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Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

imperial.ac.uk

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Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#191

Post by AnthonyMouse »

rfrey wrote: post #118
08-15 wrote: post #76

Earlier quoted context omitted.

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 therm…

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…

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.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#192

Post by Andrew_nenakhov »

einpoklum wrote: post #114
Andrew_nenakhov wrote: post #90

Earlier quoted context omitted.

"We should put more resources into breeding faster horses now, internal combustion can wait." - someone in late 19 century.

Well, if we'd have gone down that road, plus strong environmental awareness, maybe the Earth wouldn't be warming up so badly right now, and the oceans wouldn't have islands of plastic (= oil) waste. Now, sure, we wouldn't have enjoyed some of the benefits of car technology, but - public transport (esp. trains) makes up for a lot of that. OTOH, public transport pollutes too.

Had we gone down this road, we'd have a thick layer of manure covering everything. Living creatures are a source of CO2 too, and a big one. Look up for a share of greenhouse gases coming form agriculture. Had we used faster horses, that volume of emissions would be effectively doubled or tripled.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#194

Post by Robotbeat »

jhallenworld wrote: post #84
rfrey wrote: post #61

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. We financed and built them off high-heat plants like natural gas turbines. The "fuel" was heat going up the stack - so it was essentially free. We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. G…

Study this: 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 n…

Why should we wait for fusion? We can and should do both, and fusion also benefits from storage. Fusion and fission help northern countries in particular as they actually produce MORE energy during the dark, cold months.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#195

Post by Robotbeat »

dragontamer wrote: post #104
Andrew_nenakhov wrote: post #90

Earlier quoted context omitted.

"We should put more resources into breeding faster horses now, internal combustion can wait." - someone in late 19 century.

The benefits of a car were immediately obvious as soon as supply lines were considered. Feed for horses was something like 30% of all deliveries in a horse-based supply chain. Railroads run off of coal, but steam-engines were huge. ICE engines were miniature engines that also ran off of a fuel source (eventually settling upon oil, but many different fuel sources were considered in those early days, including electric…

No, horse breeders argued the supply lines favored horses as horses could be fed by unlimited biofuels instead of limited fossil fuels. Of course, there was a difference in scale, but it’s just false to claim there weren’t major naysayers about automobiles from the horse industry.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#196

Post by Robotbeat »

scoopertrooper wrote: post #143
Andrew_nenakhov wrote: post #90

Earlier quoted context omitted.

"We should put more resources into breeding faster horses now, internal combustion can wait." - someone in late 19 century.

Your analogy falls flat because we're still decades away from a functional fusion power plant. "Why breed faster horses now when maybe my grandchildren will get to zoom around in cars?"

We aren’t. MIT’s SPARC Tokamak design could be ready for commercialization by a decade. Less time than completing a high speed rail project in the US.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#197

Post by myself248 »

mikewave wrote: post #172
myself248 wrote: post #108

Earlier quoted context omitted.

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 i…

> I don't care when the dishwasher runs as long as the dishes are clean by tomorrow, you know? You can already accomplish 95% of this now with any dishwasher made within the last 20 years that has a delay timer on it. Just load it up and tell it to run in 6 hours and then go to bed. I don't want some 3rd party company driving a huge team of middlemen sucking up a gigantic pile of data in order to determine when it mi…

I think we agree more than we disagree. An overnight timer is ideal right now while most base-load comes from coal and nuclear, and power is cheapest at night.

But as we move past combustion (I'm in Michigan and the amount of coal we burn for power is absolutely shameful) and into more solar, it's less predictable. I can't set a timer that knows when the sky will be cloudy.

This is why I'm so excited to see EVSEs that take data from PV inverters and have a "PV surplus only" mode, where the car is charged only when the sun shines, without ever importing grid power. Modulating 30kW of load is just as good as 30kW of storage, but costs nothing but a few lines of code.

And yeah, networks and middlemen can suck it. Keeping it local is always better.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#198

Post by thehappypm »

I'm struggling to understand what exactly happens. The deuterium and tritium mixture is hydrogen -- so it is a gas? So is it in some sort of gas-containing container, that also lets laser light through -- probably some kind of glass container? What kind of glass container can survive having this much energy pumped through it, and such a hot gas inside it?

https://en.wikipedia.org/wiki/Fusion_ignition

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#199

Post by rfrey »

Animats wrote: post #163
rfrey wrote: post #61

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. We financed and built them off high-heat plants like natural gas turbines. The "fuel" was heat going up the stack - so it was essentially free. We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. G…

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…

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.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#200

Post by Robotbeat »

eldaisfish wrote: post #169
jhallenworld wrote: post #84

Earlier quoted context omitted.

Study this: 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 n…

Lazard do not factor in the cost of accommodating the vagaries of wind and solar into these figures. As just one example - when the wind turbines aren’t running, your lights are still on. That power comes from somewhere and that somewhere has a cost to keep it available. That cost is passed on to electricity consumers but not the source of the problem - wind and solar generators.

Yeah, a better option is to use capital costs and input them into https://model.energy
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