Wayback Machine: Solar Power From Contracting Wires, 1932
by Lloyd Alter, Toronto 
on 09.18.07
We have seen some wierd and wonderful ideas from the past through Modern Mechanix, but this one has us scratching our head. A parabolic reflector focuses heat on tungsten wires stretched the length of the drum, lengthening under the heat. As the drum turns, the wire hits cold water and contracts. "As the drum rotates the wires pass out of the focal range of the sun’s rays and are doused in a trough of water at the bottom. Sudden cooling of the wires causes them to contract rapidly, pulling on a bell crank at the end of the drum. This action in turn causes the dogs to engage notches in the fixed ratchet and drive the drum around. Rotation of the drum causes the shaft to which it is fixed to revolve and operate the pulley on the same shaft" Of course, General Electric bought the patent so nobody else could have this and put them out of business.::Modern Mechanix
Follow @TreeHugger on Twitter & get our headlines with @TH_rss!
Thirsty for more? Check out these related articles:
- How to Use a Solar Oven: Beans and Rice Recipe
- How to Use a Solar Cooker: What Works and What Doesn't
- Find Your Dinner at the Farmers' Market: Peas and Prosciutto
- 7 Great Weekend Solar Power Projects
- 5 Reuses for CDs: Turn Old CDs into New Geek Gear
- 5 Reuses for Altoid Tins
How do you keep the water from heating up?
I remember seeing a rubber band heat engine that spins when the "spokes " are immersed in water. Here is a video of a bicycle wheel with the spokes replaced by rubber bands. When you shine a heat lamp on one side, it spins.
http://www.arborsci.com/CoolStuff/RubberBandEngine.mpg
I agree with nick how do you keep the water from heating up?
Sounds like a recpie for stress fractures in the wire if you ask me.
And a small wire in a big drum of water won't transmit that much heat. If it were kept in a metal tank, I'm sure it would be able to dissipate enough heat.
I think it raises the question of patenting technology for anti-competative purposes. I wonder whether that is illegal. If it isn't, perhaps it should be.
Aluminium fins?
You would need a source of fresh water - spring, lake, stream. That standing water would get hot very quickly even with fins.