One objective is a Q value of greater than 10 for a moment. And a steady Q value of 5. Source: https://en.wikipedia.org/wiki/ITER#Objectives
Maintain a fusion pulse for up to 8 minutes What does this mean?
Tokamak-style reactors like ITER rely on a rapidly-changing magnetic field to induce an electric current in the plasma, for stability of the plasma. The magnet that provides this rapidly-changing field (the 'central solenoid') can't keep increasing in field strength indefinitely -- so there's a time limit to the life of the plasma. There are other ways to supplement the current in the plasma, which can help extend the life of the plasma indefinitely.
Looking at stories like this, you need to realize how far out of the running this technology is.
The power density of ITER (gross fusion power of the reactor divided by the volume of the reactor, not just the volume of the plasma) is 50 kW/m^3. This is horribly low, about 1/400th the power density of a PWR reactor vessel.
The power/$ is also horribly bad. The cost is going to have to come down by two orders of magnitude to start being competitive.
Fusion is an example of sunk cost thinking. The only reason we're working on it is because we had been. A clean sheet energy strategy would put very little resources into fusion.
That’s all well and good if you reach stability below a level that is sustainable. We aren’t going to be anywhere near that from an environmental point of view.
And whybdo you believe that? We will never surpass 12 billion by most estimates. Where is the sustainability point?
The sustainability point is where we can survive as a global population without destroying and depleting the resources of the planet. What point that is exactly is impossible to say because we have never done proper research (as far as I know), but what we can say for sure is that global population passed that point a long time ago. Mass extinction, overfished oceans, deforestation, saturation of the environment with chemical pollutants (not limited to carbon), soil degradation from nitrogen saturation (and the nitrogen runoff that has created massive dead zones in our oceans and other waterways) - the ways we have destroyed our planet in order to sustain our overpopulation go on and on. As evidenced by the downvotes to my original comment, the unfortunate reality is that many, if not most, refuse to accept reality out of religious-like delusion. Some worship at the altar of technology, some believe that its immoral to see a moderation of human population, some worship at actual religious altars and believe its blasphemy to even discuss the issue, and some blindly accept conventional wisdom that we need an ever-increasing population in order to sustain the economic ponzi scheme that modern society rests on (despite the fact that we have a massive supply of surplus labor).
I'm also a fusion power fanboy but >nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone This is just not true, there's no way you can say this. Solar costs are going down massively. Hydro is dirt cheap already. So renewables can absolutely be part of an energetic transition in the near future, while fusion is a…
Hydro is actually pretty bad in terms of big safety incidents (Banqiao: 171000 dead, Machchu: 5000 dead, South Fork: 2208 dead) and solar/wind have trouble beating nuclear on metrics like death/watt because you need lots of infrastructure per watt. Picture a few large cities with contractors running around every roof tending to solar panels and compare to a few experts at a single nuclear power plant. For the contrac…
> olar/wind have trouble beating nuclear on metrics like death/watt because you need lots of infrastructure per watt.
There were some studies claiming nuclear has lower deaths/kWh, but as I recall they (1) used old numbers for wind that do not reflect current safety figures, (2) assumed solar was rooftop instead of utility-scale which is now dominating installations (because it is so much cheaper), and (3) ignored deaths from uranium mining, which is where most of the release of radioactive material is in the fuel cycle.
I'm also a fusion power fanboy but >nuclear power is the only realistic way to solve the looming energy crisis of the 21st century while still maintaining the same standard of living for everyone This is just not true, there's no way you can say this. Solar costs are going down massively. Hydro is dirt cheap already. So renewables can absolutely be part of an energetic transition in the near future, while fusion is a…
>This is just not true, there's no way you can say this. Solar costs are going down massively. Hydro is dirt cheap already. So renewables can absolutely be part of an energetic transition in the near future, while fusion is at best many decades away. So while I think fusion energy has the potential to transform energy generation, and by extent everything about our life, it's wrong to assume renewables aren't probably…
> We need nuclear to meet baseload because the storage requirements (for PV particularly, by far the largest renewable) would be absurd without it.
This is not true. With a properly designed solar/wind/battery/hydrogen system, a steady stream of power can be delivered more cheaply than what you could get from a new nuclear reactor.
This wasn't true even ten years ago, but it's true now, and many (such as yourself) have not updated your priors.
Important distinction here: nobody actually cares or wants power that is baseload. In some cases it can actually be a bad thing. The property you really want is “dispatchable”. There when you want it. Not when you don’t.
>nobody actually cares or wants power that is baseload. That doesn't make sense. At all hours of the day there is some demand on the grid: https://www.eia.gov/todayinenergy/detail.php?id=42915 If you only have to store for the fluctuations vs. having to store all night you end up with massively less storage. Electric cars won't do it either. There are less than 300 million registered vehicles in the US and a car batt…
Go there and model (with real historical weather data) how much a solar/wind/battery/hydrogen system would cost to deliver steady power. Then compare against new nuclear. Sorry, nuclear.
(The hydrogen part is essential in some places, like northern Europe, and its impact is not fully appreciated by many nuclear fans.)
Is it really clear the fusion power, even if it's achieved, will actually be cheap enough to use? Sure, the fuel is almost free, but the fuel for solar, wind, and hydroelectric power is also free and that doesn't make them cheap. If we're not worried about cost, we could build enormous batteries using existing technology and use solar and wind to power everything. Fusion has to be cheaper than that, and judging by th…
Well, fusion has the benefit of having much lower operating costs. Violent terminations, quench events, and tritium containment breaches are serious concerns, but a risk assessment of a fusion power plant would give a much cozier feeling than a risk assessment of a fission power plant. The neutron activated materials are safe after a century and there is not much of it. All of the cost in a fusion plant sits on manuf…
Fusion will likely have much MUCH higher operating cost. Fusion reactors are fearsomely complex things that will be too radioactive for hands on maintenance. They will be operating at much higher levels of radiation damage and thermal stress than fission reactors. That all adds up to a reliability and maintainability nightmare. The fuel being cheap doesn't mitigate this.
Also, the need to replace major reactor components many times over the life of the reactor, due to cumulative neutron damage, will itself cause very large operating costs.
You could imagine building a globe-spanning power distribution network. Solar panels on one side of the planet could provide power at night on the other side of the planet.
If we could transmit power across vast distances like that then we wouldn't even need to bother with solar. We could build a thousand nuclear power plants in the middle of nowhere. Unfortunately, power transmission suffers from line losses. Even a few hundred miles requires several hundred thousand volts to avoid losses. Maybe that's an easier problem to solve than fusion.
Use the local electricity to crack water into H2 and O2. Release the O2, use the local electricity to compress the H2 into liquid hydrogen, pump in across the country. The pipes themselves are a storage facility.
Looking at stories like this, you need to realize how far out of the running this technology is. The power density of ITER (gross fusion power of the reactor divided by the volume of the reactor, not just the volume of the plasma) is 50 kW/m^3. This is horribly low, about 1/400th the power density of a PWR reactor vessel. The power/$ is also horribly bad. The cost is going to have to come down by two orders of magnit…
You don’t speak for the people working on it, so your claim of sunk cost fallacy is null.
Sorry I'm a layman at best on the subject, buts whats the difference between this project and, for example, W7-X?
To get fusion there is a couple of ways: There is gravitational confinement (that is how stars do it, but it is impractically large for humans), there is inertial confinement (get enough energy out before it explodes, but that only works for hydrogen bombs and NIF, not for a reactor) and magnetic confinement (that is what we intend to use for reactors). Magnetic confinement works because a plasma consists of charged…
Not the guy that asked the question, but thank you for this - very informative :)