And even in some prototype bus, the Gyrobus, in the 50’s that used an electrically charged flywheel that was also (to some degree) regeneratively recharged when breaking:

Rather than carrying an internal combustion engine or batteries, or connecting to overhead powerlines, a gyrobus carries a large flywheel that is spun at up to 3,000 RPM by a “squirrel cage” motor.[1] Power for charging the flywheel was sourced by means of three booms mounted on the vehicle’s roof, which contacted charging points located as required or where appropriate (at passenger stops en route, or at terminals, for instance). To obtain tractive power, capacitors would excite the flywheel’s charging motor so that it became a generator, in this way transforming the energy stored in the flywheel back into electricity. Vehicle braking was electric, and some of the energy was recycled back into the flywheel, thereby extending its range.

Source: Wikipedia: Gyrobus

Thanks for your response. Much appreciated. Do I understand it correctly that I’ll be able to add more drives later in JBOD mode, but I’ll simply have to power it off before adding or swapping drives?

I’m in the same situation as you, more or less… I have three new 22TB drives that need an enclosure, preferably for JBOD (no hardware RAID needed) but I can’t figure out which ones are actually good products… I don’t mind using a random-brand product if it’s actually solid.

I find it very difficult to figure out which ones will support my 22TB drives. And for some of them, it seems, it’s impossible to add new drives to empty slots later (because of hardware RAID, I guess?), which has made me hesitant in buying one with more slots than I have drives, in case they can’t be utilized later on anyway…

I was looking at the QNAP TR-004 which was mentioned by someone else somewhere on Lemmy some months ago, but IIRC it would be impossible to use the fourth slot later if the drive isn’t included in the hardware RAID configuration…

EDIT: I have also been looking into so-called “backplanes” as an alternative, since they seem to do the job and are cheaper, but I’m unsure if I’ll need a PC chassis/case/tower for that to actually work?

If you find something good (products or relevant info), feel free to share it with me.