Task: Translation
Input (Japanese): カナダで設計されたCANDU炉は、燃料の効率性とダウンタイムの短さにおいて原子炉の中で最も有力な方法の一つだ。
Output (English): CANDU reactors, which are designed in Canada, are one of the most advantageous forms of nuclear reactors due to their fuel efficiency and low amount of down-time.