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
Source: SEAI

Electricity generated

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.

Generation efficiency

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

 GasCoalPeatRenewablesOilWastes Non-Renewable
2000 1828 1430 491 117 1039 0
2001 1855 1517 549 104 1232 0
2002 2069 1468 554 131 898 0
2003 2356 1327 511 109 607 0
2004 2251 1365 337 135 769 0
2005 2044 1422 499 180 794 0
2006 2411 1217 463 233 686 0
2007 2737 1172 459 270 398 0
2008 2811 991 578 341 3550
2009 2759 775 568 393 214 0
2010 3025 868 492 368 137 0
2011 2498 913 481 516 55 0
2012 2269 1160 559 527 56 18
2013 2098 970 507 561 43 23
2014 1973 942 550 631 60 25
2015 1899 1127 554 749 86 25
2016 2342 1101 522 747 68 25
Source: SEAI

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 %
200036
200135
200237
200339
200440
200541
200642
200744
200845
200945
201045
201147
201246
201348
201449
201549
201648
Source: SEAI

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

 GasRenewablesCoalPeatOilWastes Non-Renewable
2000 797 102586 152 399 0
2001 787 88 607 189 447 0
2002 931 119 587 179 321 0
2003 1121 98 533 174 211 0
2004 1109 120 536 128 276 0
2005 995 161 549 211 287 0
2006 1186 213 506 184 244 0
2007 1330 240 473 187 165 0
2008 1438 309 442 237 1470
2009 1402 353 344 226 79 0
2010 1558 321 306 187 52 0
2011 1327 466 339 283 20 0
2012 1216 452 432 210 20 4
2013 1129 484 368 196 16 6
2014 1087 550 340 215 22 6
2015 1064 676 419 217 35 6
2016 1318 646 404 199 25 6
Source: SEAI

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 %
20002.4
20012.4
20022.5
20032.4
20042.5
20052.2
20065.5
20076.1
20086.1
20096.4
20106.8
20117.1
20127.7
20137.4
20147.4
20157.5
20167.5
Source: SEAI

Higher efficiency

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

 CoalPeatOilNatural GasWastes Non-Renewable
2000282 110 163 2150
2001 288 119 187 2120
2002 269 116 131 2270
2003 236 103 86 2500
2004 228 74 105 2300
2005 230 101 104 2010
2006 191 88 87 2300
2007 177 84 49 2510
2008 146 106 422530
2009 121 111 27 2630
2010 133 93 17 2860
2011 146 94 7 2430
2012 187 112 7 222 2
2013 155 102 5 2032
2014 147 109 8 189 2
2015 171 104 10 177 2
2016 163 97 8 2102
Source: SEAI

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.