CEPA entered into its contract with DETI to offer consultancy on the RHI scheme "with some reservations", says Mr Cockburn.

He says he company wanted an interim payment "to help with our cashflow", which was then incorporated into the contract.

Image source, Getty Images

Its role in the RHI project was, according to documents from the time when the arrangement was made, to "undertake an independent economic appraisal of a Northern Ireland-specific" scheme.

A "consideration of the risks" posed in an RHI scheme was part of the CEPA's remit, as well as assessing "uncertainty", and its work was ultimately to make recommendations on "the most cost-effective structure" for a scheme.

Mr Lunny looks at CEPA's previous experience in working on renewable heat schemes.

He produces part of CEPA's proposal for work on the 2011 report, in particular a table that sets out the consultancy's previous experience that of AEA Technologies, which worked with it on the report.

Image source, RHI Inquiry

It shows CEPA's experience in various energy schemes, and AEA's particular experience in renewable heating initiatives, including the RHI scheme in Great Britain.

Mr Lunny confirms to inquiry chair Sir Patrick Coghlin that there is no suggestion that CEPA were inexperienced in the field.

It's the turn of Mark Cockburn to take the witness chair this morning.

He's a director the consultancy Cambridge Economic Policy Associates (CEPA), which was commissioned by Stormont's Department for Enterprise, Trade and Investment (DETI) to prepare a report in 2011 on how the RHI scheme should be set up (click to download), external.

Image source, RHI Inquiry

For fans of our Stormont Live coverage from way back in the day, you might remember that Mr Cockburn appeared before the Northern Ireland Assembly's Public Accounts Committee last year.

He's due to give evidence to this inquiry throughout today, tomorrow and on Tuesday, too.

Inquiry counsel Donal Lunny is posing the questions this morning and takes Mr Cockburn through some of his written evidence, which he has supplied on behalf of CEPA.

BBC News Northern Ireland

The Treasury did not tell officials in Northern Ireland about restrictions on RHI scheme funding, the inquiry heard.

Image source, Reuters

It was told officials running the equivalent scheme in Great Britain were clearly told of the restrictions that meant any overspend would have to be met by department funding.

Junior counsel to the inquiry Joseph Aiken said the warning may have "slipped through the net".

BBC News Northern Ireland

An independent inquiry into the RHI scandal was established in January 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.

Image source, Pacemaker

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

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.

Public and political anger erupted when the scale of the overspend emerged.

The Democratic Unionist Party (DUP) leader Arlene Foster (below) had been the minister in charge of the Stormont department that set up the RHI scheme in 2012 and she faced calls in to stand down as Northern Ireland's first minister in December last year.

Image source, Getty Images

She refused, 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.

By doing so, he brought about the collapse of the Northern Ireland Executive. Now, nearing a full 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.

The budget of the RHI scheme ran out of control because of critical flaws in the way it was set up - the most recent estimate for the overspend was set at £700m, if permanent cost controls aren't introduced.

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.

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

Need a quick refresher on what the RHI scandal is all about? Here goes...

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

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.

Welcome along to Parliament Buildings at Stormont for another day of the RHI Inquiry.

Proceedings will begin shortly, so stick with us throughout the day for a live video stream and text commentary of all the goings on.