2y ago

Powering a Car with Liquid Air - Peter Dearman

Powering a Car with Liquid Air | Trailblazers | BBC Earth Lab

13 comments

That concept is decades old and has been used for small trains in closed areas. There's a decommissioned locomotive on display in Hamburg that was powered by compressed air.
Or use a Perendev magnet motor... should be more efficient anyway.
- Liquid air motors don't violate the laws of thermodynamics. It runs on energy stored as cooled air, similar to a compressed air cartridge.
  If the motor design doesn't account for entropy, it won't work. Perendev magnet motors, like all permanent magnet perpetual motion machines, don't work.
  
  I've seen tons of other videos that disprove this one... which one is right? IDK, I guess I'll have to build one and see.
  And it's not free energy, the magnets become demagnetized with time, which is logical, they push or pull on one another. On a long enough time scale, yes, they do become less magnetized.
The issue is always energy density and round-trip efficiency, and I don't see numbers for either of these. Remember that you do have to actually liquify the air first, and that takes power.
- Yes, no-one is claiming this car runs on free energy. The advantages are a light-weight mobile energy source and zero-emissions. The expansion ratio IIFC is like 80% that of gasoline, which isn't terrible. Condensing air is a process that is energy intensive, but does not require non-renewable energy to perform.

13 comments