71–80 of 135 posts
I actually like the recirculation simulation. Although all kinds of cyclical engines have recirculation of power as part of their function, in fusion there is an important difference from what people are used to. In an internal combustion engine, the crankshaft and flywheel in a car recirculate power from the power stroke to the compression stroke, doing the same thing as the recirculated energy does in this simulati…
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It already exists in many countries. They transport it through pipelines . E.g. Temelín Nuclear Power Plant, Paks Nuclear Power Plant And many more
My question is more about the safety of locating one smack in the middle of a city. There is radiation to shield but no radioactive fuel waste. HOWEVER, worn reactor parts that need to be replaced will be piping hot when measured with a Geiger counter. So is it safe to build and operate in the middle of e.g. NYC? And further, if they are safe, what is the public's perception of fusion? Do people hear "nuclear fusion"…
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There's only a few grams of hydrogen in the reactor's plasma, it's reaction with oxygen wouldn't be much more exciting than just losing containment. There are engineering challenges that have to be addressed but no worse than the 6 MW research reactor I used to walk by every day to my college classes in the middle of a dense city. The proliferation risk of someone using the neutron flux to produce an atomic or dirty…
I think the proliferation risks will be in future the reason, independent of technological obstacles or costs, why US will not allow to build fusion power plants in all countries around the world. Hybrid nuclear fusion–fission power plants have been already proposed and studied in theory. "In general terms, the hybrid is very similar in concept to the fast breeder reactor, which uses a compact high-energy fission cor…
Apologies if I've missed something, but isn't this all just a fantasy? None of the current methods for getting fusion power are even close to being practical -- even the theoretical net output experiments require extensive and sensitive measurement setups just to establish whether or not they are positive energy. We are not in a place where we expect fusion power to be incrementally achieved by the current systems. W…
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There's only a few grams of hydrogen in the reactor's plasma, it's reaction with oxygen wouldn't be much more exciting than just losing containment. There are engineering challenges that have to be addressed but no worse than the 6 MW research reactor I used to walk by every day to my college classes in the middle of a dense city. The proliferation risk of someone using the neutron flux to produce an atomic or dirty…
I think the proliferation risks will be in future the reason, independent of technological obstacles or costs, why US will not allow to build fusion power plants in all countries around the world. Hybrid nuclear fusion–fission power plants have been already proposed and studied in theory. "In general terms, the hybrid is very similar in concept to the fast breeder reactor, which uses a compact high-energy fission cor…
Modern fission power plants are designed with a reactor vessel to last a century and to withstand high pressures and temperatures. It's built and emplaced permanently in a large concrete shielding structure.
In a hybrid design this just won't work. Fuel will need to be right next to a high-vacuum chamber that will need periodic maintenance.
A good addition would be the sales price per MWh, price for the power plant, and the loan interest rate. Because IMO all that is extremely critical. I fully support the pursuit of fusion as a scientific endeavor, but given that we're probably at least 30 years away from having anything approaching commercial deployment (assuming ITER is built, works, is followed promptly by DEMO, it works, and is followed promptly by…
That's not really how it works. ITER has a budget measured in billions over multiple years, the global energy industry is trillions every year. The amount needed to do the research is such a small proportion that if there is even a tiny possibility that it could long-term provide a significant proportion of world energy, it's well worth doing the research. The scientific knowledge gain is just icing on the cake.
> That's a lot of time for the world to get worse while waiting for fusion to happen, and we might as well just throw renewables at the problem now instead of waiting.
We can do two things at once.
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True, but we've built tokamaks and we're building ITER, which so far has an estimated price of between $45 billion and $65 billion. Now of course that's a research reactor full of experiments and instrumentation that wouldn't be part of a normal power plant, but given current experience that I think we can expect we won't suddenly knock down the cost to $100M. It's going to be somewhere in the billions. And we have e…
I think a lot of the cost is custom parts. Standardization and economy of scale would bring the price down quite a bit.
fantastic PBS Space Time on what the last steps are going to be to finally make fusion possible https://www.youtube.com/watch?v=nAJN1CrJsVE (fusion is -always- just a decade away, perpetually, lol)
It's a nice video, but a striking thing about it is that it ends with "I just want my infinite free energy". Where on earth is that supposed to come from? Fusion is ultimately a fancy way to boil water. The tokamak (or stellarator) heats a given amount of water per second, which after losses to power the plant itself and the losses in the steam turbine, makes some finite amount of MWh to output to the grid. This cont…
Since you'd still end up having to build a gigantic heat exchange setup with steam turbines, pipes/ducts/pumps, generators, valves, gauges, vents, maybe even a cooling tower, etc. Plus a labyrinth of catwalks, ladders, access tunnels for workers in hard hats servicing/inspecting/replacing stuff who are on-site 24/7 and exposed to non-trivial occupational hazards dealing with superheated liquids at high pressure every day.
The entire concept of a steam turbine is just fundamentally a big hassle compared to an inexpensive solid state slab + batteries that are modular and basically plug-and-play by comparison.
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Storing renewables for a whole season is an unsolved problem at the moment. Countries at higher latitudes might want fusion for baseload generation during winter. And later it'll help with climbing the Kardashev scale.
But there's far easier solutions to that than fusion. For example, HVDC. Interconnect and buy power from somebody with more sun. Or just overbuild solar by a lot. It's cheap, so chances are having too much of it still works out economically.
Who is Japan interconnecting with, or any other country that doesn't trust its neighbors? What is Canada supposed to do when it's ~6000 km from the equator and might not want to rely on the US for electricity regardless?
> Or just overbuild solar by a lot. It's cheap, so chances are having too much of it still works out economically.
Solar is cheap per kWh but those kWh come disproportionately in the sunnier months of the year at any non-equatorial latitude. To build enough for January you'd then have oversupply and a price of zero for the nine months out of the year when you have the most output, requiring you to make back the entire cost in the three months when solar output is lowest. Then you're only getting paid anything for e.g. 12.5% of the kWh you generate (the 25% of the months that have 50% of the average output) which means you need the price during those months to be 8x the average price you need to break even, but then you're not cheaper than existing alternatives. And that's before you even deal with nights or cloudy winter days.
It obviously makes sense to use solar to reduce the need for natural gas plants during hot summer days with a lot of air conditioning demand, or for charging electric cars that can hold off a couple days if it's cloudy. It equally obviously doesn't make sense to try to generate 100% of electricity from the same intermittent source whose output is regionally correlated by season and weather systems.
A good addition would be the sales price per MWh, price for the power plant, and the loan interest rate. Because IMO all that is extremely critical. I fully support the pursuit of fusion as a scientific endeavor, but given that we're probably at least 30 years away from having anything approaching commercial deployment (assuming ITER is built, works, is followed promptly by DEMO, it works, and is followed promptly by…
We have spent about $10T on renewables over the last 20 years. We use more FF today than 20 years ago because renewables don't provide enough power to compensate for the normal yearly increase in energy demand (which is pathetic). The solution is nuclear (fission). It was the solution before we were born. It will be the solution after we die. No amount of politics and propaganda will ever change that. The laws of physics care nothing about what you think.