“Energy efficient” homes are paying about €50 more a year for natural gas because they use more of the fuel, official figures indicate.
Research from the Central Statistics Office (CSO) shows that dwellings with the highest A and B Building Energy Ratings (BER), which are the best-insulated, use more natural gas on average for heating than those in lowest F and G brackets.
The figures indicate that A- and B-rated dwellings could be paying as much as €50 more a year for natural gas based on current prices offered by suppliers in the Republic.
According to the CSO, in 2020, A- and B-rated homes used 11,483 kilowatt hours (KWH), the unit in which natural gas is sold, against 10,965 KWH for F- and G-ranked dwellings.
This would push A- and B-rated homes’ natural gas bills to €1,171.27 a year as against €1,118.43 for their lower-ranked counterparts, if they were paying 10.2 cent a-KWH for the fuel, an average of 17 different tariffs offered by Irish suppliers.
That gap widens to about €70 a year at 13 cent KWH, the price towards which most observers believe domestic natural gas is headed this winter on the back of likely supply squeezes and possible shortages of the fuel in Europe.
At that price, higher-rated homes would pay €1,493 a year for natural gas supplies, while those in the F and G brackets would pay €1,425. Natural gas price charges vary widely according to suppliers and the different deals that each offers customers.
Dympna Corry, a statistician in the CSO’s environment and climate division, said on Monday that the research showed gas use varied more according to the type of property than its energy-efficiency rating.
She noted that, in 2020, detached houses used 16,054 KWH of natural gas, almost twice the 8,808 KWH that apartments consumed.
“F and G energy-rated dwellings had the lowest mean gas consumption figure in 2020, indicating that factors other than energy ratings, such as disposable income, whether the house was adequately heated and use of secondary heating fuels may have had an impact,” said Ms Corry.
Statisticians found that the highest-rated homes are generally bigger than those ranked lowest, and so needed more gas for heating in the first place.
Detached A- and B-rated houses had average floor areas of 194 sq m, against 124 sq m for detached properties rated F and G. “This trend of larger floor areas for more energy-efficient dwellings was evident for all household types,” Ms Corry added.
However, the research did find that better insulated homes used less heat per square metre. A- and B-rated homes consumed 89 KWH against 124 KWH for F- and G-rated properties.
Homes used more gas in 2020 than in 2019, indicating that the Covid-19 lockdowns during that spring and winter, which forced many people to stay at home, could have increased the need for heating.
However, the CSO’s figures show that demand in 2018 outstripped 2020, possibly because of a cold spell in February and March of that year.
The office found that, in 2018, detached homes used 16,672 KWH of gas, against 16,054 KWH in 2020, and 15,481 KWH in 2019. Semi-detached houses used 12,149 KWH in 2018, 11,739 KWH in 2020 and 1,118 KWH in 2019, the figures show.
The COS compared 210,500 BER audits against gas meter files in its research. Statisticians will shortly publish similar research on homes and businesses that use electricity as their main source of heat.
Their research is part of an overall exercise to develop environmental and social statistics that give information on areas including climate impact and energy poverty.