Total Non-NASA Missions: 8 (APL 9)Number of Non-NASA RTGs: 10 (APL 11)
During the decadal survey we commissioned a study on small fission power reactors. I'm attaching it here.In all honesty, we did this because John Casani requested it and Casani is a legend (and nice guy). But I think there was little support for it among the planetary science community. At the very least they wanted the Pu-238 production line restarted so that they could consider missions that had been proposed in the recent past. Small fission reactors would be nice to have for more ambitious planetary missions, but there are no realistic missions that could use them that anybody could foresee in the next several decades.
Thanks cartman, but SNAP-10A is a nuclear reactor, not a radioisotope thermolelectric generator (RTG).
It's a pity we don't use the Thorium fuel cycle in our commercial reactors. One of the waste byproducts of the reactor is non-weapons grade plutonium that can be used in Pu-238 applications. We'd never run out. Some redesign of the RTG's would be needed of course, but there would never be another problem with the fuel supply.
Questions.1) The 2020 startup of fresh Pu-238 will produce approx 1kg./year. Is the entire new Pu-238 production available to NASA, or is DOE actually producing fresh Pu-238 per year at a higher rate for "other" non-NASA uses?2) Does this future fresh approx. 1kg/year for NASA production limit any possible human/SLS mission to Mars? A more basic wording, will a human/SLS mission to Mars require any sort of Plutonium power sources?
Quote from: Hog on 03/30/2014 04:23 amQuestions.1) The 2020 startup of fresh Pu-238 will produce approx 1kg./year. Is the entire new Pu-238 production available to NASA, or is DOE actually producing fresh Pu-238 per year at a higher rate for "other" non-NASA uses?2) Does this future fresh approx. 1kg/year for NASA production limit any possible human/SLS mission to Mars? A more basic wording, will a human/SLS mission to Mars require any sort of Plutonium power sources?1-I thought it was more like 1.5 kg. The material is for NASA use. NASA is paying for it after all. DoE is not producing any other material. In fact, the infrastructure is really crumbling and they need to rebuild it. However, I suspect that NASA's memorandum of understanding with DoE allows DoE to claim that material for other use if necessary (for national security purposes).2-Human missions to the Moon and Mars will probably require RTGs as backup power supplies. That would increase the need for more material and NASA will have to pay for it. Restarting production of any material at all is an important first step. But it is my understanding that increasing production from the rate that they have decided on will be a significant expense. That will require more material.
In 2012, after a few false starts, the Obama administration got Congress to go along with a plutonium-238 restart, under the condition that NASA pay to repair aging DOE infrastructure at the Los Alamos National Laboratory in Los Alamos, New Mexico. When the repairs are complete, the Energy Department will start producing 1.5 kilograms of plutonium-238 a year.“The question is when that starts,” Caponiti told outer-planets scientists. She said that even if production does not immediately ramp up to 1.5 kilograms a year when the new equipment comes online, “something less than the full production rate” could still support NASA’s needs.This is because plutonium-238 decays over time (its half-life is just under 90 years), meaning the longer the fuel is stored, the more energy it loses. Of the 35 kilograms reserved in the U.S. stockpile for civil space programs, 17 kilograms meet DOE’s minimum required energy levels. The other 18 kilograms do not, but could be refreshed by an infusion of newly refined plutonium-238.Even if production gets off to a slow start, any new plutonium-238 helps and “is going to have an immediate effect on missions,” for the better, Caponiti said.Also at the meeting, Ralph McNutt, a planetary scientist who led a NASA-chartered study of the agency’s future nuclear needs, briefed the group on the results.The Nuclear Power Assessment Study examined both robotic and crewed mission concepts planned by NASA and the broader space science community over the next 20 years and concluded “nuclear power systems are certainly going to be needed during that time period,” McNutt said.His presentation marked the first public summary of the study since its November completion. The 185-page report is the product of about six months of work and has not been released because of security concerns, McNutt said.
Under the Efficient Space Exploration Act, filed July 22 by U.S. Sens. Sherrod Brown (D-Ohio) and Robert Portman (R-Ohio), NASA and the White House Office of Science and Technology Policy would take the lead on a study to determine the space agency’s exact requirements for radioisotope power systems, the plutonium-238 that fuels them, and the risks to planned missions if those needs are not met.The bill — filed at a time when the U.S. plutonium-238 supply is dwindling and budget cuts forced NASA to cancel development of a more efficient nuclear battery under development at a NASA facility in Ohio — also directs the White House to ensure the Department of Energy, which is responsible for U.S. plutonium production, does not overcharge NASA for plutonium infrastructure upgrades at DOE’s Los Alamos National Laboratory in New Mexico.
[...] just put some money into it [...]
Read the article. It looks like some people in Ohio at the company and probably the NASA field center have been bending the ears of their senators and that's where this comes from. They're not interested in production, they're interested in restarting the ASRG program. I don't see that happening because it requires money that NASA doesn't have.Recently NASA has talked about restarting Pu-238 production by the end of this decade or even by 2020, which is really puzzling considering that it was originally supposed to start around 15-16. Either it's costing more money of NASA's budget is being short-changed (or both). I also wonder if taking the Europa mission out of the mix reduced the pressure to actually restart production--if true, that's typical, and it has been the problem all along: everybody is always looking for another excuse to kick the can down the road.I helped run the last big study on this issue and I'm not sure why another one is really needed. The solution is pretty straightforward, just put some money into it and get production restarted.
A further update.Ohio Senators Call for Plutonium Power Report with New Bill QuoteUnder the Efficient Space Exploration Act, filed July 22 by U.S. Sens. Sherrod Brown (D-Ohio) and Robert Portman (R-Ohio), NASA and the White House Office of Science and Technology Policy would take the lead on a study to determine the space agency’s exact requirements for radioisotope power systems, the plutonium-238 that fuels them, and the risks to planned missions if those needs are not met.The bill — filed at a time when the U.S. plutonium-238 supply is dwindling and budget cuts forced NASA to cancel development of a more efficient nuclear battery under development at a NASA facility in Ohio — also directs the White House to ensure the Department of Energy, which is responsible for U.S. plutonium production, does not overcharge NASA for plutonium infrastructure upgrades at DOE’s Los Alamos National Laboratory in New Mexico.- See more at: http://spacenews.com/ohio-senators-call-for-plutonium-power-report-with-new-bill/#sthash.k9YzmC3w.dpuf