Renewable Heat Incentive Inquiry examining botched energy scheme
DETI official Stuart Wightman answers questions from the inquiry
Inquiry set up after public concern over scheme's huge projected overspend
Retired Court of Appeal judge Sir Patrick Coghlin chairing inquiry at Stormont
Public evidence sessions expected to last until well into 2018
Mr Aiken winds things up for today - it looks like Mr Wightman will be back in the hotseat tomorrow afternoon to finish his evidence.
Tomorrow's morning session introduces a new face to the inquiry - Chris Johnston from the Department of Agriculture, Environment and Rural Affairs will be answering questions.
Join us at the usual time of 09:45.
BBC News NI
A civil servant who helped run the RHI scheme said he wished that he had not held informal conversations with the poultry and energy industries about proposed changes to the initiative.
The informal engagement with poultry giant Moy Park, some farmers and renewable heat firms took the place of a wider formal consultation.
Image source, Pacemaker"I realise that some of the engagement does look naïve now, given hindsight," said Mr Wightman.
"I totally look back now and say I wish I hadn't done that."
In February 2015, Mr Wightman outlined to Moy Park some of the proposed changes that the department was considering for the RHI scheme.
In an email to Moy Park colleagues afterwards, Mr Mark said that Mr Wightman's guidance gave the company a "firm basis" for RHI scheme investment "until at least October 2015" and a "positive look forward" beyond that.
Image source, Getty ImagesMr Aiken suggests that Mr Mark's email could be read as advising that potential applicants get signed up to the scheme before October if the wanted to get the most lucrative subsidy.
He adds that as a result of the conversation with Mr Wightman, Moy Park received "a piece of information that's known to nobody" - that the subsidies from the scheme were potentially going to be reduced.
Mr Wightman accepts that point.
Mr Wightman came up with ideas that he felt would offer protection to the RHI scheme's budget but Dr McLean was quick to spot their flaws when the inquiry discussed them last week.
The renewable energy expert says he "can't understand what strategy you were pursuing, what thought process you were going through in this work".
Image source, RHI Inquiry"Were you just sitting in the office, cup of coffee, and: "This seems like a good idea today'? I just don't see where they're coming from."
And Dame Una (above) weighs in too, asking: "Did you ever think we need to check out how this would work in practice or what the consequences would be?"
She says the policies seem to have been drawn up "in search of evidence rather than evidence driving the policy".
Image source, Getty ImagesDr MacLean questions how Mr Wightman's claim that his strength of "working effectively with a diverse range of stakeholders" is compatible with his insistence that he didn't see red flags of how the RHI scheme was offering lucrative returns.
The witness says he didn't have time "to be as proactive as I would've liked" and adds that "turkeys weren't going to vote for Christmas in terms of alerting me to the fact that the scheme was generous".
Mr Wightman wrote an article about the RHI scheme for booklet that was distributed at Department of Agriculture and Rural development events.
In the booklet there was a case study of a pig farmer who was an claiming from the scheme.
The farmer was getting £21,000 a year from the scheme, even though his heating bill was only £19,495 - as Mr Aiken puts it, "he's getting free heat and two grand in his hand for 20 years".
Image source, Getty ImagesInquiry panel member Dr Keith MacLean wants to know how the case study "and so many other things that we've seen in evidence to the inquiry was not obvious to you".
"That would've been obvious if I'd read the article," says the witness., adding that it "now looks very shortsighted that I didn't pick it up".
"To be perfectly frank, at that point in time I just did not have time to do that role," he adds.
Image source, RHI inquiryMr Aiken asks whether Mr Wightman feels he should've got "specific approval... the moment you decided on" changing the cost control plan for the RHI scheme that the public had been consulted on.
He suggests that the witness should have recognised that "significance" of making such a change and thought: "I'd better run that past my boss."
Mr Wightman says he thinks he would've discussed the issue with DETI's energy boss but he doesn't have a memory of when that might have been.
In 2015, DETI changed its plan for a cost control mechanism for the RHI scheme, deciding to run with an annual reduction of the subsidies on offer over the course of two years.
That was not what had been publicly consulted on by the department on 2013.
Mr Wightman says he looked at the original plan and "could not see it working" so he decided to draw up a new proposal.
Image source, PAInquiry chair Sir Patrick says the original cost control "had not been heavily criticised" and he queries whether the decision to draw up a new plan should in fact have been taken by a more senior figure: "Possibly... was it something that should've gone to the minister (Arlene Foster (above))?"
Mr Wightman explains that what he was doing was "early policy proposals", which would've ultimately gone to the minister for approval.
But as the "crisis" surrounding the scheme deepened, he says, "it never got to that stage".
Mr Wightman's financial forecasts for the scheme in 2015 show the costs of the RHI scheme leveling-off.
Mr Aiken reminds the inquiry that when he asked DETI official Seamus Hughes (seen below) - who worked under Mr Wightman on the running of the scheme - about the forecasts that his answer that "it was Mr Wightman who did all the maths".
Image source, RHI InquiryMr Wightman says there was a spreadsheet in existence before he came to the department and there were assumptions in it about "some sort of saturation point".
"To be fair, when I came in I wouldn't have had the knowledge to challenge that," he says, and it was thought that at some stage in the future applications would "effectively dry up".
Image source, Getty ImagesMr Wightman has claimed in his witness statement that he was not aware in 2014 of the unique funding arrangement for the RHI scheme and that the department would have to cover any overspend.
But Mr Aiken digs out documents that explain the funding plan and it turns out that Mr Wightman attached those to emails he sent to colleagues.
"Yes, that's a fact," the witness acknowledges.
Ms O'Hagan sent other emails to DETI in which she flagged up the key flaw in the RHI scheme.
Mr Aiken says the emails and other documents suggest that Mr Wightman "ought to have known" about the potential for claimants to receive excessive payments.
Image source, Getty ImagesMr Wightman accepts that he ultimately received the emails but they were among "quite a few emails I was getting at that time".
"I really regret that I didn't pick up on it - you don't have to be an engineer to pick up the language she's using about how serious her claims were," he adds.
In his witness statement, Mr Wightman says that in summer 2015 he wasn't aware that the RHI scheme was "providing poor value for money" and was "providing recipients with excessive payments".
But in the handover note, mentioned frequently this morning, which was drawn up by one of his predecessors in running the scheme and outlined key areas for consideration for those subsequently working on it, explained that there was a danger that subsidies "could become overgenerous" and the issue should be looked at "as a matter of urgency".
Image source, RHI InquiryIn addition to that, the so-called whistleblower, who tried to draw the then DETI minister Arlene Foster's attention to a key flaw in the scheme in 2013, also flagged the issue in an email to the department in June 2014.
Mr Wightman ultimately received the email, in which Ms O'Hagan said that "what we are seeing on the ground... is that buildings are using more energy than before it pays them to do so", with some "heating buildings all years round with the windows open everywhere".
The witness acknowledges that "for one reason or another I didn't pick up on those flags".
Busy opening session of the day and after a bite to eat we'll be back for more from 14:00.
Mr Wightman admits he was "surprised" by some of the ways in which the RHI scheme was "gamed" by some claimants.
Mr Aiken queries what "market intelligence" DETI had and how the department ensured it was not "commercially naive" about what ways the "man on the street" could come up with to bend the scheme's rules.
Image source, Getty ImagesThe witness accepts that there "would've been a bit of naivety on my part that people would've went down certain routes to game the system".
He says he didn't receive any training that would've made him more aware of the potential for abuse of the scheme and in his previous civil service role he didn't have contact with private companies "that were trying to make a profit".
Some of the engagement with industry about the RHI scheme "does look naive now" but it was "done for the right reasons at the time", he says.
"I totally look back now and say: 'I wish I hadn't done that.'"
Image source, RHI InquiryIn his witness statement, Mr Wightman says the "key to my success was working effectively with a diverse range of stakeholders to develop new policies".
Asked by inquiry panellist Dame Una O'Brien if that was his "preferred way of working", he says it was.
Mr Aiken suggests that by the summer of 2015 the civil service would have seen the RHI scheme as "a seriously wounded animal crawling along".
It didn't want a final blow to be struck before the poor wee thing could be saved.
"Why would you hand out the weapons to allow that seriously wounded animal to have its life ended?" he queries.
Mr Wightman says the officials wanted to see their changes to go through as smoothly as possible "and one of the biggest players is Moy Park and they could potentially make life difficult for us".
Image source, RHI InquiryOne of the "key questions" for the inquiry, says Mr Aiken, is to what extent DETI's consultation with industry about the RHI scheme was known to senior managers and whether it was authorised by them.
Mr Wightman says DETI's then energy boss John Mills knew he was in touch with industry but he can't remember having a discussion with him in which he laid out the changes were being revealed to industry.
Dr MacLean suggests the informal consultation in place of a more formal process was "even more likely to raise the potential of challenge in that it was a selective process that meant that not everybody was informed".
"The whole point of a public consultation is that it goes out to everybody at the same time to give them the same opportunity," he adds, saying that the informal process was selective and could've been considered discriminatory.
Image source, Getty ImagesMr Wightman says the major poultry producer Moy Park was consulted because its farmers made up such a large percentage of RHI scheme beneficiaries and it was "imperative" for DETI to get "an idea of the likely demand that was coming".
The poultry industry was "one of the key players" and DETI as aware of the "impact" it could have in helping the department to "achieve our renewable heat targets", says Mr Wightman.
His discussions with industry were not done "in the absence of a public consultation" he insists, although he accepts that there were risks with it.
In May 2015, it had been decided within DETI to introduce tiered tariffs to the RHI scheme.
Tiering is a way of controlling the cost of the scheme and works by dropping the tariff on offer once a certain limit of usage has been reached.
In June, Mr Wightman prepared a draft paper for a public consultation on the introduction of tiering but the decision was subsequently taken not to hold a formal consultation process.
Mr Wightman's inforal consultation with industry in July 2015 "led to increased awareness of the proposed changes" to the the RHI scheme, he accepts.
But he says there's "no evidence" that it resulted in an increase in applications during July or August 2015.
He was not aware at that stage that the scheme was so lucrative and claimants were receiving far greater payments that had ever been intended.
"At that time we still thought that the RHI was a worthwhile scheme," he says in his statement.