3 ms·

News articles to this effect have been popping up occasionally for the past 20 years at least. So the economics don't seem to stack up. At least not yet; but if

• JeremyNT 18d ago
  They really are being built and used commercially. Probably incentives play a part in this, but their numbers are slowly increasing, so it's not totally vaporware (of course we don't need new articles every ~6 month talking about how amazing this technique is) [0] [0] https://en.wikipedia.org/wiki/Rotor_ship#Modern_vessels https://en.wikipedia.org/wiki/Rotor_ship#Modern_vessels
• nomel 18d ago
  Some of these sails claim 10% fuel reduction, which is ~5% operational cost, or ~150k per trip to spend on some tubes of metal or sheets of cloth.
  • nomel 17d ago
    Sorry, typo, and unclear. I meant to say fuel is ~50% operational cost.
  • ricree 17d ago
    I've seen a few articles about Norsepower (mentioned in the top article) validating the shipboard measurement equipment meant to confirm how much is actively being saved by their sails. I haven't seen any hard numbers on what the actual savings are, but they've had at least one ship (Chinook Oldendorff) with sails since at least 2024. So hopefully the public will get some concrete numbers on how much is saved. Given the increasing number of companies that are mentioned as upcoming partners for actual installations, it might be that they've finally been able to convince shippers that wind power is viable for cost savings.
  • askvictor 17d ago
    Is that 10% best case or average case? Also, what's the capex on the the sails, and what's the additional opex (training, maintenance)? Not trying to pooh-pooh the idea, but as said, I've seen articles like this regularly for decades, and it hasn't become the norm, so I'd figure there's a reason for that.