Modern societies are dependent on reliable and secure supplies of electricity. Electricity generation accounts for a third of all primary energy use in Ireland.
Energy flow for electricity generation
Natural Gas Inputs,Total Fuel Inputs,48.5 Oil Inputs,Total Fuel Inputs,1.7 Coal Inputs,Total Fuel Inputs,22.9 Peat Inputs,Total Fuel Inputs,10.8 Wind Inputs,Total Fuel Inputs,11 Hydro Inputs,Total Fuel Inputs,1.2 Other Renewables and Wastes Inputs,Total Fuel Inputs,3.9 Total Fuel Inputs,Electricity Transformation Losses,46.6 Total Fuel Inputs,Gross Electricity Consumption,53.4 Gross Electricity Consumption,Natural Gas Consumption,27 Gross Electricity Consumption,Wind,10.9 Gross Electricity Consumption,Coal,8.3 Gross Electricity Consumption,Peat,4.1 Gross Electricity Consumption,Hydro,1.2 Gross Electricity Consumption,Other Renewables and Wastes,1.3 Gross Electricity Consumption,Oil,0.5
On the left hand side are the fuel inputs to electricity generation. Natural gas was the largest energy input, followed by coal and wind. On the right hand side are the amounts of electricity generated by each of the fuel inputs, and the total energy lost during electricity generation. Natural gas was responsible for the largest share of electricity generated, but wind was the next largest share, ahead of coal.
There is a significant difference in the shares of electricity generated by fuel compared to the fuel inputs. This is due to the different efficiencies of generating electricity in different processes. Generating electricity in traditional thermal power plants using coal, peat or biomass has low efficiency. Electricity generated from wind and hydro is 100% efficient.
Electricity transformation losses accounted for 47% of all fuel inputs in 2016. Therefore the electricity generation efficiency was 53%. This means that just a little over a half of all the energy used to generate electricity ends up as electricity.
Primary inputs to electricity generation
The graph shows the primary energy inputs to electricity generation by fuel type.
Importance of natural gas
Natural gas has been the largest input to electricity generation since the late 1990s. Its use declined after 2010, due partly to increased use of wind generation. Gas accounted for 49% of inputs in 2016. There was an increase in gas in 2016. This was partly due to increased electricity exports to the UK and to reduced generation from wind and hydro.
Coal remained the second largest fuel input in 2016. Coal and peat accounted for 34% of fuel inputs to electricity generation in 2016. Renewables accounted for 16% of fuel input in 2016. Oil has been almost fully phased out of electricity generation since 2011
Electricity imports and exports
Electricity can be imported or exported between Ireland and the UK over interconnectors. Ireland changed from being a net importer to a net exporter of electricity in 2016. This placed more demand on the Irish generation fleet in 2016.
Efficiency of electricity supply
|Efficiency of electricity supply %|
Generation efficiency and supply efficiency
Electricity supply efficiency differs from electricity generation efficiency as it includes:
- Losses from transmission and distribution of electricity on the network
- Consumption of electricity in power plants which are considered as losses
As it includes these losses, efficiency of supply is less than efficiency of generation.
Improvements in efficiency
Conventional thermal power plants have low generation efficiencies. Before 2000, electricity was produced mostly from these generators. Supply efficiency was less than 35%.
The supply efficiency began to improve after the year 2000 due to two factors. The first was the commissioning of modern gas fired turbines. They have higher generation efficiencies of 50-55%.
The second is the growth in wind powered electricity, which does not consume fuel so is 100% efficient. Despite this improvement, in 2016 the supply efficiency was just 48%. This means we lost 52% of all primary energy input into the electricity generation system.
Electricity generated by fuel
Natural gas was the largest source of electricity generated, accounting for 51% of all electricity generated in 2016. The amount of electricity generated from renewables grew from just 2% in 2000 to 25% in 2016. Renewables make up a much larger share of electricity generated than fuel inputs, as wind and hydro-power are 100% efficient.
Combined Heat and Power
|Combined Heat and Power %|
In conventional electricity generation, we typically lose 60% of input energy as waste heat. Combined Heat and Power (CHP) systems channel this extra heat to generate heat and electricity in a single process. CHP plant efficiency is usually 20% to 25% higher than heat-only boilers and conventional power stations combined.
CHP can also avoid some of the transmission losses incurred by centralised generation. In 2016 7.5% of Irelands electricity was generated through CHP.
CO₂ emissions intensity of electricity
|Coal||Peat||Oil||Natural Gas||Wastes Non-Renewable|
Trend in electricity CO2 intensity
Carbon dioxide intensity of electricity has reduced since the 1990s. This is due to increased use of higher efficiency gas turbines and zero carbon renewable generation. We are also using less high carbon intensity fuels in low efficiency processes such as coal, oil and peat generation.
Coal and peat
Coal and peat continue to be used for power generation. The result of this is that the carbon intensity of the Irish electricity was the fourth highest in the EU in 2016. In 2016 coal and peat accounted for 54% of carbon emissions from electricity generation, despite only accounting for 23% of electricity generated.
Energy in Ireland
See the download below for more information on electricity in Ireland.