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Robo-Connery OP t1_j03lmw0 wrote

Reply to comment by Englishgrinn in National Ignition Facility (NIF) announces net positive energy fusion experiment by Robo-Connery

So efficiencies gains are always possible but probably not unlimited. There are also fundamental science problems for both fusion regimes that need to be solved (even though I will claim ICF has far more of those problems).

> A solution to our energy/climate crisis for good?

I have a bog standard answer to this question: Just because there is unlimited fuel doesn't make it cheap. Fusion reactors will be, for the foreseeable future, extremely expensive. This means the energy they produce will be very expensive.

However, they will get cheaper as we learn to make them better and as energy prices rise there will always be a tipping point where they make economic sense. More importantly though is your mention of climate. While there are obviously some co2 emissions associated with fusion (due to the plant needing built and operated and the fuel collected etc.) the amount is trivial so the environmental benefit of fusion is huge. Traditional Nuclear power also shares many of these benefits too but produces larger quantities of waste (though fusion still causes nuclear waste due to neutron activation of materials) and requires larger quantities of fuel.

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m-in t1_j06ohmr wrote

It’s also worth mentioning what does it mean to be “expensive”: it’s not about numbers in a database in a bank somewhere. It’s about how much energy it takes to make all the stuff that you need for a fusion power plant.

Let’s now imagine that we’ll get to a stage when the first commercial fusion plant can be built

The design, build, and commissioning process of that plant will take about as much energy as that plant will produce through its entire lifetime. It’ll be basically sunk cost for investors just to get the design and operating process shaken down and ready for the next build. And that’s optimistic.

High tech plants like that take hundreds of thousands of man-hours of work, if not millions. While that work is going on, you’re spending resources just to feed and keep the workforce happy - a gross oversimplification, but think of how many resources it takes to run the equivalent of a large residential subdivision. That’s just to keep those people alive and happy so they can do their 8 hours of work per workday. And those people live across the planet pretty much, since many different industries will be providing raw materials, machining, design, assembly, and a host of other services.

As the technology advances and more plants are built, it’ll become profitable to operate one. Not the first one. Not the second one either.

*Happy workforce is a relative term and I’m far from claiming working people everywhere are happy with their jobs. What we should strive for, though, is for big projects to contribute to workers’ well-being everywhere in some way.

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