報告書番号

Y98019

タイトル（和文）

わが国における原子力発電コスト構造の将来展望

タイトル（英文）

Future Trends of Nuclear Power Generation Cost Structure in Japan to 2010

概要 （図表や脚注は「報告書全文」に掲載しております）

財務諸表に基づいて算出した原子力発電コストの過去の実績を踏まえて、2010年度までの原子力発電の費用構造の変化について評価した。その結果、2010年度まで新規の原子力発電所が建設されない場合には、発電コストは断続的に低下するのに対し、新規の発電所建設がある場合には、短期的に発電コストが上昇する結果となる。また、原子力発電コスト低減の可能性として、既存プラントの修繕費低減は新設炉の建設費の低減と同様な効果を有する。つまり、今後、原子力発電所の新規建設基数が少数に限られる一方で、運転中の発電所の高経年化が進む状況を考慮すると、建設費の低減はもちろんのこと、修繕費の低減や設備利用率の向上により努力を向けるべきである。他方、燃料サイクル費とりわけ再処理費、廃棄物処理費は、今後の不確実性が大きく、上記のコスト低減を上回るほどのコスト上昇をもたらす可能性があり、その抑制に全力を挙げる必要がある。

概要 （英文）

This paper estimates future trends of nuclear power generation cost in Japan to the year 2010 based on annual corporate financial statements published by the nine Japanese electric power utility companies. Each item of nuclear power generation cost is estimated and extrapolated under two scenarios; one without any new construction (Case 0), and the other with additions of all the planned reactors commenced (Case A). The results are summarized as follows. (1) The nuclear power generation cost will decrease continuously from 7.23 yen/kWh in 1996 to 5.10 yen/kWh in 2010 for Case 0, while for Case A the generation cost will stop decreasing in 2002 and get hiked slightly as each new unit commences after 2002 and reach 6.24 yen/kWh in 2010. The difference (1.14 yen/kWh) can be explained primarily by the depreciation cost of new power plants. The power generation cost of new nuclear plants only in 2010 is estimated to be 9.33 yen/kWh. (2) The shares of both O&M cost and fuel cycle cost in the total generation cost will increase continuously, from 28% and 24% in 1996 to 38% and 35% in 2010 in Case A, and to 48% and 43% in 2010 in Case 0, respectively. (3) In Case A, 20% reduction of construction cost or repair cost shows almost similar magnitude of impacts to the total generation cost in 2010. While the reduction of construction cost is usually believed as most effective to reduce overall generation cost of nuclear, its influences in Case A at 4.3% reduction in 2010 is almost equal to that of repair cost. The generation cost becomes 4.4% lower in 2010 with a 20% reduction of repair cost in Case A and 6.4% lower in Case 0. (4) The improvement of the overall utilization factor up to 87.5% provides a cost reduction equivalent to 20% reduction of construction cost or repair cost. (5) The fuel cycle back-end has significant uncertainties in the future. In particular, the reprocessing cost is critical as its share in total generation cost will steadily increase from 7% in 1996 to 13% in 2010 (0.7 yen/kWh).

報告者

キーワード