コーセル orders surge 4x as AI power trade takes off

Cosel's surprise earnings on September 18 were the trigger for a broader re-rating of Japan's power supply and power electronics names. The stock opened the afternoon session with buy orders only, volume topped ten times its normal level, and the buying continued after the holiday weekend; by the September 25 close of 1,474 yen it was up about 12% from before the results. The numbers behind the move were not just headline growth: the company's semiconductor equipment order intake swelled to roughly 3.5 billion yen from about 800 million yen a year earlier, total orders reached 13 billion yen (2.5x the prior year), and the backlog climbed to 17.9 billion yen, up 94%.

The story ties into a wider shift in how AI infrastructure is viewed. The IEA expects global data center power consumption to nearly double, from 485TWh in 2025 to 950TWh in 2030, while a single GPU's draw has gone from about 400W several generations ago to over 1,000W in the latest generation, and per-rack power is seen rising from about 130kW to 600kW. Nvidia has said it plans full-scale adoption in 2027 of an 800V DC supply architecture, with Rohm and Renesas named among its partners. Fuji Keizai projects the global power semiconductor market nearly doubling from about 3.8 trillion yen in 2025 to about 7.3 trillion yen in 2035.

For all the enthusiasm, the body flags the risks. Cosel itself says the first-quarter orders included customers placing orders early and expects the pace to calm from the second quarter, and its fortunes remain tied to the memory capital spending cycle, component prices, and its relationship with top shareholder LITE-ON. More broadly, after July's slump in AI-related shares, the market appears to be moving from buying the theme as a whole to picking stocks on actual earnings — which makes execution, not narrative, the thing to watch.