Environmental Sustainability: trends in emissions and energy consumption

Patrick Malone and Conor Callaghan

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Key Point

In 2017 total emissions per capita in Ireland amounted to 13 tonnes of Co2 equivalents[1]: representing a decrease of 4 tonnes of Co2 equivalents since 2005. Total emissions in Ireland in 2017 were 4 tonnes above the EU average of 9 tonnes of Co2 equivalents. During the recession and its aftermath total emissions per capita decreased by 3 tonnes of Co2 equivalents between the years 2008 and 2014 before increasing to over 13 tonnes in 2017. The decline in emissions during the Great Recession is reflective of the overall decrease in economic outputs and consumption during these years (2008 to 2012). The sectors accounting for the largest shares of energy consumption included Transport (43%), Residential (22%) and Industry (21%). Energy consumption across all sectors dropped by 2Million tonnes of oil equivalent (Mtoe)[2] between the years 2008 and 2011 before increasing slightly to 12Mtoe in 2017. In terms of energy consumption by fuel type, oil and gas fuels continue to account for the largest share of energy consumption: accounting for almost 80% of total fuel consumed in 2017. Between the years 2008 and 2012 the consumption of oil decreased by 3Mtoe before increasing to 7Mtoe in 2017. The consumption of gas increased by 0.2Mtoe between the years 2008 and 2010. However, gas consumption decreased in the years following by 1Mtoe (2010 to 2014) before increasing back to pre-recession levels at 4Mtoe. By contrast renewable energies increased steadily over the last decade overtaking tradition fuels such as coal and peat. In 2017, 1.35Mtoe of renewable energy was consumed: an increase of nearly 1Mtoe, or more than 250% since 2005. 

Policy Context

Figure 1 shows the tonnes of Co2 equivalents per capita between the years 2007 and 2017. In per capita terms, total emissions decreased marginally from 17 tonnes in 2005 to 16m tonnes in 2008. During the Great Recession and its aftermath total emissions per capita fell by 3 tonnes of Co2 equivalents per capita: decreasing from 16 tonnes in 2008 to 13 tonnes in 2014. The decrease in total emissions per capita reflects the overall decline in economic outputs and consumption during the recessionary years (2008 to 2012). The level of total emissions stabilised between the years 2011 and 2013 at 13 tonnes of Co2 emissions per capita. However, once economic growth resumed, emissions per capita rose from 12.7 tonnes in 2014 to 13.3 tonnes in 2017. This highlights the significant structural issues that exist within the Irish economy in terms of reliance on Co2 equivalents.           

When compared to the EU average, the total emissions produced per capita in Ireland are much higher. In 2005, Ireland’s total emissions per capita were 6 tonnes higher than the EU average of 11 tonnes of Co2 equivalents. Since 2005, the EU average of Co2 equivalents per capita has decreased slightly by 2 tonnes: decreasing from 11 tonnes in 2005 to 9 tonnes of Co2 equivalent per capita in 2017. However, a gap still remains between the Irish and EU average in terms of the total emissions produced per capita. In 2017, Ireland produced 13 tonnes Co2 equivalents per capita, whereas the EU average was 9 tonnes.

Figure 1: EU and Irish C02 Emissions Per Capita 2005 to 2017

Source: Eurostat (2019)

Energy Consumption and Trends by Sector

Figure 2 shows the share of energy consumption by sector. In 2017, the sectors consuming the largest share of energy resources were Transport (43%), Residential (22%) and Industry (21%). The sectors with the lowest levels of energy consumption were Services (12%) and Agriculture and Fisheries (2%).

Figure 2 Share of Energy Consumption by Sector 2017

Source: SEAI (2019)

Figure 3 shows trends in energy consumption by sector between the years 2007 and 2018. Between the years 2008 and 2017, total energy consumption across all sectors decreased slightly by 1 million tonnes of oil equivalent (Mtoe): decreasing from 13Mtoe in 2008 to 12Mtoe in 2017.

In 2017, the Transport Sector accounted for the largest share of energy consumption at 5Mtoe. During the Great recession, the transport sector decreased by 1Mtoe: decreasing from 5Mtoe in 2008 to 4MToe in 2012. In the years of economic recovery, the transport sector energy consumption increased once again to 5Mtoe in 2017.

The industrial sector also accounts for a large share of total energy consumption: consuming 2.5Mtoe in 2017. Between the years 2008 and 2012 total industrial consumption decreased by 0.4Mtoe. In more recent years, the consumption of energy in this sector has increased steadily, from 2Mtoe in 2012 to 2.5Mtoe in 2017.

The residential sector also accounted for a sizable share of energy consumption at 2.6Mtoes in 2017: representing a decrease of 0.50 Mtoe on 2008. Energy consumption in this sector fell slightly by 0.4Mtoe between the years 2008 and 2012.

Between the years 2008 and 2014, the energy consumption of the Services Sector decreased by 0.5 Mtoe and then increased to 1.4Mtoe in 2017 (+0.16Mtoe). Energy consumption in the agricultural sector has decreased marginally overtime from 0.36Mtoe in 2008 to 0.24Mtoe in 2017.  

Figure 3: Energy Consumption by Sector 2007-2017

Source: SEAI (2019)

Energy Consumption and Trends by Fuel Type 2005-2017

Figure 4 shows the share of energy consumption by fuel type. In 2017, the fuel types accounting for the largest shares of energy consumption included Oil (48%), Gas (30%), Renewables (9%) and Coal (7%). The fuel types with the lowest share of energy consumption included Peat (5%) and Wastes Non-Renewables (1%).

Figure 4: Energy Consumption by Fuel type 2017

Source: SEAI (2019)

Figure 5 shows trends in primary energy consumption by fuel type between the years 2005 and 2017. Primary energy includes the raw fuels that are used for transformation processes such as electricity generation and oil refining. In 2005 total oil consumption amounted to 9Mtoe. The consumption of oil fell steadily during the recession by 3Mtoe, to 6Mtoe in 2012. In more recent times of economic growth, oil consumption has begun to rise once again: increasing from 6Mtoe in 2012 to 7Mtoe in 2017.

Between the years 2005 and 2010, the consumption of gas has risen steadily by 1Mtoe: increasing from 3.5Mtoe in 2005 to 5Mtoe in 2010 (+1.5Mtoe). However, gas consumption decreased slightly by 1Mtoe between the years 2010 and 2013, before increasing to 4Mtoe in 2017.

Figure 5: Primary Energy Consumption by Fuel Type

Source: SEAI (2019)

By contrast to oil and gas consumption, the use of renewable energy has increased steadily: rising from 0.40Mtoe in 2005 to over 1Mtoe in 2017 (+0.6Mtoe). Renewable energies have overtaken the more traditional fuel types’ coal and peat over the last decade. Coal consumption has fallen intermittently overtime: decreasing from 1.4Mtoe in 2008 to 1.1Mtoe in 2017 (-0.3Mtoe). The level of peat consumption has been static overtime: decreasing from 0.8Mtoe in 2005 to 0.7Mtoe in 2017.


Eurostat (2019a) Greenhouse gas emissions per capita [Online] Available at: https://ec.europa.eu/eurostat/tgm/graph.do?tab=graph&plugin=1&pcode=t2020_rd300&language=en&toolbox=data

Eurostat (2019b) Glossary: Tonnes of Oil Equivalent [Online] Available at: https://ec.europa.eu/eurostat/statisticsexplained/index.php/Glossary:Tonnes_of_oil_equivalent_(toe)

Sustainable Energy Authority of Ireland [SEAI] (2019) Energy Use Overview [Online] Available at: https://www.seai.ie/resources/seai-statistics/key-statistics/energy-use-overview/

[1] A wide range of gasses known as greenhouse gases contribute to climate change. This indicator shows trends in man-made emissions of the ‘Koyoto basket’ of greenhouse gases. The ‘Koyoto basket includes: Carbon Dioxide (Co2), Methane (CH4), Nitrous Oxide (N2O), F-gases (hydrofluro carbons, nitrogen trifluuoride (NF3) and sulphur hexafluoride (SF6)). These gases are aggregated into a single unit, using gas specific global warming potential factors (GWP) factors and are expressed as units of Co2 equivalents (Eurostat, 2019a).

[2] Tonnes of oil equivalent are a standardised unit of energy. By definition, it is equivalent to the approximate amount of energy that can be extracted from one tonne of crude oil (Eurostat, 2019b).

About author

Patrick Malone

Email: patrick.malone@ucd.ie