Interesting..metal used to heat and cool

HydroNiCK

https://newatlas.com/shape-memory-alloy-nitinol-heating-cooling/58837/

mikeg2015

I wonder what efficiency impact an increase in temperature has? If i bend it at 100F outdoors and uncoil it at 75F, does if operate with the same efficiency?

How large of a spool do you need per ton of cooling?

Can I connect it to a bicycle if the power goes out? Actually I see a great application from wind power and micro hydro where you can use old school motive power from either in developing countries.

In theory, heat transfer is decoupled from temperature, so you can change latent/sensible ratio and total capacity simply by carrying rotational speed.

The challenge is that in retrofits you will still need a water cooled system to pump heat a longer distance.

nibs

What a fantastic site, learned about the molecules that store heat from sunlight, now this, heat/cold from bending metal.
Thank you, many of us come here to learn, and it works.

ddunn

Interesting. But 36F isn't a very large delta between the hot side and the cold side.

nibs

Stack two units for a 72F delta?

Fred

Great concept. Metal fatigue likely to be one of the major hurdles to overcome. I'm also wondering what size the bundle will need to be to be effective for heating/cooling (obviously driven by conditioned area to be heated/cooled) and at what speed the winding/unwinding must occur?