How to face "nuclear power" as seen in FinlandMarch 3 at 20:19

"There are countries to look at in their efforts to ensure nuclear safety."

As experts continued to cover the investigation of the Fukushima Daiichi nuclear accident, experts named a small country with a population of about 550.<> million.
Scandinavia and Finland.
Ahead of the United States and France, known as "nuclear powers," construction of a new type of reactor "EPR" has also begun.

How has this country, known for Santa Claus and the Northern Lights, dealt with nuclear power? We approached it with on-site coverage and interviews with key people.

(Project Center Yoichiro Sasakawa)

12 years after the accident at the Fukushima Daiichi Nuclear Power Plant, the tide surrounding nuclear power has changed

The accident at TEPCO's Fukushima Daiichi Nuclear Power Plant occurred 12 years ago.

When I heard the news that Unit 1 had exploded, I was working for NHK Sendai Broadcasting Station and was in charge of emergency reporting immediately after the Great East Japan Earthquake in the city.

"Evacuate indoors until you know the situation at the Fukushima Daiichi Nuclear Power Plant,"

I remember the impatience and anxiety I felt in Sendai, less than 100 km from the nuclear power plant.

After the accident at Fukushima Daiichi accelerated the world's efforts to reduce dependence on nuclear power.

However, an increasing number of countries are now reevaluating the role of nuclear power against the backdrop of the energy crisis and global warming countermeasures triggered by the situation in Ukraine.

Even Japan, the tide surrounding nuclear power changed last year. In August, Prime Minister Kishida announced that in addition to "restarting" and "extending the operation period," Japan would consider "developing and constructing next-generation nuclear reactors" for the first time since the accident.

Looking at the world, each country is constructing nuclear power plants called "new reactors" ahead of the Japan.

One of them is a nuclear reactor called the EPR (European Pressurized Water Reactor). Construction first began in Finland in 8.

What kind of nuclear power plant is it?
Also, how does the public perceive nuclear power?

I headed to the interview.

"Nuclear power plant advertisement" I saw at Helsinki airport

Helsinki Airport, the gateway to Finland. When you walk around the airport, you will see a prominent advertisement.

"Our nuclear power plants = our nuclear power plant" I was surprised by the "nuclear power plant advertisement"

at the doorstep of the country.

It's not just nuclear power. There is also a thermal power plant 3km from Helsinki Central Station.

I felt that "energy" has become a familiar topic in everyday scenes in this country.

In Helsinki, where trams come and go around the city and public buses run partly on electricity, we asked about his thoughts on nuclear power and the Fukushima nuclear power plant accident.

"We are well aware of what happened in Fukushima, but Japan is also geographically at risk of earthquakes. I want to believe that nuclear power plants in Finland are safe. Because it has very stable ground. (Female, 60s)" "

I am neutral about nuclear power, but I think that nuclear power plants in Finland are quite safe, but on the other hand, there is the problem of radioactive waste. That's an important point. (Male, 70s)"

What surprised me was the high level of basic knowledge about nuclear power. Everyone I spoke to knew about the "name" of nuclear power plants in Japan, the "location area" and even the "number of years of operation" as a matter of course.

Finland uses nuclear power to meet more than one-third of the country's electricity needs. Currently, four nuclear power plants that began operation in the 3s and 1s are in operation.

According to opinion polls, after the Chernobyl (Chornobyl) nuclear accident in 1986, there were many deniers of nuclear power for more than 10 years, but in the latter half of the 1990s, the positive side reversed.

This trend continued even after the accident at the Fukushima Daiichi Nuclear Power Plant.

Over the past few years, the proportion of positive people has increased further, with the latest poll showing that the number of positive voters has reached 60%, while the number of naysayers has remained at around 10%.

What is the safety system that works with the latest nuclear reactor and EPR automation?

From Helsinki, it is about 220km in a straight line to the west. Head to the new reactor "EPR" built on the island of Olkiluot.

This distance is actually about the same as the distance from Tokyo to the Fukushima Daiichi Nuclear Power Plant.

How is the design of EPR different from conventional nuclear power plants? When I visited the visitor center, I saw a detailed model of the inside of the nuclear power plant.

The biggest feature of EPR is its safety design.

A containment vessel that can withstand aircraft falls.

Furthermore, on the premise that the "meltdown" nuclear fuel would break through the reactor, a "core catcher" was installed as a corresponding device.

Let's take a look at how it works.

In EPR, the melted nuclear fuel from the bottom of the reactor is guided through a path with high heat resistance in the green part and into a room beyond.

After that, a large amount of poured water circulates. Cooling nuclear fuel from above and below.

As a result, the aim is to suppress the pressure rise in the containment vessel and confine radioactive materials inside.

The biggest feature of these systems is that they are designed to operate automatically using natural phenomena such as gravity, without the need for human judgment or electricity.

It is made on the premise that when an accident occurs, a situation that people such as drivers may not be able to respond.

Strict Finnish nuclear regulations

This core catcher is the first facility to be adopted at a nuclear power plant in the world. Therefore, regulatory bodies must examine whether sufficient performance is ensured.

We visited the department in charge of nuclear safety at the STUK (Center for Radiation and Nuclear Safety), which is responsible for regulating nuclear power plants in Finland.

This time, I was able to interview Ellen Heetenkibi, who is in charge of reactor and safety systems.

In fact, this "core catcher" is said to be a necessary "performance" for a new nuclear power plant to be built in Finland.

STUK Ellen Hitenkibi:
"Even before the Fukushima Daiichi accident, Finland has made it a requirement to cool and stabilize the hot nuclear fuel that melted from the reactors to minimize the release of radioactive materials outdoors. In that respect, the core catcher works automatically, so there is no risk of human error and it is considered a better solution."

A situation in which nuclear fuel melts. In the field of nuclear power, this is called a "severe accident."

Even before the Fukushima Daiichi nuclear accident, the way they prepared for this situation was very different from Japan.

Even if the Three Mile Island nuclear power plant accident (1979, USA) and the Chernobyl (Chorneville) nuclear power plant accident (1986, former Soviet Union) occurred, severe accident countermeasures were left to the voluntary measures of electric power companies in Japan, and were not subject to examination by regulatory bodies.

In Finland, on the other hand, in response to the Three Mile Island nuclear power plant accident, regulatory agencies issued regulatory requirements for severe accidents three years later.

STUK Ellen Heetenkibi:
"The first regulatory requirements for new nuclear power plants were issued in 1982. After the Chernobyl accident in 1986, the debate called for all nuclear power plants in Finland, that is, those that were already in operation, to develop severe accident management strategies. Therefore, all nuclear power plants are required to develop severe accident management strategies, which are reviewed by regulatory bodies."

A regulatory standard developed by STUK called "YVL". It also stipulated a regulation of the total amount of radioactive material released in the event of an accident.

STUK Ellen Hitenkibi:
"Finnish nuclear legislation stipulates that even before the Fukushima Daiichi accident, radioactive materials released from the plant "must not cause acute health hazards or long-term restrictions on land or water." Therefore, it is limited to 137 terabecquerels or less in terms of cesium-100. In other words, the 137 terabecquerels regulation for cesium-100 is based on the philosophy that there is no need to evacuate people outside a 5km radius of a nuclear power plant. In addition, there should be no acute health hazards to residents."

The law was already in force in 1991. It was five years after the Chornobyl nuclear accident.

I was struck by the use of the word "philosophy," which is a fundamental principle for nuclear safety regulations.

In addition, it demanded that the probability of a large release of radioactive materials be kept low.

When asked about regulations on the "frequency of large-scale releases" (= the probability of occurrence of events leading to large-scale releases of radioactive substances), what is required for newly constructed nuclear power plants is to limit the risk of "frequency of large-scale releases" to less than 200/1 million per year.

This is twice as strict as many countries stipulate less than 100/1 million per year.

既存の原発にも常に“改善“を要求

この要求は新たに建設される原発にだけ求めているわけではない。

すでに稼働しているいわば“古い”原発に対しても、こうした基準を達成する努力を継続的に行うよう求めている。

フィンランド南部にあるロヴィーサ原発。福島第一原発と同じく1970年代に運転を開始した。

この原発は旧ソビエトの設計。STUKは放射性物質を閉じ込めるための格納容器に脆弱性があると指摘した。

しかし、巨大な構造物である格納容器の改修は容易ではない。

それでも電力会社は、大規模な改修を決断。

数十億円を投じ、2003年にかけて工事を行った。

「格納容器の性能が十分でなければ、溶け落ちた核燃料を原子炉にとどめることができるようにすればいい」

そう考えた技術者たちは新たな設計に着手した。

そして生み出したのが、IVR（In Vessel Retention＝炉心溶融デブリ炉内保持）と呼ばれる設計。

原子炉の下半分をワインクーラーのように水に浸し、冷却。核燃料が溶けても原子炉から格納容器に漏らさない設計に変えた。

この斬新な設計はどこかの原発を参考にしたのかと尋ねると、「自分たちの発電所が世界で最初に取り入れた設計です。私たちはそれをとても誇りに思っています。その後、アメリカで開発された新しい原子炉（AP1000）にもこの設計が取り入れられました」

こうした取り組みの元になる安全への基本的な考え方も語った。

Mika Harty, Fortum:
"For us, an IVR is like a car airbag: if we can inject water into the reactor in the event of an accident, we can prevent core meltdown, and that is our primary goal. However, if that fails, the molten nuclear fuel is kept in the reactor. That's why we set up a backup, or 'car airbag.'"

The Lovisa Nuclear Power Plant has continued to take measures every year since the introduction of IVR, and the probability of an accident has decreased to 20/30 in the past 1 years.

But regulator STUK says it doesn't believe the current measures are enough.

STUK Ellen Hitenkibi:
"In Finland, all nuclear power plants are being continuously improved, and if there is a technology that can make it safer, it should be implemented. We will continuously update and improve safety. That is the basic principle of our use of nuclear power."

In October last year, TEPCO signed an information exchange agreement with Fortum on the nuclear field.

Based on Fortum's knowledge gained from overseas, such as the utilization of risk information in the maintenance and management of facilities and methods for assessing deterioration over time, Fortum intends to further improve the safety and reliability of nuclear power plants.

Residents living near the nuclear power plant

What do residents think about these regulatory bodies and power companies?

About 10 km from the Olkiluoto nuclear power plant, I was able to talk to Timo Ante, a farmer who grows wheat and other crops.

Timo was also interested in the accident at the Fukushima Daiichi Nuclear Power Plant and gathered information himself.

Timo Ante:
"At the Fukushima Daiichi Nuclear Power Plant, we were not prepared for a tsunami. There was not enough backup power, it was flooded, and the reactor could not be cooled due to the lack of power supply."

If radioactive materials are released from a nearby nuclear power plant, agriculture will be greatly affected. For this reason, Timo cares about nuclear power plants on a daily basis and gathers information.

On the day of his visit, the start of trial operation at the Olkiluoto Nuclear Power Plant was approaching, so Timo checked the information updated on the power company's website.

Timo Ante:
"The power companies are very open to providing information for us citizens, and of course there are those who are against nuclear power. But that's normal in a normal free society, people have to have their own opinions, and that's okay."

In fact, EPR continues to have construction problems. Construction began in 2005 and was scheduled to be completed in 2009, but problems followed.

The construction cost is also significantly higher than originally planned.

After 18 years of construction, the company is currently in test operation with the aim of finally starting commercial operation this year.

In fact, we were scheduled to participate in a media tour where we could cover the inside of EPR, but due to unexpected troubles, the media tour was postponed.

We got a glimpse of the difficulty of building a new nuclear reactor.

Message from Key Figures in Nuclear Regulation

There was a person I really wanted to talk to during this interview in Finland. Jukka Laksonen was once the head of the regulatory body STUK for many years.

After the accident at the Fukushima Daiichi Nuclear Power Plant, he was invited to Japan and gave a lecture on the concept of safety regulations, and is one of the world's most well-known key figures in the field of nuclear safety.

Former
STUK Director Jukka Laksonen: "Our philosophy is to make safety as high as possible. Of course, we cannot guarantee absolute safety. But there are some weaknesses, which must be corrected. Consider not only events that may arise from inside the power plant, but also earthquakes, major fires, and other external disasters. And that requirement is always in need of change. For example, after a plane hit the World Trade Center building in New York on September 9, we decided to set regulations that would allow us to protect nuclear power plants even if they hit the planned power plant "Olkiluoto 11."

Laaksonen also headed the Western European Association of Nuclear Regulators (WENRA), a group of regulatory bodies from 18 Western European countries.

At that time, in 2009, Japan set safety targets common to each country for new nuclear power plants.

It reads, "Emergency evacuation is not necessary except for those who live near the nuclear power plant to avoid permanent relocation of residents." In other words, they are calling for safety design that does not cause long-term evacuations of residents as in the case of the Chornobyl (Chernobyl) nuclear accident and the Fukushima Daiichi nuclear power plant accident.

Once an accident occurs, it is a nuclear accident that causes enormous damage.

This document calls into question the country's readiness to use nuclear power.

Former
STUK Director Jukka Laksonen: "After the Chernobyl accident, the importance of a safety culture has been emphasized. Even in the event of a meltdown, we want people to continue their lives. Between the heads of regulatory bodies in each country, there is no disagreement. There is an atmosphere and attitude that we must work together to improve the safety of nuclear power plants. The possibility of similar accidents is excluded. But we don't know what's going to happen in the future."

"There is no absolute safety" and "You never know what will happen in the future"

are simple, but I felt that the words of the former head of the regulatory body conveyed the most important ideas in dealing with nuclear power plants.

After the interview

Until this interview, I had no image of Finland as an "advanced nuclear power country."

Through on-site interviews, I felt the strong will of regulatory agencies and electric power companies that "unless we take the stance of continuously improving safety based on the premise that there is no goal, we will not be able to gain the public's approval."

After the accident at the Fukushima Daiichi Nuclear Power Plant, what kind of determination will Japan have to face nuclear power plants? There are many foreign initiatives that should be referenced.

Project Center
Yoichiro Sasakawa Japan
worked
at the Sendai Bureau when the Great East Japan Earthquake occurred, Japan after working in the Social Program Department, he now belongs