A quarter of all energy used in Ireland is consumed directly in homes. Second only to transport, and more than is used by industry.
Significant energy use of the residential sector
The residential sector accounts for a quarter of the energy used in Ireland. It is also responsible for a quarter of the energy-related CO2 emissions. From 2006 to 2014 there were significant reductions in the amount of emissions from homes. Since 2014 this trend has reversed and carbon dioxide emissions have started to increase.
The graphs below show trends in energy use in homes, broken down in different ways.
Final residential energy demand
|Year||Energy Demand||Weather Corrected Energy Demand|
Adjusting for weather
Weather variations from year to year affect energy demand, particularly for space heating. It is useful to adjust for annual weather variations by using degree-days.
Return to growth
Weather corrected residential energy demand decreased every year between 2007 and 2012, but grew in 2013, 2015 and 2016. Between 2014 and 2016, residential sector final energy consumption increased by 6.5% (3.2% per annum).
Reasons for changes
Potential reasons for the decrease in household energy use between 2007 and 2014 include:
- Improved thermal efficiency due to retrofitting and building regulations
- Reduced household incomes and expenditure, due to the economic downturn
- High energy prices
Potential reasons for the increase between 2014 and 2016 include:
- Increasing household incomes and expenditure
- Reduced energy prices, particularly of oil
Final residential energy demand by fuel type
Dominance of oil
Oil has remained the largest fuel source since 2000. It accounted for 37% of all final energy used in the residential sector in 2016. The next largest source was electricity at 25%.
Between 1990 and 2000 there was a clear switch away from solid fuels used in open fires towards oil and gas central heating systems. After 2000, fuel shares became more stable. We can see a gradual increase in shares of electricity and gas and a continuing decline in coal and peat use.
Weather corrected oil and gas use
Changes in oil use were the main source of fluctuation in overall household energy demand between 2007 and 2016. Weather corrected oil use declined by 28% between 2007 and 2014 and increased by 17% between 2014 and 2016. Weather corrected gas demand decreased by 17% between 2007 and 2014. It increased by 5% between 2014 and 2016.
A likely reason for the higher fluctuation in oil use may be the greater fluctuation in oil prices. Additionally, the majority of oil-fired dwellings are in rural areas. These areas may offer greater opportunity for fuel switching to solid fuels.
Total electricity consumption peaked in 2008. It reduced slightly between 2008 and 2016, having more than doubled between 1990 and 2008. There is evidence that the growth of large household appliances is levelling off. At the same time, there has been an increase in appliance efficiency. Additionally, there was an increase in electricity prices over the period.
Between 2005 to 2016 renewable energy grew from a low starting point, mostly from wood pellets.
Final energy by end-use
Electricity,Space Heating,67 Electricity,Water Heating,79 Electricity,Cooking,47 Electricity,Lighting and Appliances,459 Electricity,Other,25 Gas,Space Heating,405 Gas,Water Heating,145 Gas,Cooking,13 Solid Fuels,Space Heating,347 Solid Fuels,Water Heating,34 Oil,Space Heating,780 Oil,Water Heating,219 Oil,Cooking,1 Renewables,Space Heating,53 Renewables,Water Heating,30
Challenge of gathering end-use data
It's important for us to understand how energy is consumed in homes. In particular, we need information on the portion of energy consumed for the main end-uses. These include space heating, water heating, cooking, lighting and electric appliances.
We cannot collect data on energy by end-use in the same way as it is by fuel type. For example, it's not possible to use electricity meter data to tell the share used for water heating.
A new model for estimation
To estimate the split, SEAI developed a model of household energy consumption. We based it on data from the BER database. Our estimation for 2016 is: 61% of all energy used in households was for space heating, 19% for water heating, 17% for lighting & appliances, and 2% for cooking.
Energy related CO₂ emissions
Second highest source of CO2
The residential sector accounted for 24% of energy-related CO2 emissions in 2016. This includes upstream electricity emissions. The residential sector was the second largest source of CO2 emissions after transport (which accounted for 37%).
The trend for residential energy-related CO2 emissions follows the trend in energy consumption. Residential energy related CO2 emissions increased in 2015 and 2016, after a decrease between 2010 and 2014.
CO2 emissions by fuel source
The graph shows residential energy related CO2 emissions split by fuel source. Oil, gas, coal and peat are burned directly within the home. We also factor in CO2 emissions from electricity generating stations producing electricity for homes.
The emissions from electricity use in the home are the largest source of emissions by fuel type. They account for 39% of total residential CO2 emissions. Oil use was the next largest source, accounting for 31%. If we exclude electricity, oil accounted for 51% of residential CO2 emissions.
Final energy per dwelling
|Non-electric energy||Non-electric (Weather corrected)||Electricity|
In 2016 the average dwelling consumed a total of 18.5 MWh of energy – 78% from direct fuel use and 22% from electricity. Weather corrected final energy use per dwelling remained constant between 2000 and 2005. It fell by 29% between 2005 and 2014, but increased again by 5% between 2014 and 2016.
Energy related CO₂ emissions per dwelling
Overall energy related CO₂ emissions
In 2016 the average dwelling emitted 5.7 tonnes of energy-related CO2. 60% of these were from direct fuel use in the home and 40% indirectly from electricity use.
The emissions of energy-related CO2 per dwelling fell by 32% between 2005 and 2016. This compares to a reduction in energy per dwelling of 23%). Emissions from energy use in households increased by 1% in 2016. This is mainly a result of increased CO2 intensity of electricity supplied. Increased oil consumption was also a factor.
Energy related CO2 emissions per dwelling for non-electric fuel use fell by 30% between 2005 and 2016. This is primarily a result of reduced energy consumption per dwelling.
CO2 emissions from electricity use reduced by 34% in the same period. This is due to reduced electricity use and reduced carbon intensity of the electricity grid.
Energy in the Residential Sector report
Our Energy in the Residential Sector 2018 report provides detailed data and analysis. It also offers a comparison of Irish homes to those of other EU countries.