A home retrofitting scheme for low-income households has been criticised in an official report for failing to set out what it aimed to achieve or gather sufficient data to show what it accomplished.
The European Court of Auditors said the €20m-a-year Better Energy Warmer Homes scheme was not run in a cost-effective way and, from what limited information was available, did not result in improved energy efficiency ratings for more than half the homes renovated.
The auditors were also critical of the decision to reduce State funding for the scheme by the same amount as the EU put into it so that EU investment resulted in no increase in the money available.
Schemes in Italy, Bulgaria, Lithuania, Czech Republic and Ireland were examined by the auditors, who looked specifically at the use of the Better Energy Warmer Homes scheme in the east and south of the country.
In Ireland, where the scheme is run by the Sustainable Energy Authority of Ireland (SEAI), they noted that its stated aim was to support "comprehensive and ambitious energy efficiency improvements resulting in at least an improvement in one energy efficiency rating".
The report stated: "In practice, projects did not define any energy saving objective, did not report on energy saved and, for more than half of supported households, did not improve energy ratings."
It said the 'first come, first served' approach to grants meant homes were not properly assessed to ensure that funds were used in the most efficient way.
"All member states we visited - except Ireland - required projects of a certain ambition by setting minimum energy ratings buildings should reach after works and or minimum percentages of energy savings that projects should deliver," it said.
It added: "In Ireland, the reported indicators 'number of households with improved energy consumption classification' and 'total amount of eligible expenditure' reported to the Commission are not reliable.
"Following our audit and Commission observations, the Irish authorities reported that energy ratings did not improve for 52pc of households renovated by the Better Energy Warmer Home Schemes in 2017.
"The Irish authorities are currently reviewing the projects for households renovated in 2014, 2015, 2016 and 2018 to verify how many did not have their energy rating improved."
The report also shows that just 27pc of the money allocated for the scheme to cover the 2014-2020 period had been spent by the end of 2018.
The SEAI said the assessment criteria used by the auditors was narrow.
"The programme delivers many benefits to the subject homeowners including improved comfort, quality of life, and health," it said, stressing it had improved 142,000 homes since the year 2000.
"This audit addresses the scheme in terms of energy efficiency only and not other benefits such as energy poverty reductions."
It said the scheme underwent a significant change in mid-2018. "This has resulted in deeper retrofits and more dramatic results for homeowners."
It also said there had been "substantial improvements made to the energy ratings of many of those participating".
It added that since 2018, the share of State funding for the scheme had increased each year up to €52.8m in the current year.