Science & Technology in Action

16th Edition

Decarbonising our electricity supply


Jnr Science Cert
Politics & Society
Ireland’s target, following the Paris Agreement in 2015, is to have 40% renewable electricity by 2020, increasing to 70% by 2030. There are separate targets for the other energy sectors: transport and heat. The purpose of all the agreements and targets is to limit global temperature rise to 1.5°C above pre-industrial levels. The best climate models indicate that a rise of more than 1.5°C would have severe climate consequences.

Available downloads

The full lessons along with a supporting toolkit are available in three different formats, A4, A3 and as a Powerpoint deck.

Lesson excerpt

What is meant by decarbonising?

Decarbonising means replacing fossil fuels with sustainable energy sources. Most of our energy is generated from fossil fuels: coal, oil and gas. When they are burned the main products are carbon dioxide and water. Since the beginning of the Industrial Revolution (ca. 1760) atmospheric carbon dioxide has increased from 280 ppm to 420 ppm. The extra carbon dioxide (CO2) is a major contributor to the ‘enhanced greenhouse effect’, raising global temperatures by approximately 1°C; most of the increase occurred in the past 100 years.

Reasons for the rise in carbon dioxide

Even today, most of our energy requirements are derived from fossil fuels, further increasing atmospheric CO2. The following are the main reasons for the increased use of fossil fuels:
    • The increase in the global population from less than 1 billion (in 1800) to 7.8 billion in 2020, means that more energy is needed for cooking, heating, etc.
    • The growth in factories and the mechanisation of work, requires more energy.
    • The global expectation of ever higher standards of living, with more labour-saving devices, all require more energy.
    • Urbanisation and the increased separation of homes from places of work, make commuting necessary and require more energy.
Of course, many of these changes did improve people’s standard of living. Life expectancy and general health improved, mainly due to better food, better medical treatment and better understanding of the causes of disease. In the past 220 years or so the global population has grown 7.6 times larger but the global energy use has become 27 times larger. Global energy is shared very unequally. People in the more developed countries have 10 to 20 times more energy per head of population, than those in the poorer nations.

True or False?

  1. The level of carbon dioxide in the atmosphere has increased from 280 ppm in 1800 to 420 ppm today. true
  2. CO2 and N2O are both greenhouse gases. true
  3. The increase in energy demand is proportional to the increase in the global population. false
  4. People in developed countries use 10 to 20 times more energy than people in poor countries. true
  5. Solar and wind energy are available all the time. false
  6. Burning natural gas produces 48% less CO2 than burning coal. true
  7. The European Green Deal aims to decarbonise the energy sector in Europe by 2030. false
  8. The 24 hydroelectric power stations in the country can meet 20% of the overall electricity demand. false
  9. The three coal-fired generators at Moneypoint are due to be decommissioned by 2025. true
  10. In the last 20 years wind energy capacity in Ireland has grown about 30 times greater. true