Gerrit Bruhaug
@gbruhaug.bsky.social
Finally a real scientist with a real job. All bad opinions are my own, all good ones are my friends.
I picked up some light reading for the weekend. I'm excited to learn just how nuts those 50's/60's weapons scientists were!
September 21, 2025 at 6:46 PM
I picked up some light reading for the weekend. I'm excited to learn just how nuts those 50's/60's weapons scientists were!
I’m reminded of this great line.
September 19, 2025 at 7:04 PM
I’m reminded of this great line.
I was lucky enough to be able to see the SLAC facility (LCLS-II and I) yesterday. These are honest to god x-ray lasers! I would argue that this is probably the most useful scientific facility this country has made yet.
August 16, 2025 at 4:19 PM
I was lucky enough to be able to see the SLAC facility (LCLS-II and I) yesterday. These are honest to god x-ray lasers! I would argue that this is probably the most useful scientific facility this country has made yet.
I even got to see the treatment line and was gifted a collimator! This piece of brass was machined in the shape of someone’s tumor so as to make sure the proton beam only hits cancerous tissue.
August 13, 2025 at 10:10 PM
I even got to see the treatment line and was gifted a collimator! This piece of brass was machined in the shape of someone’s tumor so as to make sure the proton beam only hits cancerous tissue.
It’s always fun to get to see accelerators, especially such historic machines! This is using the steel from one of Lawerence’s original cyclotrons to make the Crocker cyclotron at Davis. It’s used for space radiation, isotope production, and eye cancer treatment.
August 13, 2025 at 10:10 PM
It’s always fun to get to see accelerators, especially such historic machines! This is using the steel from one of Lawerence’s original cyclotrons to make the Crocker cyclotron at Davis. It’s used for space radiation, isotope production, and eye cancer treatment.
So I see you are in Australia and honestly have no dog in that fight. Historically though, nuclear build outs still are in the top end for rate of displacing fossil fuels and shutting plants down is EXTRA bad. I see no reason to fight any clean energy personally.
July 21, 2025 at 1:25 AM
So I see you are in Australia and honestly have no dog in that fight. Historically though, nuclear build outs still are in the top end for rate of displacing fossil fuels and shutting plants down is EXTRA bad. I see no reason to fight any clean energy personally.
80 years on from Trinity, the true start of the Atomic Age. Here’s hoping none of us ever get to see the terrifying beauty of one of these monsters in the open. Credit @wellerstein.bsky.social awesome article for the quote!
July 16, 2025 at 2:43 PM
80 years on from Trinity, the true start of the Atomic Age. Here’s hoping none of us ever get to see the terrifying beauty of one of these monsters in the open. Credit @wellerstein.bsky.social awesome article for the quote!
With an EROI of ~466, that 10X reduction takes the CANDU down to ~46 using seawater uranium. Not great, but also not really worse than things we already use (like fossil fuels). And unlike the breed/burn scenarios, this is a mature technology! 4/6
May 17, 2025 at 4:29 PM
With an EROI of ~466, that 10X reduction takes the CANDU down to ~46 using seawater uranium. Not great, but also not really worse than things we already use (like fossil fuels). And unlike the breed/burn scenarios, this is a mature technology! 4/6
It's interesting to consider how other fuel cycles handle this though. We can see that different reactor technologies and even going for limited recycling, like France does, doesn't really help! The only two options seem to be the full breed/burn or... the humble CANDU! 3/6
May 17, 2025 at 4:29 PM
It's interesting to consider how other fuel cycles handle this though. We can see that different reactor technologies and even going for limited recycling, like France does, doesn't really help! The only two options seem to be the full breed/burn or... the humble CANDU! 3/6
There are a wide variety of claims, but this DOE report seems like the best researched and most balanced. It's a bit behind on the tech, but still the numbers are painful. We lose ~10X for LWRs! 2/6 www-pub.iaea.org/iaeameetings...
May 17, 2025 at 4:29 PM
There are a wide variety of claims, but this DOE report seems like the best researched and most balanced. It's a bit behind on the tech, but still the numbers are painful. We lose ~10X for LWRs! 2/6 www-pub.iaea.org/iaeameetings...
So in when talking about nuclear power in the long term, seawater extraction often comes up. A slightly less often discussed aspect is the Energy Return On Energy Invested (EROI) of this process. This tell us if the whole thing is even worth thinking about. 1/6
May 17, 2025 at 4:29 PM
So in when talking about nuclear power in the long term, seawater extraction often comes up. A slightly less often discussed aspect is the Energy Return On Energy Invested (EROI) of this process. This tell us if the whole thing is even worth thinking about. 1/6
I always wondered what that thing was made for and was just told "SDIO". Apparently there were other plans in the 90s! We are now nearly 30 years on and I think this sentence may be true... Although the safety aspects for other troops are a big question! 4/4
April 26, 2025 at 5:58 PM
I always wondered what that thing was made for and was just told "SDIO". Apparently there were other plans in the 90s! We are now nearly 30 years on and I think this sentence may be true... Although the safety aspects for other troops are a big question! 4/4
The thing that really stood out to me though was the accelerator technology. It relied on a sort of induction linac/synchrotron hybrid, and one I am VERY familiar with. We had a SLIA (maybe the only one?) at the IAC in Idaho! It is now back-up parts for DARHT. 3/4
April 26, 2025 at 5:58 PM
The thing that really stood out to me though was the accelerator technology. It relied on a sort of induction linac/synchrotron hybrid, and one I am VERY familiar with. We had a SLIA (maybe the only one?) at the IAC in Idaho! It is now back-up parts for DARHT. 3/4
What's extra wild is that they tested this with actual beams and HE! This work also built upon years of work figuring out how to propagate beams in atmosphere in "pinched" conditions. 2/4
April 26, 2025 at 5:58 PM
What's extra wild is that they tested this with actual beams and HE! This work also built upon years of work figuring out how to propagate beams in atmosphere in "pinched" conditions. 2/4
Wild paper I was recently pointed to. "Energetic Charged Particle Beams for Disablement of Mines". The idea is to shoot a high energy (~250 MeV) electron beam into the soil and detonate a mine from afar! You could also use the beam to help detect mines. 1/4 www.osti.gov/servlets/pur...
April 26, 2025 at 5:58 PM
Wild paper I was recently pointed to. "Energetic Charged Particle Beams for Disablement of Mines". The idea is to shoot a high energy (~250 MeV) electron beam into the soil and detonate a mine from afar! You could also use the beam to help detect mines. 1/4 www.osti.gov/servlets/pur...
Now the paper has conclusions based on naval reactor costs and comparing to the cost of fuel getting to an aircraft carrier. We can see that the fuel is more expensive, around $11/gal for the full reactor case, but for the USN that may be fine. They already pay >$5/gal for delivered fuel! 4/8
April 9, 2025 at 4:51 PM
Now the paper has conclusions based on naval reactor costs and comparing to the cost of fuel getting to an aircraft carrier. We can see that the fuel is more expensive, around $11/gal for the full reactor case, but for the USN that may be fine. They already pay >$5/gal for delivered fuel! 4/8
All options need electricity and heat, so it's a good match for nuclear power! We can see that the best case options need 49 MWt and 152 MWe for 1.7 tons/hr of JP-5. That is about 550 gal/hr of fuel. 3/8
April 9, 2025 at 4:51 PM
All options need electricity and heat, so it's a good match for nuclear power! We can see that the best case options need 49 MWt and 152 MWe for 1.7 tons/hr of JP-5. That is about 550 gal/hr of fuel. 3/8
So this paper looks at multiple options for synthetic fuel production via CO2 trapped in water and then doing direct electrolysis. This is MUCH better than DAC, so this is already best case scenario. 2/8
April 9, 2025 at 4:51 PM
So this paper looks at multiple options for synthetic fuel production via CO2 trapped in water and then doing direct electrolysis. This is MUCH better than DAC, so this is already best case scenario. 2/8
Since a certain nuclear start-up is talking a lot about synthetic fuels from nuclear, I wanted to take another look at the economics of the whole idea and what it would take to make it make sense. I am basing this all off this wonderful paper looking into this idea for aircraft carriers. 1/8
April 9, 2025 at 4:51 PM
Since a certain nuclear start-up is talking a lot about synthetic fuels from nuclear, I wanted to take another look at the economics of the whole idea and what it would take to make it make sense. I am basing this all off this wonderful paper looking into this idea for aircraft carriers. 1/8
Nothing makes you feel out of shape like a beautiful day skiing in fresh snow. I need to jog or something more…
March 9, 2025 at 9:00 PM
Nothing makes you feel out of shape like a beautiful day skiing in fresh snow. I need to jog or something more…
In case anyone who follows me on here lives in New Mexico, my wonderful wife has organized this event for international women’s day this Saturday in Santa Fe. We would love to see anyone and everyone who is interested!
March 6, 2025 at 6:50 PM
In case anyone who follows me on here lives in New Mexico, my wonderful wife has organized this event for international women’s day this Saturday in Santa Fe. We would love to see anyone and everyone who is interested!
It's also interesting to look at the costs. For case (A) we can almost get competitive with delivered JP-5 price and if it was on price alone the capability would be worth it. For (B), the reactor cost seems to be the real killer. Gotta get cheaper reactors for this to work!
February 4, 2025 at 8:54 PM
It's also interesting to look at the costs. For case (A) we can almost get competitive with delivered JP-5 price and if it was on price alone the capability would be worth it. For (B), the reactor cost seems to be the real killer. Gotta get cheaper reactors for this to work!
The big issue is the system volume and mass... The absolute smallest option requires 2.53E4 m^3 and 4.07E4 tons of mass! It would eat over 1/3 of the displacement mass of a Ford carrier with synthetic fuel equipment alone!
February 4, 2025 at 8:54 PM
The big issue is the system volume and mass... The absolute smallest option requires 2.53E4 m^3 and 4.07E4 tons of mass! It would eat over 1/3 of the displacement mass of a Ford carrier with synthetic fuel equipment alone!
Now on the energy balance side, the requirements are high but not too nuts considering the inefficient path taken. The Ford class carriers have two reactors estimated to be ~700 MWt and 125+ MWe, so adding enough nuclear power is definitely doable. Using reactor heat would help as well.
February 4, 2025 at 8:54 PM
Now on the energy balance side, the requirements are high but not too nuts considering the inefficient path taken. The Ford class carriers have two reactors estimated to be ~700 MWt and 125+ MWe, so adding enough nuclear power is definitely doable. Using reactor heat would help as well.