Energy use in residential properties is falling despite a significant increase in the number of households, according to the Sustainable Energy Authority of Ireland (SEAI).
Residential energy usage fell 8 per cent between 2006 and 2011 and during the same five-year period energy usage per dwelling fell 18 per cent.
Head of low carbon technologies, Kevin O’Rourke, said about half of the drop could be attributed to improvements in the quality of residential buildings.
This includes better insulation, more efficient heating systems and the retrofitting of some 200,000 houses with attic insulation, draught proofing, energy efficient lighting and cavity wall insulation.
This has lead to an annual energy cost saving of €56 millionand a shift from lower E, F and G BER (Building Energy Rating) grades for such properties to higher C and D grades.
Mr O’Rourke said the figures provided evidence that the building regulations and retrofit programmes were working. However, he said the latter needed to be extended “further and deeper” in order to meet national targets.
Mr O’Rourke said 2006 had marked a “turning point” in energy consumption.
He said in the following five-years the pace of energy efficiency improvements had almost trebled.
Mr O’Rourke changes in to “behaviour and choice” were also leading to a reduction in energy use, although the reasons behind these changes are unclear.
Average household expenditure on energy fell by 2.8 per cent during the study period.
Some 1.65 million households spent approximately €3 billion on energy during 2011, or an average of around €2,000 per home.
During the period energy prices increased, which could have prompted people to use less electricity and heating. However, Mr O’Rourke, said that further research is needed clarify whether this is true.
“The ESRI has done some work,” he said. “It doesn’t really get under the skin of the motives of individuals”.
The report notes that consumption tends not to be “sensitive to energy prices,” particularly in the short-term, and cites a study which found that a 10 per cent price increase lead to 0.7 per cent drop in usage.
Mr O’Rourke said that an increase in people’s awareness of energy consumption and how to save it may be another reason for the usage drop associated with behaviour.