Ms O'Hagan had suggested was that the officials may have thought: "CEPA have designed this tariff - we think their design is robust".

Donal Lunny
RHI Inquiry

Mr Hutchinson says that if someone had said to him in 2013: "'How do you stop people wasting heat?' I think my stock answer would always have been; 'CEPA looked at that and it's not happening.

"'It doesn't mean it won't happen in the future and we'll continue to look at it.'"

'Whistleblowers concerns not raised as clarly as made out'

When Mrs O'Hagan was described as a "whistleblower" in the media when the scandal of the RHI scheme emerged in December 2016, Mr Hutchinson says he was "confused".

In his written statement to the inquiry, he says he wouldn't have applied that label to her.

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"She was an interested stakeholder - very helpful, very interesting very informative," he tells the inquiry.

He adds that the concerns Mrs O'Hagan raised are "a lot more clear now" than there were at the time of her meeting with him and other DETI officials.

"I'm not sure there was that clarity at that point - not in my mind at least."

'Whistleblower not rejected over commercial interests'

Mrs O'Hagan became aware of the RHI scheme when she was trying to market her energy efficiency product in late-2012 and early-2013.

She noticed that her target market had no interest in her product because most were claiming from the scheme, and it appeared to her to disincentivise efficient use of heat.

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Inquiry panellist Dr Keith MacLean asks whether the DETI officials who met her felt she had a "vested commercial interest in what she was saying" and were therefore cautious in taking what she said at face value.

Mr Hutchinson says: "I don't think you would've said: 'We're not listening to you because you're selling a product,' but he adds that other issues at the time suggested to the contrary of what she was telling them.

Mrs O'Hagan was invited to submit her concerns as part of the public consultation on the scheme that was running at the time - she declined to do that and Mr Hutchinson acknowledges that he could have gone back to her to seek more information.

'I didn't tell whistleblower we didn't believe her'

A businesswoman tried to draw the then DETI minister Arlene Foster's attention to a major flaw in the RHI scheme in August 2013, and she was granted a meeting with Mr Hutchinson and other officials working directly on the initiative.

Janette O'Hagan (below), who's been described as a whistleblower, told them it was so lucrative she was surprised firms were not putting radiators on the outsides of their buildings.

Janette O'Hagan
RHI Inquiry

Her records show that she also told them that scheme claimants were "using more energy than before because it pays them to do so" and pointed out that there was "no incentive for them to be efficient".

Mrs O'Hagan said her claims were dismissed, with saying one official telling her: 'We don't think people will do that.'

Mr Hutchinson says he didn't use that phrase and he would've told Mrs O'Hagan that DETI believed measures were in place to prevent what she had been describing.

'Looking at figures now causes even more concern'

In 2013, a problem arose involving the eligibility for RHI scheme payments to installations that had received a loan form the Carbon Trust.

That was solved by restricting the amount of RHI subsidy that Carbon Trust loan recipients could receive.

It also led Mr Hutchinson to see examples of forms filled in by applicants including projected hours of use and payments.

Mr Lunny asks a question
RHI inquiry

Mr Lunny gives an example of a form for a 99kW boiler whose initial figure for hours of use is 8,640 per year, which equates to being run non-stop year round.

Mr Hutchinson confirms that what he saw in the forms caused him some concerns.

"Looking at it now it causes me even more concern than it did at the time; less so the focus on the hours - at the time it was the focus on the payment level," he says

'Don't know why we didn't clarify answers'

At a DETI event about the RHI scheme that was held during the autumn 2013 consultation period, a question was raised about whether two 99kW boilers "separated hydraulically but under the same roof" would qualify as a single or separate units under the regulations.

DETI replied that "they might be seen as separate heating systems", and would therefore qualify for the higher subsidy on offer for smaller units.

Peter Hutchinson
RHI Inquiry

Inquiry chair Sir Patrick Coghlin says that Ofgem had warned the previous year that similar scenarios could arise.

Mr Hutchinson accepts that it would have been easy for the DETI officials to contact Ofgem, the scheme's adminstrator, to clarify what the answer would have been.

"I don't know why it hasn't been clarified if it's come up at that point," he adds.

'Gaming of scheme very apparent on ground'

DETI opened a public consultation in autumn 2013 on its planned update to the RHI scheme, and a number of concerns were raised by respondents.

One - Biomass Energy Northern Ireland (BENI) - had warned in the consultation before the scheme opened in 2012 about the potential for so-called gaming of the scheme.

Burning wood pellets

Gaming is the installation of multiple small boilers instead of one large, more efficient boiler, in order to collect a higher subsidy on offer for the smaller systems.

In the 2013 consultation, BENI said that what it had warned about "is now very apparent on the ground", with a "plethora of multiple-but-separate systems" being used and a "demand to undersize boilers just to stay within the higher rate tariff".

'He was right - we were wrong'

Businessman Colin Turkington wrote to the Department of the Environment complaining that the RHI scheme was deterring farmers from adopting his company's poultry manure to energy (PM2E) system.

He identified a "perverse incentive" for farmers to install a number of small woodchip boilers rather than a larger PM2E system.

A biomass boiler

The letter was passed to DETI for reply and Mr Turkington's interpretation was rejected by the department.

The question revolves around the by-now-familiar concept of separate heating systems under a single roof.

Mr Hutchinson makes an admission: "Now, looking at it, he was right and we were wrong."

'DARD officials high-pressure salesmen for RHI scheme'

Stormont's Department of Agriculture and Rural Development (DARD) was being "high-pressure salesmen" for the RHI scheme even though it knew how profitable it was, says inquiry chair Sir Patrick Coghlin.

He says DARD was "actively pressure-selling this scheme" and wants to know why the department did not contact DETI to draw its attention to the overgenerosity of the initiative.

"Was there no communication between departments in this government? It just seems to be a totally disjointed system," he adds, questioning why that attitude was taken to the spending of public money.

Sir Patrick Coghlin
RHI Inquiry

Mr Hutchinson says officials from other departments might say that they had a "legitimate expectation that [DETI] had got our sums right in the first place".

"Maybe they just thought: 'Well, that's a DETI scheme and they're running it how they think and we're not going to point anything we think is a mistake with it.'"

Mr Hutchinson says that communication between departments has improved, and Sir Patrick responds: "That's comforting!"

'It's payback for renewable energy investments'

Cafre produced a booklet in October 2013, to which both Mr Ellis and Mr Hutchinson contributed articles.

Mr Ellis's section outlines a case study of a poultry farm in Moygashel in County Tyrone with 12 sheds.

It suggests a set-up of 12 individual small biomass boilers through the RHI scheme, rather than one or two large boilers to do the same job.

Doing so enabled the claimant to garner the maximum tariff on offer through the scheme of 6.1p per kWh, because higher subsidy was on offer for smaller boilers.

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Mr Hutchinson's section appears some 16 pages later and is, Mr Lunny explains, a fairly straightforward explanation of the mechanics of the scheme.

A final section of the leaflet, not written by Mr Hutchinson, is more of direct rallying cry to potential participants, saying: "It's payback for renewable energy investments."

Had Mr Hutchinson seen the piece on the case study, it would have "sparked a question in my mind", he says.

'Figures would've struck a nerve with me'

The College of Agriculture, Food and Rural Enterprise (Cafre) ran a number of events at which the RHI scheme was promoted.

Cafre official Cathal Ellis was heavily involved in the promotion of renewable energy at those events, and Mr Lunny introduces slides from a presentation he gave on 17 occasions.

It suggests a figure of 4.2p per kWh based on a wood pellets costing £200 a tonne, although Mr Lunny notes that pellets could be bought in bulk as cheaply as £160 a ton.

Wood pellets

Importantly, Mr Ellis's slides show that the fuel cost was cheaper than the subsidy on offer through the initiative.

Mr Hutchinson also attended those events and gave lectures at some of them, but says "I don't think I would have sat in on Cathal's at those points".

He says that the figures in Mr Ellis's presentation would have "struck a nerve" with him if he had seen them.

'Earn £1,500 for every £1,000 spent'

Sheridan & Hood and BS Holdings - firms that supplied and installed renewable heating systems, including biomass boilers - were perhaps the first firms to spot the generosity of the RHI scheme.

In order to generate sales, they produced promotional leaflets and booklets that outlined the potential rewards of joining the scheme.

£50 notes
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One of them that Mr Lunny shows the inquiry details a scenario in which a scheme claimant would collect £1,475 in a year if they spent £1,000 on biomass fuel.

Mr Hutchinson says he can't specifically remember any of the material but he does recall meeting Mr Hood.

Boiler firms' RHI promotion material outlined to inquiry

And they're off, as the inquiry's junior counsel Donal Lunny picks up were he left off yesterday afternoon.

Donal Lunny
RHI Inquiry

He had been asking Mr Hutchinson about his contacts with equipment installers and suppliers.

First up this morning, he takes the witness to some promotional material issued by Sheridan & Hood and BS Holdings, companies run by Brian Hood, who gave evidence to the committee earlier this month.

What happened yesterday at the RHI Inquiry?

BBC News Northern Ireland

Former DETI official Peter Hutchinson told the inquiry he "feels a bit sick" when he hears terms like "cash for ash" or "burn to earn" in reference to the RHI scheme.

The Senate chamber at Stormont's Parliament Buildings

He was one of the small group of civil servants involved in the scheme at the time of its inception and he spent the whole day as the sole witness.

The inquiry also heard that a dispute over data sharing between DETI and the initiative's administrator Ofgem meant that the department may have missed vital information about the use of multiple boilers by claimants.

What is the RHI Inquiry?

BBC News Northern Ireland

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

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

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, more than a year 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.

£20 notes

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.