Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

imperial.ac.uk

Post reply on HN
Print view View original

321–330 of 494 posts

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

#321

Post by pipodeclown »

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…

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.

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

#322

Post by cletus »

marktangotango wrote: post #299
cletus wrote: post #146

Earlier quoted context omitted.

> 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 worke…

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 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

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

#323

Post by learc83 »

meltedcapacitor wrote: post #180
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…

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…

You could just implement enough surge pricing that people/companies work around peak times on their own and build their own storage.

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

#325

Post by xondono »

nomel wrote: post #276
xondono wrote: post #236

Earlier quoted context omitted.

My argument doesn’t care who’s pocket is funding the renewables. As a society, every extra dollar spent on pricier energy is an extra dollar that can’t go to social programs, or to new start up, or anywhere.

Many would claim that every extra dollar spent on renewables is reducing the environmental debt that we’ve accumulated, that we have to will pay for, with very real dollars, since we’ve subsidize our energy cost with future remediation costs. I think there’s some in-between here.

You can explain or justify the costs however you like. That's not the issue. I'm not making any claims as to the suitability of spending more or less into renewables, just pointing the obvious but often forgotten consequence, that every dollar spent here is a dollar you can't spend in another place.

Swapping to renewables at once would have an impact that can very easily overshadow any remediation costs. Even tiny cost increases now will produce vast difference 100 years forward due to compounding.

Just as a thought experiment, if the costs of switching to renewable energy are >0.72% of GDP, and the remedial costs are around 18T$ (in today's money) in 100 years, you're still better off not switching to renewables.

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

#326

Post by Mewit »

humaniania wrote: post #213
Mewit wrote: post #181

Earlier quoted context omitted.

I don't think it is accurate to say it "dissipates into the rest of the water system". Typically the hydrocarbon formations being fracked are thousands of feet below the water table, separated by thousands of feet of impermeable shale. It's the same, or more so, for disposal zones where the frack fluid that flows back is injected. For the fluid to mix with a potable aquifer, it would have to leak within a wellbore. T…

"impermeable" until there's an earthquake caused by fracking and things shift deep underground where nobody can monitor or track what is happening? Seems exceptionally short sighted to me. https://www.usgs.gov/faqs/does-fracking-cause-earthquakes

I think it's best to look at the options through a risk matrix. Is it possible that an earthquake is generated by fracking that is big enough to geologically connect a hydrocarbon formation with a surface aquifer thousands of feet above it? I suppose, but I think it is very unlikely. I don't think there are any cases of that on record, and wells have been fracked in the US for many decades (although not as frequently as recently). What is the consequence of that happening? A community (likely a rural community) loses potable drinking water. I would say that is a low probability of a medium impact event.

The calculation is going to change if there is a higher probability of drinking water contamination for whatever reason, or if more people live in the area and would be impacted by an event, just as the risk matrix is different building a nuclear power plant in France compared to building one on the Japanese coastline. Of course every jurisdiction makes its own decisions, as is their right, but the consequence of always taking the least risky option can leave a country in a tough situation when those options don't cover their energy needs, like in Germany (and elsewhere in Europe) right now.

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

#327

Post by porphyra »

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…

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.

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

#328

Post by xondono »

8note wrote: post #272
xondono wrote: post #236

Earlier quoted context omitted.

My argument doesn’t care who’s pocket is funding the renewables. As a society, every extra dollar spent on pricier energy is an extra dollar that can’t go to social programs, or to new start up, or anywhere.

Every extra dollar saved on cheaper energy actually goes to lining some billionaire's pockets in some untaxed hole. And then eventually the people who would benefit from said social program will instead have to pay back a climate debt in the future.

If we are going to just made up magic pockets where infinite money lies, then we can justify whatever we please.

The point of my comment is that it doesn't matter where the money is. Even if you were to pay it through massive taxes to the rich (assume no loopholes, no funny accounting tricks possible), the ones picking up the tab are the poor people of the future, because even if all millionaires are evil movie villains, taking their money will hurt growth, and growth compounds. Reducing growth now can be a catastrophe when compounded over 100, 200, 500 years.

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

#330

Post by Mewit »

humaniania wrote: post #217
Mewit wrote: post #181

Earlier quoted context omitted.

I don't think it is accurate to say it "dissipates into the rest of the water system". Typically the hydrocarbon formations being fracked are thousands of feet below the water table, separated by thousands of feet of impermeable shale. It's the same, or more so, for disposal zones where the frack fluid that flows back is injected. For the fluid to mix with a potable aquifer, it would have to leak within a wellbore. T…

Also maybe read the entire article on using fracking wastewater on crops: Until now, government authorities have only required limited testing of recycled irrigation water, checking for naturally occurring toxins such as salts and arsenic, using decades-old monitoring standards. They haven’t screened for the range of chemicals used in modern oil production. No one knows whether nuts, citrus or other crops grown with…

I don't know anything about this, but contamination seems plausible, as you say, and it would probably make sense for California to update its regulations to make sure the crops grown with this water are safe for consumption.

I think this is a pretty unusual situation. As far as I know, most spent frack fluid is reused in oilfield operations or disposed of in deep disposal wells.

Post reply on HN