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Tokamak fusion plants 10 times the output of the biggest power plants today are likely to work, but no one would want such huge plants on the grid. When it need

Tokamak fusion plants 10 times the output of the biggest power plants today are likely to work, but no one would want such huge plants on the grid. When it needs to shut down for maintenance, that amount of power cannot be easily replaced. If it was used only for hydrocarbon synthesis, hydrogen generation, or seawater desalination, this could work, but not for electricity generation.

philwelch 8y ago
> Tokamak fusion plants 10 times the output of the biggest power plants today are likely to work, but no one would want such huge plants on the grid. When it needs to shut down for maintenance, that amount of power cannot be easily replaced. If it was used only for hydrocarbon synthesis, hydrogen generation, or seawater desalination, this could work, but not for electricity generation. The United States has, according to a quick Google, over 8,000 power plants. If you replaced them with 800 fusion plants, wouldn't you still have enough redundancy to take them offline for maintenance? Sure, having a smaller number of power plants increases line loss, but there has to be some economy of scale where tokamak fusion starts winning. Thinking even bigger, if you have a 100x or 1000x scale fusion plant and used it for hydrocarbon synthesis, as you suggest, couldn't you use that plant to supply several downstream power plants that burn hydrocarbons and still, potentially, end up net-ahead? I dunno--my impression is that the theoretical yield of fusion is so high that you can very, very quickly start reaping benefits even if you're doing so in extremely inefficient ways. Once you get above break-even, even if you're only a couple percentage points above break-even, if can build a huge enough reactor, it adds up really, really, really fast. Fast enough that some rich technocratic dictatorship could, say, build a bunch of tokamaks and effectively corner the world oil market without drilling for a single barrel of natural oil. You'd have to think that fusion starts doing things to the cost of energy that Moore's Law did to the cost of computing, to the point where people actually wrap user-facing applications in gratuitous web browsers.
- baking 8y ago
  You still have the cost of steam turbines and generators just like a coal/oil/gas power plant. The main cost savings is the fuel cost, which is a small but significant fraction of today's electric power cost. There are theoretical proposals for direct conversion of electricity using the charged particles of certain fusion reactions (usually using Helium-3 mined from the moon) in different reactor designs but those are even further out than the toroidal magnetic confinement reactors (tokamaks, spherical tokamaks, and stellarators.)
- njarboe 8y ago
  I know it is really hard to believe that if fusion power was possible we as a society would just not choose to develop it, but that is the case. This philosophy/issue is discussed by many people, in many contexts and can be summarized by Peter Thiel's quote, "We wanted flying cars, instead we got 140 characters"[1]. The world had been on a runaway upward trajectory of technological improvements that peaked with the atomic bomb, nuclear power, and the Apollo program and then basically stopped. In the 1970's a huge demographic block started coming into power, the baby boomers, and for many different reasons they questioned all of this ever increasing "improvements". Humans seemed not to have enough wisdom to wield wisely the new levels of power tech improvements were giving them. The Vietnam "war" against a country that never attacked the USA, DDT and other pesticides were killing all the bugs and destroying natural ecosystems, Russia and the US were building up an arsenal of nuclear weapons that numbered in the tens of thousands and could destroy humanity in 15 minutes, nuclear power was getting started and promised to give us electricity too cheap to meter to fuck up the planet even quicker, we kept tearing down and cutting apart beautiful cities with more and more interstate freeways, modern architecture with its anti-human scale and design, Agent Orange, etc. It was probably a good idea for humanity to take a breather on improving tech. The geeks were denied the power to keep implementing more powerful tech and nuclear powered rockets and airplane research were shut down. Denied working with real world, geeks turned to computers and no one cared. How could one do anything scary with pure calculations? Well, whole libraries full of books have been written on the subject. For power generation just look at how it is priced for residential costumers. In California the price per kWh goes up the more you use, unlike almost any product. Our philosophy on power generation in the "tech capital of the world" is that we should do less of it, not more. Cheap power is a negative thing. It takes a strong sense of purpose to invest large amounts of money into a project that your peer group is going to say is a bad thing. As the boomers fade from power, I see some hope of humanity too gain back some of its dreams for a better future using more powerful tools but with more balance on keeping things good for humans. Elon Musk is a good example for a third way, I hope. Big power plants are a problem. The US generating capacity is about 1,000 Gigawatts [2] so if fusion power plants are huge at 20 Gigawatts, that is only 50 plants. One per state. You can see how one of those going down is going to be a problem. The average plant size is only 0.06 Gigawatts if your 8000 power plant number is correct. (All calculations liable to correction as this is just a quick web comment.) [1]Thiel's view expanded on his founders fund website:https://foundersfund.com/the-future/# https://foundersfund.com/the-future/# [2]https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_6_01 https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...

philwelch 8y ago

> Tokamak fusion plants 10 times the output of the biggest power plants today are likely to work, but no one would want such huge plants on the grid. When it needs to shut down for maintenance, that amount of power cannot be easily replaced. If it was used only for hydrocarbon synthesis, hydrogen generation, or seawater desalination, this could work, but not for electricity generation. The United States has, according to a quick Google, over 8,000 power plants. If you replaced them with 800 fusion plants, wouldn't you still have enough redundancy to take them offline for maintenance? Sure, having a smaller number of power plants increases line loss, but there has to be some economy of scale where tokamak fusion starts winning. Thinking even bigger, if you have a 100x or 1000x scale fusion plant and used it for hydrocarbon synthesis, as you suggest, couldn't you use that plant to supply several downstream power plants that burn hydrocarbons and still, potentially, end up net-ahead? I dunno--my impression is that the theoretical yield of fusion is so high that you can very, very quickly start reaping benefits even if you're doing so in extremely inefficient ways. Once you get above break-even, even if you're only a couple percentage points above break-even, if can build a huge enough reactor, it adds up really, really, really fast. Fast enough that some rich technocratic dictatorship could, say, build a bunch of tokamaks and effectively corner the world oil market without drilling for a single barrel of natural oil. You'd have to think that fusion starts doing things to the cost of energy that Moore's Law did to the cost of computing, to the point where people actually wrap user-facing applications in gratuitous web browsers.

baking 8y ago
You still have the cost of steam turbines and generators just like a coal/oil/gas power plant. The main cost savings is the fuel cost, which is a small but significant fraction of today's electric power cost. There are theoretical proposals for direct conversion of electricity using the charged particles of certain fusion reactions (usually using Helium-3 mined from the moon) in different reactor designs but those are even further out than the toroidal magnetic confinement reactors (tokamaks, spherical tokamaks, and stellarators.)
njarboe 8y ago
I know it is really hard to believe that if fusion power was possible we as a society would just not choose to develop it, but that is the case. This philosophy/issue is discussed by many people, in many contexts and can be summarized by Peter Thiel's quote, "We wanted flying cars, instead we got 140 characters"[1]. The world had been on a runaway upward trajectory of technological improvements that peaked with the atomic bomb, nuclear power, and the Apollo program and then basically stopped. In the 1970's a huge demographic block started coming into power, the baby boomers, and for many different reasons they questioned all of this ever increasing "improvements". Humans seemed not to have enough wisdom to wield wisely the new levels of power tech improvements were giving them. The Vietnam "war" against a country that never attacked the USA, DDT and other pesticides were killing all the bugs and destroying natural ecosystems, Russia and the US were building up an arsenal of nuclear weapons that numbered in the tens of thousands and could destroy humanity in 15 minutes, nuclear power was getting started and promised to give us electricity too cheap to meter to fuck up the planet even quicker, we kept tearing down and cutting apart beautiful cities with more and more interstate freeways, modern architecture with its anti-human scale and design, Agent Orange, etc. It was probably a good idea for humanity to take a breather on improving tech. The geeks were denied the power to keep implementing more powerful tech and nuclear powered rockets and airplane research were shut down. Denied working with real world, geeks turned to computers and no one cared. How could one do anything scary with pure calculations? Well, whole libraries full of books have been written on the subject. For power generation just look at how it is priced for residential costumers. In California the price per kWh goes up the more you use, unlike almost any product. Our philosophy on power generation in the "tech capital of the world" is that we should do less of it, not more. Cheap power is a negative thing. It takes a strong sense of purpose to invest large amounts of money into a project that your peer group is going to say is a bad thing. As the boomers fade from power, I see some hope of humanity too gain back some of its dreams for a better future using more powerful tools but with more balance on keeping things good for humans. Elon Musk is a good example for a third way, I hope. Big power plants are a problem. The US generating capacity is about 1,000 Gigawatts [2] so if fusion power plants are huge at 20 Gigawatts, that is only 50 plants. One per state. You can see how one of those going down is going to be a problem. The average plant size is only 0.06 Gigawatts if your 8000 power plant number is correct. (All calculations liable to correction as this is just a quick web comment.) [1]Thiel's view expanded on his founders fund website:https://foundersfund.com/the-future/# https://foundersfund.com/the-future/# [2]https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_6_01 https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...