Nuclear reactors in seismic areas. Is installation in Greece feasible?

Import

The debate on nuclear energy regularly comes to the fore, especially in times of energy crises and heightened environmental concerns. In the case of Greece, the idea of installing nuclear reactors comes up against a major factor: the country’s seismic activity. This article examines in depth the challenges, risks and technological solutions associated with installing nuclear reactors in seismically active regions such as Greece.

Seismic activity in Greece

Greece is located in one of the most seismically active regions of Europe, as it is located on the convergence boundary between the African and Eurasian tectonic plates. According to data from the Geodynamic Institute of the National Observatory of Athens:

• The country experiences more than 3,000 earthquakes annually.
• About 50 of them have a magnitude greater than 4 on the Richter scale.
• Approximately 1-2 earthquakes of magnitude greater than 5.5 on the Richter scale are recorded each year.

This intense seismic activity raises legitimate concerns about the safety of critical infrastructure, such as nuclear reactors.

Nuclear reactors and seismic activity: International examples

The example of Japan

Japan is the most prominent example of a country with high seismic activity that has a significant number of nuclear reactors. Before the Fukushima accident in 2011, the country had 54 reactors generating about 30% of electricity.

The Fukushima nuclear accident was caused by a combination of:

1. A powerful earthquake measuring 9.0 on the Richter scale
2. The subsequent tsunami of over 14 meters high
3. Inadequate preparation for a disaster of this scale

It is worth noting that the reactors withstood the earthquake, but the cooling systems failed due to the tsunami, leading to the core meltdown.

Other international examples

• USA (California): The Diablo Canyon nuclear power plant operates in an area with significant seismic activity, having been designed to withstand earthquakes of up to 7.5 on the Richter scale.
• Taiwan: It has three nuclear power plants despite the high seismicity of the region.
• Turkey: It has begun construction of its first nuclear power plant in Akkuyu, despite the country's seismic risk.

Modern earthquake protection technologies

Modern nuclear reactors incorporate advanced earthquake protection technologies:

1. Seismic base insulation

This is a technology that allows the reactor to “float” on its foundations during an earthquake, absorbing vibrations. Specifically:

• Elastomeric bearings with lead core
• Friction pendulum systems
• Hydraulic dampers

2. Reinforced structures

• Reinforced concrete buildings up to 2 meters thick
• Double reactor casing
• Reinforced container shielding

3. Passive safety systems

Third and fourth generation reactors have systems that operate without an external power supply, thus avoiding the Fukushima scenario:

• Cooling systems operating with natural circulation
• Passive emergency core cooling systems
• Automatic extinguishing systems

Is it possible to install in Greece?

Technical feasibility

From a purely technical point of view, the installation of modern nuclear reactors in Greece could be feasible with the appropriate specifications:

1. Choosing a suitable location: Areas with lower seismic risk, such as parts of Western Macedonia
2. Use of advanced reactors: Fourth generation reactors with enhanced passive safety systems
3. Overdesign: Design with safety margins for earthquakes of greater intensity than expected

Economic sustainability

However, the cost of building a nuclear power plant with the necessary earthquake-resistant specifications for Greece would be extremely high:

• Estimated construction cost: 10-15 billion euros for a 1GW reactor
• Additional cost 30-40% for high level anti-seismic specifications
• Long payback period (25-30 years)

Alternative solutions for Greece

To meet the country's energy needs, there are alternatives with a better cost-benefit ratio:

• Renewable energy sources: Greece has abundant solar and wind potential
• Small Modular Reactors (SMRs): Smaller, cheaper and easier to install and move
• Interconnection with neighboring countries: Importing nuclear energy from countries like Bulgaria

Legal and social framework

Beyond technical and financial issues, there are significant legal and social obstacles:

• The Greek Constitution does not explicitly prohibit nuclear energy
• However, there is strong social opposition due to:
  • Fear of seismic disasters
  • Environmental concerns
  • The memory of accidents like Chernobyl and Fukushima

Polls show that over 751% of Greeks are opposed to the construction of nuclear power plants in the country.

Conclusions

In summary, the installation of nuclear reactors in Greece is technically feasible with modern technology, but remains a challenge from an economic, social and political perspective:

1. Technically: Modern reactors have advanced earthquake protection systems
2. Finance: High construction and maintenance costs make other solutions more attractive
3. Social: There is significant resistance from public opinion
4. Strategic: Energy diversification with an emphasis on RES seems more appropriate for the country's conditions

Although technology now allows the safe operation of nuclear reactors even in seismic areas, the question for Greece is more economic and social than technical. Weighing the costs and benefits and examining alternative solutions is essential before making any decision about the country's energy future.

Greek Sources

Wikipedia (Greek):

• “Nuclear energy in Greece”
  • https://el.wikipedia.org/wiki/Nuclear_energy_in_Greece
• "Reactor"
  • https://el.wikipedia.org/wiki/Nuclear_reactor
• "Nuclear energy"
  • https://el.wikipedia.org/wiki/Nuclear_energy

News Sources:

• LiFO: “Nuclear Energy: 413 Reactors Worldwide – Rebirth or Abolition after Fukushima?”
  • https://www.lifo.gr/now/perivallon/pyriniki-energeia-413-antidrastires-se-oli-ti-gi-anagennisi-i-katargisi-meta-tin

Seismological Sources:

• Ecozen: “The most seismic areas of Greece and the planet on an online map”
  • https://ecozen.gr/2018/12/pio-sismogenis-perioches-tis-elladas-ke-tou-planiti-se-enan-online-charti/
• Travelstyle: “The most seismic countries in the world: Greece in the top 10!”
  • https://www.travelstyle.gr/oi-pio-seismogenhs-xwres-ston-kosmo-h-ellada/

Academic Sources:

• University of Athens – Department of Chemistry: “Nuclear Energy” (Chapter 6)
  • https://eclass.uoa.gr/modules/document/file.php/CHEM199/Βιβλίο%20Ραδιοχημείας/KEFALAIO-6_PYRHNIKH-ENERGEIA.pdf

European Sources:

• European Union: “Indicative nuclear program”
  • http://publications.europa.eu/resource/uriserv/l27072.ELL

International Sources

World Nuclear Association:

• “Nuclear Power Plants and Earthquakes”
  • https://world-nuclear.org/information-library/safety-and-security/safety-of-plants/nuclear-power-plants-and-earthquakes
• “Earthquakes and Seismic Protection for Japanese Nuclear Power Plants”
  • https://world-nuclear.org/information-library/safety-and-security/safety-of-plants/appendices/earthquakes-and-seismic-protection-for-japanese-1.aspx
• “Fukushima Daiichi Accident”
  • https://world-nuclear.org/information-library/safety-and-security/safety-of-plants/fukushima-daiichi-accident

International Atomic Energy Agency (IAEA):

• “No Safety Concern at Nuclear Power Plants After Powerful Earthquake, Japan Informs IAEA”
  • https://www.iaea.org/newscenter/pressreleases/no-safety-concern-at-nuclear-power-plants-after-powerful-earthquake-japan-informs-iaea

Academic & Research Sources:

• NCBI Bookshelf: “Great East Japan Earthquake and Tsunami and Impacts on Japanese Nuclear Plants”
  • https://www.ncbi.nlm.nih.gov/books/NBK253933/
• IntechOpen: “Issues of the Seismic Safety of Nuclear Power Plants”
  • https://www.intechopen.com/chapters/52742
• Stanford University: “Safeguards for Nuclear Power Plants in Earthquake-Prone Areas”
  • http://large.stanford.edu/courses/2013/ph241/yapa1/

Sasakawa Peace Foundation:

• “The Problems of Nuclear Energy Use by Japan Raised Again by the Noto Peninsula Earthquake”
  • https://www.spf.org/iina/en/articles/yuki_kobayashi_07.html

Wikipedia (English):

• "Fukushima nuclear accident"
  • https://en.wikipedia.org/wiki/Fukushima_nuclear_accident
• “Nuclear power in Japan”
  • https://en.wikipedia.org/wiki/Nuclear_power_in_Japan

Key Points from the Sources

Greek Context: Although Greece has established the Hellenic Atomic Energy Commission, the country's policy so far is against any nuclear power generation program. Nuclear power in Greece – Wikipedia.

Seismicity of Greece: Greece is among the most earthquake-affected countries in the world The most seismic areas of Greece and the planet on an online map, with Greece (mainly western and southern) being one of the most seismically active regions The most seismic countries in the world: Greece in the top 10! You will be speechless with its position.

Seismic Safety of Nuclear Facilities: Nuclear facilities are designed so that earthquakes and other external events do not compromise the safety of the plant. Earthquakes and Seismic Protection for Japanese Nuclear Power Plants – World Nuclear Association, while Japanese nuclear power plants are designed to withstand specified seismic intensities Nuclear Power Plants and Earthquakes – World Nuclear Association.

Lessons from Fukushima: The first Fukushima reactors were built in the 1960s, when scientific understanding of the risks from natural external events was very limited. Great East Japan Earthquake and Tsunami and Impacts on Japanese Nuclear Plants – Lessons Learned from the Fukushima Nuclear Accident for Improving Safety of US Nuclear Plants – NCBI Bookshelf.