発電のコスト―やはり原発は高くつく

October 27, 2011
--The Asahi Shimbun, Oct. 27
EDITORIAL: New cost estimates argue for changing nuclear power policy
発電のコスト―やはり原発は高くつく

New government estimates that factor in the cost of the disaster at the Fukushima No. 1 nuclear power plant show that nuclear power generation is actually a relatively expensive way to produce electricity.
　原子力発電にかかる費用は、高かった。

The damage from the accident is so vast and wide-ranging that a final figure is not yet available.
　福島第一原発事故による損害はあまりに大きく、まだ全体を計算できない。

However, the Cabinet Office’s Japan Atomic Energy Commission has come up with a broad idea of how much the disaster will raise the cost of nuclear power generation.
だが、今わかっている範囲で、内閣府の原子力委員会が発電費用への上乗せがどうなるか試算した。

The additional cost due to the accident could be as high as 1.2 yen per kilowatt-hour of electricity, according to the commission’s estimate.
事故のコストは電気１キロワット時あたり最大で１．２円になった。

A core meltdown occurred at three of the six reactors at the disabled plant.
　今回、原子炉３基で炉心溶融が起きた。

Based on the total number of years that Japan's 50-odd nuclear power plants have been in operation, divided by the number of crippled reactors, it can be estimated that an accident of this scale occurs once every 500 years per reactor.
日本にある約５０基の原発の運転年数を足し、福島の事故炉の数で割ると、この規模の事故は平均して「原発１基あたりで、ほぼ５００年に１度発生する」確率になる。

This estimation was used to calculate the cost increase.
その計算から割り出した。

If the cost of the accident is factored in, the overall tab of nuclear power generation comes to 6.8 yen per kilowatt-hour, compared with 5.7 yen for thermal power generation using coal as fuel or 6.2 yen for generating electricity by burning liquefied natural gas.
　この事故コストを加えると、原子力発電のコストは１キロワット時あたり６．８円になる。石炭火力の５．７円や、液化天然ガス火力の６．２円を上回る。

The new cost estimates are ball park figures and don’t take account the money needed for the massive-scale decontamination that has yet to be undertaken.
　いずれも大ざっぱな計算であり、今後は膨大な除染もある。

Another important cost factor concerns the unsolved issue of the final disposal of radioactive waste being produced by nuclear power plants across the nation.
また、全国の原発から出る放射性廃棄物の最終処分も残り、

Clearly, the cost of atomic power generation will be much higher than traditional estimates.
さらに割高になるのは確実だ。

Nuclear power generation has long been touted as “a cheap and safe way to produce a large amount of electricity.”
　これまで「安く、安全に大量の発電をする」と宣伝されてきた原発だが、

But the Fukushima disaster has disproved not only the claim of its safety but also that of its economic advantage.
事故の危なさに加え経済面の優位も崩れた。

The Atomic Energy Commission has produced another important cost estimate.
　原子力委はもう一つの計算もした。

Japan has adopted the nuclear fuel reprocessing approach, which involves extracting plutonium from spent nuclear fuel for recycling as fuel.
日本は、使用済み燃料を再処理してプルトニウムを取りだし、それを燃やす「再処理路線」をとる。

This process costs 2 yen per kilowatt-hour.
これは１キロワット時あたり２円かかる。

In contrast, the direct disposal approach, which involves burning uranium just once and disposing of the radioactive waste produced in the process, costs 1 yen, half of the cost of reprocessing, according to the commission.
　一方、ウラン燃料を１回だけ燃やして、廃棄物は捨てる「直接処分」の費用は半分の１円で済むことがわかった。

This is a big difference.
　この差は大きい。

The total cost of nuclear power generation would be 5.8 yen if the current reprocessing approach is replaced by the direct disposal method.
もし、直接処分に変えれば、発電コストは１円安い５．８円になる。

The Atomic Energy Commission made the same cost comparison seven years ago, and the results were roughly the same.
　原子力委は７年前にもこの比較をした。結果は今回とほぼ同じだったが、

But it decided against proposing to drop the policy of fuel reprocessing, citing the huge costs that would result from such a major policy shift.
再処理の路線を変えなかった。理由は「政策変更コスト」だった。

There is the argument that changing the policy would negate past investment and require new research while straining the central government’s relations with the local governments of the areas where nuclear power plants are located.
「過去の投資が無駄になり、新たな研究も必要だ。立地自治体との関係も悪くなる」という論法だ。

This argument doesn’t hold water any more.
　もう同じ手は使えない。

In the wake of the catastrophic accident, there is strong public distrust toward nuclear power.
事故を経験した今は、国民の原発への不信が大きい。

It is almost impossible to win public support for the reprocessing approach, which can only make a small saving of uranium at a high cost.
高い費用をかけて「ウラン燃料を少し節約する」再処理に説得力はない。

The two cost estimates are hard numbers that throw into sharp relief the grim reality of nuclear power generation in Japan.
　二つのコスト計算は、数字で日本の原子力の現状を浮かび上がらせた。

It is clearly time for the govrnment to change its nuclear power policy, which has been in place since the end of World War II.
　戦後一度も大きく変えることのなかった原子力政策を変更するときだ。

The government’s Energy and Environment Council should lead debate on the issue.
政府のエネルギー・環境会議の責任は大きい。

As such, it bears a heavy responsibility.
Japan must face up to the fact it needs to pursue a future without nuclear power.
　原発をなくす道に向き合うしかない。

At the same time, we feel debate is also needed on scrapping nuclear fuel reprocessing, the necessity of which has been called into question.
同時に、必要性が疑問になった核燃料再処理から撤退する議論も始めよう。

The time has come for the government to grapple with the cost of changing its nuclear power policy.
政府は今度こそ、政策変更コストに取り組まなくてはいけない。
　その準備を始めるときだ。