Ireland's approach to reducing carbon emissions is a "charade" that is costing millions annually as it is buying carbon credits from other countries to "pretend we are coming in under target", according to the chairperson of the Public Accounts Committee.
Seán Fleming said it was "horrific" that €86.8m of Irish taxpayers' money had been spent purchasing carbon credits from other countries and labelled it "gross hypocrisy".
A spokesman for the Government said that the €86m was spent on carbon credits in 2008 and 2009.
It has also emerged that Ireland could have to pay €60m to "buy our way out of pretending" we are meeting renewable energy targets.
Additionally, the Department of the Environment estimates that Irish taxpayers face paying between €6m and €13m to buy more unused carbon credits so Ireland can meet its EU 2020 climate targets.
The details are contained in a letter, dated 10 June, from Mark Griffin, Secretary General of the Department of Communications, Climate Action and Environment, to the PAC.
Mr Fleming explained that the committee asked the department for an information note on the costs the State will face for not meeting the 2020 Climate Action targets and when these costs will be due.
He said: "The State's response, all of our response at Oireachtas and Government level, is entirely hypocritical when you read this letter."
The letter said that "the EU requires member states to meet their targets using unused emission credits from earlier years or to purchase credits from other member states via international markets".
BREAKING: PAC chair @SeanFlemingTD says Ireland's approach to reducing carbon emissions is a "charade" that is costing millions annually as we are buying carbon credits from other countries to "pretend we are coming in under target"— Conor McMorrow (@ConorMcMorrow) June 13, 2019
Mr Fleming said: "In simple English, if we don't meet our targets we can buy our way out of the problem by buying unused emissions from somewhere else. It's the biggest act of gross hypocrisy when it comes to the environment.
"We are saying that if we don't meet our targets we will buy unused emission credits from somebody else and pay the price so that when we come to the end of the 2020 target, we are below our target because we have unused credits in the system."
The National Treasury Management Association purchases these on behalf of the State.
"And on behalf of the State the NTMA has already spent €86.8m of Irish taxpayers' money purchasing these credits which is horrific. And that is to avoid a fine," Mr Fleming said.
The PAC also asked the department about Ireland's prospects of meeting its Climate 2020 targets.
The letter states: "The department currently estimates that the additional costs of this requirement to be in the region of €6-€13m between now and then if we don't meet the additional costs."
On renewable energy targets, the department said: "We have a target of 16% renewable energy by 2020. We have increased a lot from 2005 when we were at just 3%."
They are expecting to reach somewhere in the order of 13% by 2020.
The letter went on to say that "some years ago the Sustainable Energy Authority of Ireland estimated that we could buy our way out of that problem at a cost of anywhere between €65m and €130m.
"However in 2017, trade between Luxembourg, Lithuania and Estonia suggested the costs of the order of €22.5m per percentage point below our 16% target.
"So if we are 3% below our target, it could cost us, based on those prices, another €60m to buy our way out of pretending we are meeting environmental targets."
Mr Fleming concluded: "I want everyone who has an interest in the environment to know that it is a charade what we are doing in this country. We are buying unused credit emissions from other countries to balance our books and pretend we are coming in under target. We are doing nothing of the sort."
He said that the State should not have to spend taxpayers' money to buy our way out of these problems. "We should be doing the right thing in the first place," he said.
Minister for Communications, Climate Action and Environment Richard Bruton had previously said that it was likely to cost the State up to €150m to pay for carbon credits ahead of the 2020 deadline.
Director of Friends of the Earth Ireland, Oisín Coghlan, said the revelations show "that the cost of inaction will always be greater than the cost of action".
Speaking on RTÉ's News at One, he said the Government "has a chance to put things right" in its forthcoming climate action plan to "show how we try to make up some ground between now and 2020 and much more ground from 2030" or face fines or costs of between €2bn-€6bn if it does not meet our 2030 targets.
Mr Coghlan called for the plan to include four key measures: the target adopted to reduce carbon emissions is placed in law, the introduction of five-year carbon budgets that are adopted by the Dáil, a strong Climate Change Council to monitor the Government, and a strong parliamentary committee for carbon emissions.