3 ms·
A much better and denser option for storing energy mechanically is flywheels. I haven't researched what happened to this option since but when I was looking int
by swombat 10y ago
A much better and denser option for storing energy mechanically is flywheels. I haven't researched what happened to this option since but when I was looking into it 15 years ago it seemed like a good option that needed more R&D into frictionless axles and vacuum chambers.
- dredmorbius 10y agoExcellent rapid response, second only to capacitors. But pretty poor densities, and hugely significant engineering challenges. Flywheels that don't become fly-apart wheels is one problem. Containment of fly-apart wheels another. Buried concrete pipes are usually what you're looking at. You need mass to contain these things. The per-kg energy densities just aren't all that high. If you want reactive load to soak up very short-term demand / supply fluctuations, you can get that. And you've got crazy charge-discharge cycles. Bearings are mostly solvable with magnets, as I understand. But you still lose a given percentage of storage over short time -- ~1% per hour or so, within a few powers of 2. Enough that long-term storage isn't viable. And the thing that really screws you over is that the Earth moves. Geometric precession of your flywheel is something you've got to deal with. There's a place, but I don't think it's large-scale, long-term grid storage.
- pjc50 10y agoThe Formula 1 "KERS" system is based around high-speed flywheels and seems to work quite well.