More Nuclear Batteries

[Todg]

Aside from the betavotaics mentioned in anothetr thread, I found another novel power source that uses a beta source to generate electricity.

Here's the essential description:

"...ingenious nuclear micro-generator that uses a beta-emitter to charge a MEMS cantilever connected to a piezoelectric crystal. Alternately charging and discharging the cantilever beam performs work on the piezoelectric crystal and generates power. A few microcuries of tritium provides an energy equivalent of 2400 Li-ion batteries of the same weight. Of course, energy density is just part of the picture. How much tritium would be required to provide the continuous power for my laptop (that has a 50 Watt-hour Li-ion battery that runs for 4 hours in normal use)? The answer [from the article is:] the needed 150 grams of chemical energy storage for the Li-ion battery can be replaced by 0.06 grams of tritium plus the mass of the MEMS devices needed for energy conversion

 

[Todg]

The fgull text of the article can be found here:

http://homepages.cae.wisc.edu/~blanchar/res/Spectrum01330808.pdf

 

[Todg]

Also, we have the trusty old RTG (Radioisotope Thermoelectric Generator). These have a proven record in spacecraft, but probably offer significant risk, although I see the Soviet/Russian goverment uses Sr-90 RTGs to power lighthouses.

Pu-238 based RTG can generate about 0.5 KW per kilo. Sr-90 RTGs aren't as efficient.

 

[Anthony]

I don't find that quote anywhere in the article, which is not surprising, as with the 8% efficiency they give, 12.5W would require somewhere over 600g of tritium (at which point you can power the laptop for 5 years, but...)

 

[Todg]

I should learn not to post late at night.

The quote came from a reviewer:

http://homepage.mac.com/mauel/blogwavestudio/LH20040901155655/LHA20040902145520/

in reference to this article.

http://www.spectrum.ieee.org/oct05/1542

Sorry for the confusion. Listen to Anthony. He knows what he's talking about.

 

[Uncle Bob]

600 g of tritium in my laptop. In my lap ...

<Humm, Humm ... chestnuts roasting by an open fire ...>

It was a grand idea while it lasted

 

[Andrew Boulton]

You don't need tritium for that...

http://www.warphead.com/modules/news/article.php?storyid=8

 

[Todg]

You'd think he would have noticed the heat?

 

[Fritz_Brown]

Corejob, I'm surprised the Soviets didn't power laptops with those things, given some of the, um, less than ideal choices they made at times.

Dear Lord, can you imagine Windows power management with a small nuclear device in the same laptop? Worse yet, a virus/trojan that causes some kind of runaway in the power?

 

[Anthony]

Speaking of the soviets and RTGs: http://www.bellona.no/en/international/russia/navy/northern_fleet/incidents/31772.html
http://nuclearno.com/textml.asp?7198

A particularly interesting one from the second (probably the same as the Lia incident from the first):

in 2002, three hunters in the former Soviet republic of Georgia were severely irradiated after stumbling across an RTG that had been in the wood for years. Huddling around the strontium battery as a heat source, all three spent months in the hospital battling radiation sickness.

 

[Fritz_Brown]

Ouch!