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Meta-question about fusion energy -something I don't understand about the movement. I spent a few years as CTO of a company providing heat-to-electricity plants

• mchusma 5y ago
  Id answer this in 2 ways: First. Let's say we have a trillion people in space stations/multiple planets. Fusion is a energy source that can plausibly power them. Second. fission works close to other sources, but is so hampered by regulation that it hasn't gotten to be affordable. This may be fixed in the future. micro-reactors solve the biggest economy of scale issues and a renewed bipartisan interest in nuclear could help it be politically viable. If fission works in theory, fusion definitely works in theory (as the energy output is much higher).
• asdff 5y ago
  That just tells me that we haven't priced the externalities of carbon based energy appropriately, if the green solution is still more costly. Increase the carbon tax and things will pencil out fast.
• orangepurple 5y ago
  You can't put a price on energy independence in a free market economy. Energy independence is a military objective and a matter of national security. The costs are difficult to put in perspective.
  • BizarroLand 5y ago
    Oil companies are subsidized to the tune of Billions of dollars an hour. Subsidizing fusion energy would merely be redirecting that money to the greater payoff.
    • 420official 5y ago
      This is not true.. 1 billion an hour is 8.76 trillion a year yet you say "billions" an hour which would make it at least 17.52 trillion a year which is basically the entire GDP of the us. Certainly oil companies are subsidized but not "to the tune of" the entire US GDP.
    • pstrateman 5y ago
      The hyperbole isn't needed. Billions of dollars an hour is 17 Trillion dollars a year. They're not being subsidized by that much
      • akimball 5y ago
        Count the socialized cost of environmental remediation please. It will run into the quadrillion zone
        • orangepurple 5y ago
          The entire workforce of the United States will be deployed with a vegan toothbrush in hand to scrub the Earth of all the hydrocarbons
      • BizarroLand 5y ago
        I made a mistake, I should have said Millions of dollars an hour. Thanks for the correction
  • xondono 5y ago
    Of course you can. The price of energy independence is the lowest total cost that can keep up with energy demand. The question is if fusion is really the cheapest way to do it, say vs alternatives.
• 542458 5y ago
  I’ve wondered this as well. There is an argument that we’re dramatically underestimating the global warming impact of natural gas by underestimating/ignoring the impact of leakage.
• drumhead 5y ago
  High up front costs, for Nuclear fusion/fission, geothermal and solar but cheap fuel, you can run then all day long and sell the power you generate at any price to cover the fixed costs and pay off the capital costs and of course you're not generating carbon. With carbon burning generation, the cost of the fuel is volatile, sometimes its cheap sometimes it not, so you have to be clever in buying the fuel and not get stuck just buying spot and going bankrupt because its suddenly spiked in price.
• raywu 5y ago
  Your question is great and barring other incentives (comments in response to this), I’m also interested in how commercial viability impedes adoption. In your opinion, what could be done to make the energy generated by fusion competitive? Can we add storage to the mix and therefore compete on a longer time horizon? I know storage itself is expensive. Is it to say that fusion won’t get adoption from market forces alone, until the cost of construction lowers?
• red_trumpet 5y ago
  > even one where the onerous regulations go away and a market price on carbon is available What do you mean by a "market price of carbon"? From context I would guess that the "market price" would be higher than the current price, but the history has told us otherwise - that is why we have regulations on carbon emissions.
• pontifier 5y ago
  As someone trying to build a fusion reactor of my own design, I worry about this myself. I just have to believe that advancing the state of the art is a good thing, not a bad thing, and that my efforts will pay off.
• stkdump 5y ago
  You increase carbon taxes, outlaw fossil fuels and subsidize alternatives. This kind of innovation doesn't work without government intervention.
• mensetmanusman 5y ago
  Another way of asking this question is how long will the capital investment last? And what are the upkeep costs? Once we better understand this, governments would have the decision making expertise and an understanding of timescales involved to see if it is a worthwhile investment.
• vilhelm_s 5y ago
  Natural gas plants are cheap but they cause global warming, so soon we will not be able to use them. For example, the U.S. target is to have zero carbon emissions from electricity generation by 2035, and zero carbon emissions at all by 2050.
  • brightball 5y ago
    Their carbon emissions are still dramatically lower than those of coal and oil. There are bigger fish to fry than NG. NG is likely going to be a critical transitional fuel for the planet to depend on while we get to more abundant renewable options, grid batteries and nuclear/fusion/thorium.
    • adrianN 5y ago
      With NG you also have to take into account leakage from extraction and transport. Methane is a pretty strong GHG. I've heard that if you take that into account NG is not that much better than coal.
      • brightball 5y ago
        That makes sense but it seems like a problem that could be addressed if it was focused on.
        • blake1 5y ago
          Not really. The equipment to seal wells and pipelines against leaks would cost billions. We need more generation, but solar is already cheaper than new natural gas built on the leaky network. It makes more economic sense to just overbuild your solar at these prices. [1] $250mn for a single state: https://apnews.com/article/business-environment-and-nature-climate-change-7392636504b2763de07ff4b3fe78710e https://apnews.com/article/business-environment-and-nature-c...
    • beambot 5y ago
      What time horizon are NG plants capitalized over? Soon enough, that will be a significant factor in the economic equation...
• Mizza 5y ago
  It's political. Taxes on carbon pollution are inevitable, but for the time being there is still political blockage because of the power of the cartels.
  • Jeff_Brown 5y ago
    I wish it were just cartels that oppose a carbon price. The fact is it will make certain industries shrink, and almost no country in the world (certainly not the US) does much to take care of displaced workers, and the workers know it. Meanwhile the people who will have jobs in the new industries that spring up don't know it yet, so they don't fight for it.
  • Symmetry 5y ago
    Politically the problem is that voters want action on climate change but aren't willing to pay any visible cost associated with that action. If you put a tax on carbon that raises the price of something by $100 then that's a political no-go. But if you create a cap and trade system that raises the price by $150 that might be politically viable. Not ideal, but one has to compromise with political realities.
    • AnthonyMouse 5y ago
      The answer to this is for the tax to pay out to everyone as a dividend. Then voters would be in favor because some of the tax is paid by corporations but all of the money goes to individuals, so most people get back more than they pay. On top of that, the tax would (if enacted by most countries) crush demand for fossil fuels. So then fossil fuel prices go down by, for example, half the amount of the tax, meaning that half the tax get paid by Exxon et al. But all tax money still gets paid out to individuals.
    • elihu 5y ago
      I think resistance to a carbon tax is more complicated than that, at least in the U.S.. You've got a large and vocal minority that doesn't believe climate change is an issue in the first place. Of the people that are concerned about climate change, some are worried about the cost to themselves, and some are worried about the cost to others. I'm pretty well off (not wealthy, but middle-class) and I don't think a carbon tax would affect me much at all. But for some people it would be a big deal. I'm in favor of a carbon tax, but I understand the argument that it's recessive and is basically paid out disproportionally by the poor, because they spend a larger percentage of their income on gas and electricity. I think a carbon tax offset by a tax credit for lower-income taxpayers would be a reasonable option. I see cap-and-trade as the sort of arbitrarily-complicated system that Congress creates when they want to shake down an industry for campaign contributions. If it gets us less CO2 emissions I guess it's worth it, but still it's kind of gross.
• 08-15 5y ago
  How come? Conventional electricity plants also convert heat to electricity. That doesn't sound fundamentally different from your business. Was your input temperature too low? That would explain it. At low temperature differential, you have lower efficiency and need much bigger machinery for the same output. That said, fusion has a chance to be competitive, because the temperature will be higher. (Obviously, the thermodynamic limit is in the billions of Kelvin, but a practical power conversion system will operate in the range of 500-1000 Celsius.) But for the foreseeable future, it won't be competitive.
  • rfrey 5y ago
    Our heat sources were typically in the 500-600C range, with plant exhaust flows containing about 80-150MW of energy. Current tech can convert that with about 20% efficiency. Not at all like conventional electricity plants, the heat is already being created in industrial processes and is a waste product. We're familiar with delta-T and thermodynamics. Current off the shelf technology can easily hit half of the Carnot limit at most delta-Ts. That's not the point, the point is the "fuel" was free, and the price was "close" to existing sources as these things go (about 2x the price of natural gas) and even with a carbon market and climate mandates, it's impossible to get investment.
    • AnthonyMouse 5y ago
      If you go to an existing power market, there is generally already enough supply for the existing demand. And all of that supply is a sunk cost. The plants are already built. They're not going to get shut down unless the price falls below solely the operating cost. Building more capacity can cause the price to decline. In some cases by quite a lot. So nobody is going to want to finance it unless they see that either demand is about to increase or supply is about to decrease. Which is potentially true in the future. Electric cars will need more generation capacity. A carbon tax that causes existing fossil plants to shut would reduce existing supply. But it's also potentially not true. Maybe the demand for electric cars will be satisfied by an increase in rooftop solar and not an increase in utility-scale generation plants. We don't know when, or if, a carbon tax will happen in a given market. You guys also had a specific problem. If you're getting waste heat from natural gas plants, and then carbon prices increase to the point that people stop burning natural gas and switch to alternatives, you're not the ones absorbing that demand, you're the ones getting shut down. So you're in a different market position than would be the case for fusion after the introduction of a carbon tax.
• jhallenworld 5y ago
  Study this: https://www.lazard.com/perspective/levelized-cost-of-energy-levelized-cost-of-storage-and-levelized-cost-of-hydrogen/ https://www.lazard.com/perspective/levelized-cost-of-energy-... Ignoring storage: it makes no sense now to build anything but wind and solar. Only the marginal cost of gas is cheaper (meaning existing plants, not new ones). Including storage: conventional is still cheaper, but not by much (within a factor of 2): $81 for PV+storage vs. $44 for gas combined cycle. We should put more resources into storage now, fusion can wait.
  • adrianN 5y ago
    PV+storage is how many hours of storage? Storing enough power to last a night is just getting close to commercially viable afaik, but storing enough power to last a winter is still quite expensive.
    • myself248 5y ago
      The best storage is no storage at all, it is demand-response. Things like responsive appliances and EV chargers that can schedule their load rather than insisting that limitless power be available instantaneously. I don't care when the dishwasher runs as long as the dishes are clean by tomorrow, you know? Of course right now, putting the word "smart" on an appliance doesn't imply any of that, and the way it ends up implemented will probably be terrible and a half. But theoretically, demand-response could dramatically reduce the need for storage. I think it truly has a large role to play, but the folks releasing insecure internet-of-shit devices have a lot to answer for first.
      • pstrateman 5y ago
        There really aren't many things that can be off for significant periods of time without making them useless. Indeed I can't think of any that can be off for more than a day. Can you?
        • mikewave 5y ago
• Fordec 5y ago
  > We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. Was this Canada specific? A country with both very abundant native oil & gas and abundant hydro energy with nuclear power plants in place to boot. Not every country in the world has such abundant energy sources on tap.
  • rfrey 5y ago
    We tried to build in Europe and America as well; the economics are just hard. In the US there was very little market for carbon, which is why I said "even in Canada" since there is a regulated price for carbon here. The plants were mostly in Alberta, where NG is cheap but there is no hydro.
• zurfer 5y ago
  The question is not _if_ it will be cheaper, but _when_. Gas is a limited resource. We will eventually run out of it, the closer we get to that point the more expensive gas will become. But that point - without political intervention - can be many decades away.
• humaniania 5y ago
  Natural gas is only inexpensive because of fracking. With fracking in the USA at least the people involved can set up an LLC that dissolves after the well runs out. They are not required to disclose the contents of the fracking wastewater fluid. It gets pumped back down underground where it could dissipate into the rest of the water system. These people claim that it's safe for decades when our computer models can't predict the weather accurately next week. In California now they're using fracking wastewater on crops because of the water shortages. Without disclosing what's in it. And not testing for if that stuff ends up in the food. These people are using loopholes to take the profits now and leave society with the bills for cleanup and the health consequences. That isn't sustainable or IMO fair or just. If the real cost of fossil fuels was clear up front they would not make sense. https://www.latimes.com/local/california/la-me-drought-oil-water-20150503-story.html https://www.latimes.com/local/california/la-me-drought-oil-w...
  • whatshisface 5y ago
    >These people claim that it's safe for decades when our computer models can't predict the weather accurately next week. The models may or may not be accurate but they have nothing to do with predicting the weather. There isn't any weather underground... It's all slow diffusion and buoyancy. A better starting place might be asking where the model inputs come from.
    • mcguire 5y ago
      Doesn't "diffusion and buoyancy" technically describe the weather, too?
      • whatshisface 5y ago
        Diffusion and buoyancy are indeed both things about the weather, but the nonlinearity of the navier-stokes equation stems from the ability of convection to transport momentum. Fluids moving through rocks can't go fast enough for that to happen.
    • phillc73 5y ago
• Scarblac 5y ago
  Natural gas costs don't include the external costs like climate change, so it looks better than it is. We have to stop using fossil fuel soon to prevent really catastrophic changes, so then other sources are needed.
  • jack_riminton 5y ago
    Exactly. The costs are much more than economic. It's the Tragedy of the Commons https://en.wikipedia.org/wiki/Tragedy_of_the_commons https://en.wikipedia.org/wiki/Tragedy_of_the_commons
• stormbrew 5y ago
  > We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. Worth noting that the current plan is for the minumum carbon tax in canada to increase by $15/tonne/yr until 2035, so the question might be more when will it reach a break even point? Seems like you'd want to be positioned for that.
  • wussboy 5y ago
    That kind of forward thinking is unfortunately rare.
  • rfrey 5y ago
    That was our company thesis, that carbon was systematically underpriced and we wanted to amass a portfolio of carbon credits before that was corrected. But you still need to provide project investors with a competitive ROI if you want to build the thing.
• cletus 5y ago
  > How is fusion different? It's not but people don't seem to realize this or maybe just don't want to think about it. Spending $100B to produce 1GW of power (made up numbers) is not an economical source of power. So hydrogen being free (deuterium and tritium are essentially free; Helium isotopes are more complicated) is irrelevant until the capital cost of the plane is much, much lower. And even then you still have to deal with these significant issues: - Neutron embrittlement of the container; - Energy loss from the chamber from neutrons; and - Containment. The plasma is essentially an extremely high temperature turbulent fluid. Because of the turbulence and the super-high temperatures containment is likely to remain a significant issue. I hope fusion becomes commercially viable and economical but I'm just not convinced (yet) that that will ever be the case. It certainly won't be ITER even with tens of billions spent on it. People get caught up on the fact that stars do fusion without considering what's different. To summarize: - Energy loss from neutrons is essentially a non-issue because of gravity and just the size of stars. To put this in context, it's estimated that photons created at the Sun's core take ~30,000 years to escape; - Stars are relatively inefficient with their fuel. IIRC the Sun converts ~4.5M tons of matter into energy every second. It sounds like a lot but that's a tiny fraction of the Sun's mass (~10^30 kg). That's because hydrogen atoms are so unlikely to fuse and they go through several intermediate states before that happens. Fusion in the lab already produces many more fusion reactions per unit mass than stars do. I firmly believe that space-based solar power collection is our most likely future. EDIT: corrected "photons"
  • marktangotango 5y ago
    > I firmly believe that space-based solar power collection is our most likely future. Isn't this the same capital expenditure analysis your post starts with though? How many billions does it cost to get the solar panels to orbit in sufficient quantity? And ground stations to receive the energy beams (microwave presumably). This is where Musk/Spacex push for cheap kg to orbit really matter. Even in the 70's they worked out that mining the moon for raw materials to build space based solar was much more economical.
    • cletus 5y ago
      So during the Space Shuttle (and earlier) era I believe the cost of getting payloads to LEO was $20-50k/kg. Currently with Falcon 9 it's gone down to ~$1000/kg. I imagine this will continue to get cheaper with further reuse and Starship. But we really need to get down to <$10/kg. Thing is, that's entirely achievable. I believe the ultimate future here will be orbital rings [1]. Space elevators get a lot more attention and they really shouldn't because they're a lot less achievable and they require materials we haven't invented yet (to resist the centrifugal force). Imagine being able to take a cable car into orbit. That's what orbital rings promise and you need little more than copper wire and stainless steel. Not only would this bootstrap colonization of space but you can simply attach collectors to the ring itself and run the power down a cable to the ground so you don't even need to suffer the power loss from wireless transmission (which, for the record, is a practical method still). [1]: https://www.youtube.com/watch?v=LMbI6sk-62E https://www.youtube.com/watch?v=LMbI6sk-62E
• hpcjoe 5y ago
  Very likely, each fusion plant (if they ever exist) would require, ironically, a fission plant next door to provide the power required for the magnets. The magnets, and wiring won't be cheap. The power delivery and control won't be cheap. I'm not sure how this would be amortized into the cost of the power, without making it 2-3x (or more) more expensive than alternatives. We can build, and we need, nuclear plants now, to be able to generate cheap/plentiful electric power. And if we don't we're basically going to have to push the brakes on EV deployment. Or light up more NG/Oil plants to provide the power for those.
  • thehappypm 5y ago
    This approach doesn't use magnets.
  • epistasis 5y ago
    > We can build, and we need, nuclear plants now, to be able to generate cheap/plentiful electric power. And if we don't we're basically going to have to push the brakes on EV deployment. Or light up more NG/Oil plants to provide the power for those. The real power generation tech here will be wind and solar, not nuclear. We can build lots and lots and lots of it, easily and cheaply. And using it to charge vehicle batteries doesn't even require intermediate storage. Even construction powerhouses like China are deploying more than an order of magnitude more renewables than nuclear, because renewables will be the backbone of any future grid. Nuclear isn't getting any cheaper, yet wind solar and batteries are on exponentially decreasing cost curves. People on HN are far better able to understand exponential technology advancement than people in the energy industries. And hopefully we can all see how renewables plus batteries is going to make nuclear obsolete.
    • elihu 5y ago
      I wish there was more interest in electrifying our major roads and freeways (i.e. allowing cars to charge while they're moving) in part to reduce the necessity of hauling giant batteries around everywhere, but also to shift EV power use from mostly-nighttime to mostly-daytime when more solar power is available. Another option is to get some high-capacity high-voltage DC lines connecting continents so that countries around the world can sell power during the day and buy it at night. We can keep the fossil fuel plants around as emergency backup. At this point, though, we're a long way even from being able to shut off the fossil fuel plants during the day while the sun is shining.
• Animats 5y ago
  Doing something with low-grade heat is hard and often futile. E = (Th-Tc)/Th. Look at a gas turbine. There's a succession of turbine wheels, getting larger towards the end. Each is running off the exhaust of the previous wheel, at a lower pressure. If you added another, larger, turbine wheel at the end, you'd get a little more energy out, at higher machine cost. The turbine ends where adding another wheel is not cost-effective. Starting from the exhaust at that point means you're competing with turbine manufacturers who decided they'd reached the economic limit. That's fighting the Second Law of Thermodynamics. The hot end temperature for fusion systems is quite high. Tens of millions of degrees at the plasma. Fusion has lots of problems, but thermodynamic efficiency is not one of them. The dream is that somehow that high temperature plasma from the fusion reaction is run through a hollow coil to generate power by magnetohydrodynamics. No turbine required. Somehow. Maybe someday. No clue how to do this yet.
  • rfrey 5y ago
    Exhaust from a gas turbine for a pipeline compression station is around 600C at about 95kg/second. That flow contains about 100MW of heat energy, which can be captured with Organic Rankine Cycle (like steam cycle, but using organic fluids like cyclopentane as a working fluid to better match the thermodynamics) about 20% of that can be converted to electricity. This is off-the-shelf tech. The problem isn't the technology, it is the economics.
    • lazide 5y ago
      The parent was pointing out that the economics are also a fundamental limit of the technology/physics. If you can do a lot of work with expensive machines to get 20MW from that plant, but you can also do less work and spend less money getting an extra 20MW by burning some cheap primary fuel (with higher quality heat/aka a bigger delta), then they’re just going to burn more primary fuel. It’s a bit silly to do it any other way (barring legislation or market pressures or whatever) if you care about the amount of energy you are getting for the money you are paying. And that is a fundamental issue, as reclaiming energy from secondary heat is always going to be less ‘nice’ than from the primary fuel. If you can do it easily enough that it doesn’t add a lot of extra cost, then chances are the primary turbine/power system could be built efficiently enough to not throw that waste heat out the back in the first place. They do so because the math doesn’t check out generally.
• sandGorgon 5y ago
  true this. In fact - im wondering why molten salt reactors which the US innovated almost 60 years back where not pursued. Thorium is plentiful and cheap - and Terrapower seems to have already productized cheap miniaturized MSRs.
• thehappypm 5y ago
  In addition to being a large project to set up geothermal, they don't generally produce a lot of power. The largest deployment in the world is in California (The Geysers) and spans ~20 separate units, and each unit on average produces around 100 MW. A gas plant produces around 500 MW, and a nuclear plant about 1 GW.
• thescriptkiddie 5y ago
  The unpopular truth is that fossil fuels are far too cheap. If the negative externalities were priced in, they would be at least twice as expensive, perhaps as much as ten times.
  • xondono 5y ago
    > If the negative externalities were priced in they would be at least twice as expensive Quotation needed
    • piva00 5y ago
      Here's a source for a recent meta-analysis of hidden costs of fossil fuels [1]. Findings on the abstract already corroborate the parent comment. [1] "The hidden costs of energy and mobility: A global meta-analysis and research synthesis of electricity and transport externalities" - https://www.sciencedirect.com/science/article/pii/S2214629620304606 https://www.sciencedirect.com/science/article/pii/S221462962...
      • xondono 5y ago
        The problem with this type of study is that it can by definition only cover the known externalities, but most of the price of externalities is far into the future. This means that the real margin of error is huge (and unknowable at this time).
        • akimball 5y ago
          Also it misprices tail risk, marking it to zero
    • pdoege 5y ago
      For coal in the USA the stated cost for MWh in 2010 was $41. The external cost was $58. This does not include for implicit and explicit subsidies. Including those would make the external costs higher. The numbers change by country, time, energy source, and etc. so asking for a quotation is a bit of a fishing expedition. See Tables 1 and 2 at: https://www.climateadvisers.com/wp-content/uploads/2014/01/2011-10-The-Social-Cost-of-Coal.pdf https://www.climateadvisers.com/wp-content/uploads/2014/01/2... If you have the spare time to read 507 pages of support, please see: https://www.nap.edu/download/12794 https://www.nap.edu/download/12794
• lazide 5y ago
  There are a couple potential answers to your question. 1) ‘make it up in volume’ - part of the reason for the relatively high capital cost of the technologies you are describing, is they don’t scale well from a one-off design or manufacture vs amount of energy produced perspective. Geothermal plants require significant amounts of ‘actually sticking a very long pipe into unstable ground’ which can’t be effectively economy-of-scaled away to be cheaper. There are also only a relatively small number of locations with the right factors to make it worthwhile. Presumably the waste heat systems you are referring to require custom fitting to the plant in some way, and there are also not a huge number of places with sufficient waste heat to make it worthwhile. Both of these techs are in the sub-gigawatt (often sub-hundred megawatt) range. That adds a lot of friction, thinking, and site/location specific ness for a relatively small amount of power. IN THEORY fusion can produce massive (giggawatt) power anywhere, and there is no reason you couldn’t make one for every neighborhood if you wanted. Please be aware that practically speaking this seems to be a fantasy. 2) most people don’t/can’t understand the physics, so it is really easy to project impossible benefits onto it that will never play out in real life, and sound plausible while doing so. This makes it easier to sell to politicians in particular. 3) IN THEORY because of these factors, whoever comes up with fusion first is going to take over the world (either commercially or politically), so there is a lot of pressure to not be #2 there. This outweighs things like pesky market dynamics and concrete profit margins. 4) also, since no one has a prototype or design for a reactor that could plausibly actually be a viable commercial reactor, no one has the ability to sit down and figure out if the math works or not. This is all still research reactor space.
• ChuckMcM 5y ago
  I could cite you things like this: (https://www.osti.gov/biblio/6276900 https://www.osti.gov/biblio/6276900) but they will likely be buzzword soup. The simplest explanation is that the fusion reactor's energy output is the _primary_ heat source for a heat engine like a steam turbine. It sounded from your description that your company was targeting so called "waste" heat, which is a lower grade of heat (smaller delta between ambient so a smaller temperature differential to work with). There are limits to the efficiency of being able to convert heat into some other form of energy (kinetic, chemical, electric, Etc.) because that is how the universe works sadly. That said, when you have a very large heat differential, as you do from fusion or fission reactions, converting even a small percentage of that can be a net win in terms of production. So fusion is different in that it can take a small amount of widely available "fuel" and release a large amount of energy by "burning" it (in actuality fusing it into a new element, but the effect is that the original fuel is no longer available for use) and then using that heat to run heat engines that are producing electricity. The waste products are the fused result and heat in the form of highly energetic alpha particles.
  • AlbertCory 5y ago
    Skin in the game [1]. OP has actually done it ("CTO of a company providing heat-to-electricity plants"). Have you? Or you just read about it? [1] https://www.amazon.com/Skin-Game-Hidden-Asymmetries-Daily-ebook/dp/B075HYVP7C/ref=sr_1_1 https://www.amazon.com/Skin-Game-Hidden-Asymmetries-Daily-eb...?
    • hellohntoday 5y ago
      OP doesn't bring up the different temperature and pressure differential of heat sources. That's a huge red flag. For all we know the CTO role at that company was entirely focused on keeping the staff laptops running and is largely disconnected from the fundamentals of heat to electricity generation. Why the hell would she (or he) ask here when (s)he has current or former colleagues in the industry to ask. My BS detector went off immediately.
      • tuatoru 5y ago
• mraison 5y ago
  It's hard to compare a fusion plant and a geothermal plant if we don't know how much energy a single fusion plant could produce. Are there any estimates on that?
  • cbtacy 5y ago
    https://www.lockheedmartin.com/en-us/products/compact-fusion.html https://www.lockheedmartin.com/en-us/products/compact-fusion... "A reactor small enough to fit on a truck could provide enough power for a small city of up to 100,000 people."
    • pfdietz 5y ago
      After 2014 they expanded the volume of that putative reactor by a factor of 100. Also, fitting on a truck was always assuming no neutron absorbing blankets (which have to be ~1 meter thick.)
• dibujante 5y ago
  Bingo.
• Ericson2314 5y ago
  Supply doesn't create it's own demand. This is plain social failing you're describing. You ask whether it will happen to fusion, I would argue it has already been happening to both for quite some time. Just as starter motors are needed to stat ICEs, so new sorts of power generation start as unprofitable, and end as essential.
• SuoDuanDao 5y ago
  I don't think nuclear power - fission or fusion - can ever be profitable on a capital return basis. They're the best bang for your buck if the cost of capital is zero and among the worst if it's greater than zero. Nuclear physicists and engineers are smart enough that I think they could understand this problem if they spent a weekend grappling with it, but they're so specialised in their very difficult discipline that they never spend that one weekend.
  • pfdietz 5y ago
    There's also Upton Sinclair's famous comment: "It is difficult to get a man to understand something, when his salary depends upon his not understanding it."
• NineStarPoint 5y ago
  Fusion is different in that the math scales well with the size of the fusion plant you create (and also the power of the magnets you have access to). If it's technologically feasible to create a large enough fusion plant, it starts to be able to create ludicrous quantities of electricity compared to things like geothermal that have much harder limits. Of course, "technologically feasible" is doing a lot of heavy lifting, but it is in the realm of theoretical possibility for a large scale fusion plant to be cost effective.
  • pfdietz 5y ago
    Fusion has diseconomies of scale. The larger a fusion reactor is, the worse its volumetric power density becomes.
• onion2k 5y ago
  Simple solution - nationalize energy production.
  • thow-58d4e8b 5y ago
    Proposing nationalization is akin to blasphemy nowadays - way outside of Overton window. But I haven't really heard any good arguments or benefits of electricity production and distribution being private. On the other hand, there are a lot of good arguments in favor of state ownership - matter of national security, need for redundancy instead of efficiency, it's a commodity and a basic necessity, low margins, large scale leads to financing issues for corporations, chicken-egg problems that state is better at dealing with, the domain is primarily about engineering challenges with branding and management having very limited impact, simple supply chains, cost-cutting may lead to disastrous consequences, etc...
• ivix 5y ago
  The cost of a fusion plant will be a small fraction of the cost of a fission plant, where the extreme safety requirements makes it expensive. People are now testing fusion in small regular industrial facilities.
  • pfdietz 5y ago
    Engineering studies over the years have come to the opposite conclusion. Fusion reactors will be much larger than and much more complex than fission reactors, and hence much more expensive.
• chmsky00 5y ago
  Perhaps the cost to be concerned with is not fiat currency but more literal. The up front costs could wipe out the routine costs and maybe we could also dispose of the “ make money selling blades not handles” monopoly fossil fuel monopolies rely on for political relevance. Infinitely big little numbers let economists iterate forever in whatever direction they want. Physical reality has constraints their academic models omit. We need to redefine the perimeter not iterate within the area of a well known boundary. Who cares how much it costs aristocrats in profits if the result ends up what is believed possible? I don’t have to believe any given solution or CEO is owed a market.
• pipodeclown 5y ago
  Fusion is not going to be commercially viable anytime soon but that's not the point. Whether how and to what we transition is a political choice, if fossil fuels are too cheap for renewable to compete, you tax carbon fuels more. Renewables mostly everybody is ok with however have the problem that don't produce power consistently and on demand, that's where nuclear power comes in to fill that gap and hopefully in the future fusion. If we dislike the nuclear waste problem enough, we'll have to pay up to make fusion a financially viable alternative.
• porphyra 5y ago
  Generating energy from the difference between extremely hot and slightly hot is cheap and efficient using turbines. Going from slightly hot to cold, as in the case of geothermal and capturing residual heat in the stack of a natural gas plant, is thermodynamically inefficient and quite expensive. Since fusion energy is extremely hot, it is efficient. Other sources of "extremely hot" include: combustion (typically from fossil fuels) and solar thermal.
• pfdietz 5y ago
  DT fusion is not different, and is unlikely to be competitive. This was understood decades ago. http://orcutt.net/weblog/wp-content/uploads/2015/08/The-Trouble-With-Fusion_MIT_Tech_Review_1983.pdf http://orcutt.net/weblog/wp-content/uploads/2015/08/The-Trou...
• asdfge4drg 5y ago
  for someone who worked in this area, you have an unbelievably short term view. humanity either has fusion reactors or it doesn't. imagine what we can do with them, the spacecraft we can build, submarine cities, one in every home. Mars, Europa. It's not where we'll be 10 years after we do it, but 100 years, 500 years. To get there, we've got to step forward now.
  • cbtacy 5y ago
    Well said and thank you (speaking as one who also has worked in this area).
  • pfdietz 5y ago
    DT fusion reactors are useless for spacecraft. They don't do anything that fission reactors couldn't do better, more cheaply, and much more compactly. Open Brayton cycle fission reactors would be outstanding on Titan, with all that cold gas to compress and reexpand after warming to quite moderate temperature.
• fsckboy 5y ago
  > high-heat plants like natural gas turbines. The "fuel" was heat going up the stack if you're burning natural gas to run a gas turbine, a substantial part of the energy has being drawn off by the turbine, so the "waste heat" that you are trying to scavenge has much lowered potential energy to capture.
• ummonk 5y ago
  Burning natural gas creates heat, which is used to drive turbines and generate power. I see no reason why the heat to electricity side of a fusion power plant would be any more expensive, assuming we manage to bootstrap economy of scale.
• xyzzyz 5y ago
  Why couldn't you compete? Where was the expense in your system? Guessing, it was mostly the equipment to extract the waste heat, wasn't it? What if that equipment was 10 times cheaper, could you compete then? If you there was large demand for your system, you could produce your equipment in huge volumes, and bring down unit costs enormously, no?