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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

#291
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…

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…

> In California now they're using fracking wastewater on crops

That's not what your linked article says. The article says treated wastewater is being used. That being said, it appears to be in dispute if the water is treated enough, with the water district claiming that it is and an environmental group claiming its not.

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

#292

Earlier quoted context omitted.

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…

I wonder if it’s possible to create air conditioning that generates electricity. It seems like you’re removing energy from the air.

Think of it like water flowing down a hill. The heat is in your room because it flowed down to a cooler space with less energy, just like the water flowed down to a space with less potential energy. Moving that heat back to a higher energy area, back outside, is the same as pumping the water back up a hill. It always takes more than one unit of energy to move one unit of energy back “up”. You can only capture energy if it’s moving “down”.

You might enjoy a physics course, especially if you enjoy calculus, although an entry level course won’t require it.

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

#293
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…

> 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.

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.

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

#294

Earlier quoted context omitted.

I could cite you things like this: ( 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 tempe…

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-eb... ?

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.

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

#295

Earlier quoted context omitted.

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.

People thought fossil fuels were a finite resource back then?

I mean, I wouldn't be surprised if someone thought that, but given the frequency with which oil was being discovered, it seems reasonable that people would have assumed it to be effectively unlimited.

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

#296

Earlier quoted context omitted.

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.

Call me with the second and third commercial reactors are completed. That's when we'll have an idea of the real world viability, including how to scale and deal with production concerns.

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

#297
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…

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.

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

#298

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…

Yes, but bulk of the demand is heat and industry, so you're quickly back to having to build a lot of "storage" in the form of buildings with high thermal inertia and spare capacity for production, so that you can keep the high energy plants idle at inconvenient times. Hard to say if that is more efficient than building actual energy storage. Every little helps I guess, but getting people not to shower on cloudy days…

Heat is fairly trivially stored for months on a mass scale, check out Polar-night Energy's system - basically, you heat up (usually with just resistive heating) a bunch of sand in a 40metre-wide insulated cylinder, and when you want to use that heat you use fans to blow air through ducts that are surrounded by the sand.

The amazing thing is that every single part of the tech is old and boring - resistive heating is literally as old as electricity, electric fans and ducting are trivial, heating sand is basically impossible to screw up, etc etc.

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

#299
post #146
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…

> 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 t…

> 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.

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

#300
post #250

Earlier quoted context omitted.

> If the negative externalities were priced in they would be at least twice as expensive Quotation needed

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/S221462962...

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).
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