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1. Nitrogen-14 has 0.99998807418 of the mass of carbon-14. 2. After 1 year, 0.99987945993 of the original carbon-14 will remain. 3. 1 carat of pure carbon-
by saalweachter 7y ago
1. Nitrogen-14 has 0.99998807418 of the mass of carbon-14.
2. After 1 year, 0.99987945993 of the original carbon-14 will remain.
3. 1 carat of pure carbon-14 diamond will therefore lose 287.5 picograms of mass in 1 year.
4. 287.5 picograms of mass equates to 25,839.2 joules of energy.
This amounts to 0.818 milliwatts / carat for the first year (and a very slow decline after that). Note that this is the maximum possible output for a pure carbon-14 diamond. Usable energy will be less, and I'm assuming that the diamonds would not start out as pure carbon-14. Practical outputs are probably in the small-number-of-microwatts / carat range.
- zaroth 7y agoSo 1 gram of perfectly pure carbon-14 would produce theoretically 4mW essentially continuously, or 35Wh per year. I think that’s pretty neat. There are bursty low energy communication devices which could perhaps work with that power budget? The problem is, nothing in the world actually needs to stay on for 5,000 years. So the alternative of using a 100x cheaper battery that just lasts 6 months or something is going to be hard to beat.
- saalweachter 7y agoFor more human-scale applications, you're probably looking for something that has a half-life of ~650 years -- that gives you > 90% original power for 100 years.