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ORNL Restores US Capability To Produce Plutonium-238 (ornl.gov)
hypnosec writes: Oak Ridge National Laboratory has successfully produced 50 grams of plutonium-238, an isotope that produces heat without a lot of other, problematic radiation. This makes it suitable for use in radioisotope thermoelectric generators, which can power space probes. The new sample effectively revives the U.S.'s end-to-end plutonium-238 production capabilities, which have been dormant for around 30 years since work was stopped at the Savannah River Plant in South Carolina. The ORNL is optimistic this important milestone will pave the way for regular production of the material, ensuring constant supply for NASA's future missions.
Yes, it is radioactive, and yes, it is a very nasty heavy metal... but there are still pacemakers ticking away with this stuff as the "battery" 25+ years later.
I wonder if Pu-238 might have some use in areas where batteries are needed and extremely hard to replace other than space projects. Definitely not for a battery for a smartphone, because we don't want Youtubers like TechRax to get radiation poisoning, but airline flight data recorders come to mind.
All plutonium isotopes are not made equal.
Pu-238 = great source of heat, not a great source of boom.
Pu-239 = great source of boom, not a great source of heat.
Pu-240, Pu-241 = not a great source of boom or heat.
Pu-238 is not used in weapons specifically because it fissions too fast spontaneously. That's why it makes so much heat. And, because of this, your weapon would have a significant portion of it reduced to not-plutonum and neutron poisons by the time you want to use it.
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Pu-238 cannot be made into a bomb. It is not fissile. You may be thinking of another isotope.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
It looks like about 4 kg of plutonium-238 is required for a Mars Rover type mission. (Inferred from wikipedia article)
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The process described starts with a solid Neptunium-237 oxide, mixes it with Aluminum, presses it into pellets, irradiates it, chemically separates the Plutonium-238, and then processes it back into a solid oxide. They don't say where the Neptunium itself comes from, other than mentioning an existing inventory. It can be recovered from spent fuel, using another convoluted process starting with solid oxides.
Creating 237Np would be a far more direct process with a LFTR, where the 2% of the fuel which does not fission mostly finds its way to be this very isotope. (The remainder become short-lived fission products.) Naturally, processing a liquid is easier than going through multiple solid oxide steps, and lends itself to a continuous process capable of producing 238Pu in volume. It would be far more interesting if ORNL were developing the processes for this instead.
According to Wikipedia, one gram of plutonium-238 generates approximately 0.5 watts of thermal power. Thus, 2420 tonnes of Pu-238 will generate 1.21 GW for decades.
An alkaline AA battery weighs 23 g and can put out just over 1 watt of electrical power without overheating. You would need 27830 tonnes of them to output 1.21 GW for about 2 hours.
A golden hamster weighs 125 grams and apparently generates a maximum of 0.4 watts (according to google). This means you need about 378125 tonnes of hamster to generate 1.21 GW for a few hours.
Thus, PU-238 is clearly the most practical solution of those mentioned.
When Argumentum ad Hominem falls short, try Argumentum ad Matrem
Interesting facts.
PU-238 is hard to make.
AA batteries are easy to make.
Hamsters make themselves.
PU-238 is clearly the least practical solution of those mentioned. :)