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Let's start with some background. Why do we talk about 1.5?
In the Paris Agreement at the end of 2015, 195 countries agreed to hold the average temperature increase below 2°C and to make efforts to limit it to 1.5°C. It was a major diplomatic and environmental achievement. 🎆👏🏽
In the Paris Agreement at the end of 2015, 195 countries agreed to hold the average temperature increase below 2°C and to make efforts to limit it to 1.5°C. It was a major diplomatic and environmental achievement. 🎆👏🏽
The IPCC was asked for a report on the effects of global warming of 1.5°C and the possible pathways that would avoid exceeding this threshold. The effort was huge: 224 authors reviewed more than 6,000 scientific articles and more than 42,000 comments from expert reviewers.
The main conclusion of the report is that even the best-case scenario (not exceeding 1.5ºC) would lead to significant consequences for health 😷, spread of diseases 🤒, extreme heat 🥵, availability of drinking water💧, biodiversity 🦋, ecosystems 🌳, etc.
The report also states that we are diverting from the scenarios that would lead to 1.5ºC. We need to make quick, ambitious and unprecedented changes in all the aspects of society.
Talking about Climate Emergency is no exaggeration at all.
Talking about Climate Emergency is no exaggeration at all.
1.5ºC scenarios consider improvements in energy consumption and efficiency, fugitive emissions, fossil fuel switching and low-GHG energies: renewables, nuclear and fossil fuel with CO₂ capture and storage (CCS). All are valid OPTIONS. None is essential.
In this line, the investment projection between 2016 and 2050 for each electricity generation technology is quite variable. All of them include a low range with quite a low investment. The exceptions are grid and storage systems, with a greater expenditure projected in all cases.
Comparing the options, the IPCC report highlights that the political, economic, social, and technical feasibility of solar energy, wind energy and electricity storage technologies has improved dramatically over the past few years. Nuclear energy and CCS technologies have not.
Many scenarios project an increase in the nuclear contribution from 2020 to 2050. However, some of them project a decrease of up to 64%. It is also important to note that the precise final value will depend on societal preferences. We have a say in this!
All the scenarios considered achieve the goal of 1.5ºC. There are 450 nuclear reactors currently. The same 2050 temperature goal can be reached by multiplying that number by five (more than 2,200 reactors) or by reducing it to 160.
Could it be even lower? It is possible, but no scenario describes it, since they are based on today's reality. When the study was made, 50 reactors were under 10 years old and 60 under construction. Probably all of them will still be operational in 2050.
euronuclear.org/info/encyclope…
euronuclear.org/info/encyclope…
An additional point have to be noted: the availability of more research papers on a given scenario (e.g., increasing nuclear power) does not imply that the scenario is preferred. It is only more likely to happen with current country policies and forecasts.
Therefore, by 2050 we can minimize the number of nuclear reactors or multiply it to unprecedented numbers.
Since the IPCC is an objective body worldwide accepted, let's see what it says about nuclear power in its latest report:
ipcc.ch/sr15/
Since the IPCC is an objective body worldwide accepted, let's see what it says about nuclear power in its latest report:
ipcc.ch/sr15/
✅Advantages: low GHG emissions, low health risks per kW·h, baseload power generation, and low land requirement.
Interested parties take advantage of this objectivity and circulate biased information to the public, spreading a false idea of IPCC's full support for nuclear power.
Interested parties take advantage of this objectivity and circulate biased information to the public, spreading a false idea of IPCC's full support for nuclear power.
But the IPCC also points to disadvantages of nuclear energy. They are included here literally, without own comments:
❌ Historically, speed of scaling has been high in many nations. However, such rates are not achieved anymore. Current time-lag is observed to be 10-19 years.
❌ Historically, speed of scaling has been high in many nations. However, such rates are not achieved anymore. Current time-lag is observed to be 10-19 years.
❌ Costs of nuclear power have increased in several developed countries. “Learning by doing” often failed to compensate for this trend due to the absence of standarization. What are and have been the costs of nuclear power is still debated in the literature.
❌ Uranium mining and milling have negative effects comparable to those of coal. Hence, replacing coal combustion by nuclear power would be neutral in that aspect.
❌ There are also safety and waste concerns from uranium mining and milling.
❌ There are also safety and waste concerns from uranium mining and milling.
❌ Increasing temperatures will decrease the thermal efficiency of nuclear power generation technologies. Fossil, biomass, and solar power will also be affected.
❌ Nuclear power generation requires water for cooling. That can lead to water stress, one of the biggest risks worldwide in the next decade (World Economic Forum).
weforum.org/reports/the-gl…
weforum.org/reports/the-gl…
❌ A non-negligible risk for accidents in nuclear power plants remains.
❌ Radioactive waste treatment facilities also pose a risk for accidents.
❌ Radioactive waste treatment facilities also pose a risk for accidents.
❌ Continued use of nuclear power poses a constant risk of proliferation.
▶️ Some studies have shown an increase in childhood leukaemia in populations living within 5 km from a nuclear power plants. However, the IPCC warns that no direct causes have been established. There is low evidence and little scientific agreement on this issue. ‼️
❌ The long-term storage of nuclear waste is a politically fraught subject, with no lare-scale long-term storage operational worldwide
❌ Nuclear waste and abandoned reactors imply a "legacy cost", that is, a historical burden or inherited costs that are transferred to future generations not responsible for the problem.
❌ Reprocessing of spent fuel can significantly reduce the volume of high-level waste, but it is not economically competitive with uranium costs below 425 $/kg. Current uranium reserves under 260 $/kg will last 130 years.
ipcc.ch/site/assets/up…
ipcc.ch/site/assets/up…
❌ If spent fuel reprocessing technologies were generalized, it would further raise proliferation concerns. The advantages and disadvantages of alternative reprocessing technologies are still under investigation.
The IPCC report also evaluates the available technologies that could replace coal. In 2018, coal accounted for 28% of the global energy consumption (BP Statistical Review). It also presents the highest CO₂ emissions, so phasing it out before 2050 is essential.
Solar, wind and hydropower generation technologies stand out above the rest. Biomass/bioenergy with CCS are valued well below due to certain unresolved issues. Finally, nuclear power is the only one with an overall negative value, with more disadvantages than advantages.
In a previous report, the IPCC showed that limiting biomass or carbon capture would be 10-20 times more expensive (in mitigation costs) than phasing out nuclear power. Nevertheless, lifetime extension of existing plants was seen as a more interesting approach.
In summary, the IPCC concludes that nuclear energy has “negative environmental effects and has mixed effects for human health when replacing fossil fuels”.
One last tweet to include all the texts cited and the references therein.
If you got here, kudos! Is this any similar to what you had been told?
