Nitinol heat motor for sale

http://www.grand-illusions.com/acatalog/Heatmobile.html

That one is for sale.

http://m.youtube.com/watch?v=AVCX5BfPn6A

That is a video demonstrating it in action.

No, it's not a powerful enough motor to do much work, but what if it was upscaled and set up to run on solar heated water or oil? Or, what if a better configuration were found?

This is just a technology that might be worth keeping an eye on. Already, this memory metal is being used as a passive, automatic solar tracker that requires no external power, aside from sunlight, to turn/track solar panels and concentrators with the sun. Perhaps more uses will be identified and acted upon in the future.

I assume (I know, there is the ASSume word) that a second motor (another 2 pulley/nitinol loop) will double the HP. Or, would a thicker looped band provide usable HP? Seems like the water temp should be only slightly above the activation temp so it can cool and soften before it reaches the top pulley. How about a nitinol spring that could wound tight with little effort/expended energy when cool, then heated via an environmentally friendly heat source and released to unwind and do work?

I don't know what the future holds for this freaky metal. Maybe it will always be too expensive for practical energy applications, or maybe the cost will come down if people create a demand for it. Guess the first step is people becoming more aware of nitinol's potential to the point where this becomes common knowledge. If enough people know about it, perhaps more experiments will be done to explore the possibilities of using it for energy, and those experiments would be openly shared, leading to an eventual demand from consumers and a price drop.

Different grades activate at different temperatures, so that seems to open nitinol to many different possible applications in different environments. Perhaps a nitinol motor could use waste heat in a hybrid vehicle's engine to charge the battery for higher efficiency, or replace the alternator on regular vehicles.

The first nitinol motor was built and studied in the 1970's, nearly 40 years ago. It appeared to be more powerful than the toy I linked to above, judging from the old footage. Funding for the program stopped shortly after that motor was demonstrated. Seems past time to find out if it can contribute to producing clean energy.

Unfortunately the nitinol motors lacked durability and would fail in far too short a time to make them viable.

Max, I wondered about the functional life of this material. Do you have a link to information about the working lifespan of nitinol? Barring that, where did you get this information and what was the duration of the working lifespan, if you can remember.

I have heard that stressing this metal by loading it beyond it's recommended capacity will shorten the working life.

I'll go back and reread data from that first nitinol heat motor. I don't remember how many cycles it ran before the project shut down or if it was ever put under a load.

Looking at that toy, it seemed like a more efficient way to run it might be to set a sponge touching the wire at the hot point, then drip hot water onto the sponge from a thermos. Might run longer that way for a given batch, the premise being that the batch of water in the thermos wouldn't cool as fast as the water in an open bath and only the necessary amount (less) would be used only at the working point. Less heat loss of the batch to the environment per minute.

Not sure of the fatigue referenc but it was also given up due to low conversion efficiency as found on pg 138 of this reference. http://www.researchgate.net/publication/222067522_Non-medical_applications_of_shape_memory_alloys

http://ufos.homestead.com/nitinol-evolution.pdf

This is a bit more about Nitinol's uses and limitations. It has quite a few applications outside energy production. It seems that the longevity was improved by refining the manufacturing technique, but that doesn't mean it has yet become practical for power generation, or ever will.

It's an interesting and useful metal, at the least.