Fusion in the 1970s

[Vadrigos]

I'm creating a weird history setting with an organization I'm calling the US Department of the Threshold, and I need some insight into possible alternate historical outcomes, as one of the things that will result from their activities is the abrupt and speedy development of cheap, commercial fusion energy for municipal use (but not specifically transportation, as I want to make a world that's similar to ours but also different) in the 1970s. Ideas to slow the rollout while also any explosive consequences that might occur from its development would be welcome. i know OPEC wouldn't be happy, and i had the funny idea of averting the Iranian revolution too as the US might be more suspicious of BP should they come whining about lost oil profits when oil usage is in decline…

Essentially, this idea should be viewed as 'What if it really did take only 30-40 years to develop fusion like Fermi predicted?"

Anyways, anyone got anything?

 

[Cloak&Dagger]

By cheap do you mean cheaper than fission? Fusion is by its nature more difficult than fission, so if we're considering a realistic fusion reactor it probably wouldn't be cheaper than a cheap fission reactor.

 

[Sandy River DL]

By cheap do you mean cheaper than fission? Fusion is by its nature more difficult than fission, so if we're considering a realistic fusion reactor it probably wouldn't be cheaper than a cheap fission reactor.

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Depends on what you mean by 'cheap fission reactor'. No realistic fusion core would be cheaper than something like the Chicago Pile, and current tokamak designs are looking like they'd cost as much as an entire plant's worth of equivalent fission systems. On the other hand, fusion reactors don't need to be nearly as rugged as their failure mode is 'hydrogen fire' rather than 'radioactive deflagration'. Additionally, one of the biggest hurdles to practical fusion power has been getting the energy out, as historic designs have been thermal systems like fission and fossil-fuel plants, so the divergence probably includes some form of direct generation methodology like magnetic flux generation, which would also push costs down overall.

 

[Cloak&Dagger]

Depends on what you mean by 'cheap fission reactor'. No realistic fusion core would be cheaper than something like the Chicago Pile, and current tokamak designs are looking like they'd cost as much as an entire plant's worth of equivalent fission systems. On the other hand, fusion reactors don't need to be nearly as rugged as their failure mode is 'hydrogen fire' rather than 'radioactive deflagration'. Additionally, one of the biggest hurdles to practical fusion power has been getting the energy out, as historic designs have been thermal systems like fission and fossil-fuel plants, so the divergence probably includes some form of direct generation methodology like magnetic flux generation, which would also push costs down overall.

Click to shrink...

I mean cheap fission as in not strangled to death by red tape. I suppose it's possible fusion would end up cheaper by fission remaining red taped to death, but for things like warships that's not an issue so fission would probably remain standard.

 

[Sandy River DL]

I mean cheap fission as in not strangled to death by red tape. I suppose it's possible fusion would end up cheaper by fission remaining red taped to death, but for things like warships that's not an issue so fission would probably remain standard.

Click to shrink...

So cheap fission as in 'barebones, uncontained safety hazards' then. Because you've repeatedly made it clear you think basic safety requirements are 'useless red tape' in other threads. Conincidentally, the USN is one of the biggest investors in fusion research and the leading experts in what constitutes a safe fission reactor. Standards that, oddly enough, you don't like...

 

[Vadrigos]

So clearly clarification is required:

By cheap fusion, I mean a cluster of four or more toukamak fusion reactors (plasma torus design for the uninitiated) that, thanks to some anomalous scientific goosing towards certain narrow avenues of research by the Deparment, is able to compete with the productive capacity of 3-mile island's power plant operating at peak capacity, with the added benefit of increased safety should the worst happen.

The general idea is that none of this is specifically anomalous technology; merely the speed at which the vital data and theory was developed is. Primary ignition is achieved around 1956, with positive energy output following in 1965. Commercial viability is confirmed in 1970, and the first plant is opened in Albuquerque in 1972.

 

[Cloak&Dagger]

So cheap fission as in 'barebones, uncontained safety hazards' then. Because you've repeatedly made it clear you think basic safety requirements are 'useless red tape' in other threads. Conincidentally, the USN is one of the biggest investors in fusion research and the leading experts in what constitutes a safe fission reactor. Standards that, oddly enough, you don't like...

Click to shrink...

No, USN naval reactors are a good example of how efficient fission can be. They're pretty good cost to power.

So clearly clarification is required:

By cheap fusion, I mean a cluster of four or more toukamak fusion reactors (plasma torus design for the uninitiated) that, thanks to some anomalous scientific goosing towards certain narrow avenues of research by the Deparment, is able to compete with the productive capacity of 3-mile island's power plant operating at peak capacity, with the added benefit of increased safety should the worst happen.

The general idea is that none of this is specifically anomalous technology; merely the speed at which the vital data and theory was developed is. Primary ignition is achieved around 1956, with positive energy output following in 1965. Commercial viability is confirmed in 1970, and the first plant is opened in Albuquerque in 1972.

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But do they cost the same as 3 mile island, or have higher/lower build/operating costs?

 

[Memphet'ran]

I think oil would still be a valued resource in this scenario, with the politics that implies. Oil is primarily valuable as a vehicle fuel. Since the OP specified the fusion reactors are too big to stick in things like cars and trucks, unless this alternate history also sees precocious development of battery technology or something like that, oil would still have that niche.

After that, a lot depends on how much the historical trajectory of fusion power diverges from the OTL historical trajectory of nuclear power. Plausible options range from "fusionization of most national energy grids in the time span 1970-2000, very significantly different and better world" to "fusion gets nerfed by the same political and economic factors that nerfed nuclear OTL, we basically get OTL but with an additional layer of 'scientists remind public that clean energy is ready to go whenever.'" I think fusion would have less of a waste and potential contamination problem, since the reaction product is helium instead of radioactive heavy metals? I expect fusion to become a target of the anti-nuclear movement anyway though; I suspect a lot of this will come down to PR campaigns and the timing of events that influence them. On that note, I guess the 1970s is relatively lucky timing for a new "better" form of nuclear power to be rolled out, assuming the 1970s oil embargo still happens in this scenario; never mind that this new technology isn't directly applicable as an oil-replacement, the public will be relatively positively inclined toward a new energy source.

Assuming we get the relatively optimistic scenario, the biggest difference is likely going to be global warming being much less of a problem. With widespread fusionization starting in the 1970s I expect CO2 emissions to be way below their OTL levels by 2000. There will still be some, because there's likely to still be a lot of oil being burned as a vehicle fuels (about 1/3 of OTL emissions IIRC), but the problem will be much less bad and less urgent. Here's the first graph Google turned up for atmospheric CO2 increase over the twentieth century; this scenario would diverge from OTL around 1970, when CO2 looks to have been about 320 ppm; assuming gradual fusionization over the next few decades, I'd guess 2020s CO2 levels might be something in the region of 350 ppm; not far from 350.org's (in OTL very utopian) target.

 

[Cloak&Dagger]

I think oil would still be a valued resource in this scenario, with the politics that implies. Oil is primarily valuable as a vehicle fuel. Since the OP specified the fusion reactors are too big to stick in things like cars and trucks, unless this alternate history also sees precocious development of battery technology or something like that, oil would still have that niche.

After that, a lot depends on how much the historical trajectory of fusion power diverges from the OTL historical trajectory of nuclear power. Plausible options range from "fusionization of most national energy grids in the time span 1970-2000, very significantly different and better world" to "fusion gets nerfed by the same political and economic factors that nerfed nuclear OTL, we basically get OTL but with an additional layer of 'scientists remind public that clean energy is ready to go whenever.'" I think fusion would have less of a waste and potential contamination problem, since the reaction product is helium instead of radioactive heavy metals? I expect fusion to become a target of the anti-nuclear movement anyway though; I suspect a lot of this will come down to PR campaigns and the timing of events that influence them. On that note, I guess the 1970s is relatively lucky timing for a new "better" form of nuclear power to be rolled out, assuming the 1970s oil embargo still happens in this scenario; never mind that this new technology isn't directly applicable as an oil-replacement, the public will be relatively positively inclined toward a new energy source.

Assuming we get the relatively optimistic scenario, the biggest difference is likely going to be global warming being much less of a problem. With widespread fusionization starting in the 1970s I expect CO2 emissions to be way below their OTL levels by 2000. There will still be some, because there's likely to still be a lot of oil being burned as a vehicle fuels (about 1/3 of OTL emissions IIRC), but the problem will be much less bad and less urgent. Here's the first graph Google turned up for atmospheric CO2 increase over the twentieth century; this scenario would diverge from OTL around 1970, when CO2 looks to have been about 320 ppm; assuming gradual fusionization over the next few decades, I'd guess 2020s CO2 levels might be something in the region of 350 ppm; not far from 350.org's (in OTL very utopian) target.

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Fusion still produces waste by making the the reactor walls radioactive, but I'm not sure of the specifics of quantity on that.

 

[Sandy River DL]

No, USN naval reactors are a good example of how efficient fission can be. They're pretty good cost to power.

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The Ford-class CVNs' A1B reactor is around a billion per unit and run on weapons-grade HEU. Sure that's cheaper than commercial units, but it's not because they have fewer safety measures. It's the weapons-grade fuel I mentioned, combined with the fact that they, like other naval reactors, were designed to be produced on-mass unlike commercial units.

So clearly clarification is required:

By cheap fusion, I mean a cluster of four or more toukamak fusion reactors (plasma torus design for the uninitiated) that, thanks to some anomalous scientific goosing towards certain narrow avenues of research by the Deparment, is able to compete with the productive capacity of 3-mile island's power plant operating at peak capacity, with the added benefit of increased safety should the worst happen.

The general idea is that none of this is specifically anomalous technology; merely the speed at which the vital data and theory was developed is. Primary ignition is achieved around 1956, with positive energy output following in 1965. Commercial viability is confirmed in 1970, and the first plant is opened in Albuquerque in 1972.

Click to shrink...

Uh, tokamak won't get you commercial-scale fusion power. They need beryllium to turn thermal neutrons into heat, and beryllium isn't cheap. Like, the current world annual production is enough to build one reactor. They also get as radioactive as fission reactors, negating much of the advantages of fusion.

 

[Cloak&Dagger]

The Ford-class CVNs' A1B reactor is around a billion per unit and run on weapons-grade HEU. Sure that's cheaper than commercial units, but it's not because they have fewer safety measures. It's the weapons-grade fuel I mentioned, combined with the fact that they, like other naval reactors, were designed to be produced on-mass unlike commercial units.

Click to shrink...

Yeah, ~$2b per GW is competitive with land nuclear reactors. 3 Mile Island cost $2b for it's less than 1GW reactor.

Now obviously 1970s tech isn't as good, but 1970's is also about the time NPP prices started exploding, while the USN remained reliable the whole time.

A fusion plant that competes with 3 Mile Island will have a hard time breaking into warships.

 

[YuffieK]

They need beryllium to turn thermal neutrons into heat, and beryllium isn't cheap. Like, the current world annual production is enough to build one reactor. They also get as radioactive as fission reactors, negating much of the advantages of fusion.

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Most of that expense is because beryllium is VERY hard to extract as metal. You basically need to do it in a water and oxygen free environment. That said, it would probably fuel a space resource race for both it and helium-3 fuel.

 

[Sandy River DL]

Most of that expense is because beryllium is VERY hard to extract as metal. You basically need to do it in a water and oxygen free environment. That said, it would probably fuel a space resource race for both it and helium-3 fuel.

Click to shrink...

Amusingly enough, a ready source of He3 would remove the need for beryllium in fusion reactors, as D+He3 is an aneutronic reaction, excepting the occasional D+D reaction.

The other thing about beryllium is that it also has uranium impurities that are a bitch to remove, to the point that even the purest panels would see U235 fission and Pu239 production.

 

[Memphet'ran]

Uh, tokamak won't get you commercial-scale fusion power. They need beryllium to turn thermal neutrons into heat, and beryllium isn't cheap. Like, the current world annual production is enough to build one reactor. They also get as radioactive as fission reactors, negating much of the advantages of fusion.

Click to shrink...

Just looking at the results of a quick Google search, looks like graphite might be a viable cheap substitute for beryllium. That said, to extrapolate from what @YuffieK said, beryllium as a motivation for asteroid mining might be an idea for science fiction.

Amusingly enough, a ready source of He3 would remove the need for beryllium in fusion reactors, as D+He3 is an aneutronic reaction, excepting the occasional D+D reaction.

Click to shrink...

Helium 3 isn't easy to get (you'd need to either extract it from very low concentrations in Luna regolith or go to the giant planets to get it), so mining some beryllium-rich near-Earth asteroid(s) might be easier.

 

[Vadrigos]

Amusingly enough, a ready source of He3 would remove the need for beryllium in fusion reactors, as D+He3 is an aneutronic reaction, excepting the occasional D+D reaction.

The other thing about beryllium is that it also has uranium impurities that are a bitch to remove, to the point that even the purest panels would see U235 fission and Pu239 production.

Click to shrink...

I was already thinking of adding moon-mining to the setting, since we know helium 3 exists in certain quantities on the dark side. But all of these are informative. I was less focused on the technical aspects though; more on the sociopolitical. As such i've mostly got my answers now. Still, will likely have more questions down the line.

 

[Razzocnor]

Hmm, an interesting thought;
Commercial fusion might actually slow vehicle electrification. Why? Because pushing oil out from power generation means oil prices stay lower for longer, pulling the rug out from under electric cars, which are a lot more expensive to run in their immature stages. So you might see less of a push to move towards hybrid and electric vehicles, as oil based fuel stays cheap. Cheap clean electricity will still drive it eventually, but the process could get slowed down by years.

 

[Cloak&Dagger]

Hmm, an interesting thought;
Commercial fusion might actually slow vehicle electrification. Why? Because pushing oil out from power generation means oil prices stay lower for longer, pulling the rug out from under electric cars, which are a lot more expensive to run in their immature stages. So you might see less of a push to move towards hybrid and electric vehicles, as oil based fuel stays cheap. Cheap clean electricity will still drive it eventually, but the process could get slowed down by years.

Click to shrink...

Why would fusion lower oil prices? Oil largely isn't used for power, and where it is it's for the isolated type of power fusion won't replace.

With fusion making gas and coal obsolete, there will also be less oil discoveries and extraction.

 

[Delta Force]

By cheap do you mean cheaper than fission? Fusion is by its nature more difficult than fission, so if we're considering a realistic fusion reactor it probably wouldn't be cheaper than a cheap fission reactor.

Click to shrink...

Probably not since current nuclear reactor designs are remarkably similar to 1960s era steam plants that run on nuclear heat instead of fossil fuels. In fact, some nuclear power plants were even completed or converted into fossil fuel power plants.

Depends on what you mean by 'cheap fission reactor'. No realistic fusion core would be cheaper than something like the Chicago Pile, and current tokamak designs are looking like they'd cost as much as an entire plant's worth of equivalent fission systems. On the other hand, fusion reactors don't need to be nearly as rugged as their failure mode is 'hydrogen fire' rather than 'radioactive deflagration'. Additionally, one of the biggest hurdles to practical fusion power has been getting the energy out, as historic designs have been thermal systems like fission and fossil-fuel plants, so the divergence probably includes some form of direct generation methodology like magnetic flux generation, which would also push costs down overall.

Click to shrink...

Some early nuclear reactors essentially were just energy producing atomic piles.

The RBMK was considered to be the cheapest form of electricity generation ever devised and it is essentially a power producing atomic pile. It obviously isn't anywhere near the safest form of power though. Magnox is a similar design and also rather inexpensive although it doesn't have the same failure mode due to its use of carbon dioxide coolant instead of water.

The United States even had an energy producing atomic pile at Hanford, where the N Reactor was built with steam generators to provide power to the public power grid. The N Reactor was thermally stable though, unlike the RBMK, although it also lacked a containment structure.

So cheap fission as in 'barebones, uncontained safety hazards' then. Because you've repeatedly made it clear you think basic safety requirements are 'useless red tape' in other threads. Conincidentally, the USN is one of the biggest investors in fusion research and the leading experts in what constitutes a safe fission reactor. Standards that, oddly enough, you don't like...

Click to shrink...

There are a lot of expenses involved in nuclear energy that aren't actually related to safety. For example, the iconic cooling towers aren't actually required for a nuclear reactor to operate, they only exist to cool down the water before discharging it. Many nuclear reactors weren't designed with them and many weren't originally built with them. They are an environmental measure, not a safety one.

I mean cheap fission as in not strangled to death by red tape. I suppose it's possible fusion would end up cheaper by fission remaining red taped to death, but for things like warships that's not an issue so fission would probably remain standard.

Click to shrink...

There was a period in the 1960s in which nuclear energy was able to compete with coal purely on economic merits, and it is estimated that nuclear energy could regain a similar advantage over coal if fossil fuel facilities were required to have carbon capture and sequestration technology included. A water cooled nuclear reactor is remarkably similar to a coal fired power station except for the fact that its heat is produced by nuclear heat instead of chemical heat.

I think oil would still be a valued resource in this scenario, with the politics that implies. Oil is primarily valuable as a vehicle fuel. Since the OP specified the fusion reactors are too big to stick in things like cars and trucks, unless this alternate history also sees precocious development of battery technology or something like that, oil would still have that niche.

After that, a lot depends on how much the historical trajectory of fusion power diverges from the OTL historical trajectory of nuclear power. Plausible options range from "fusionization of most national energy grids in the time span 1970-2000, very significantly different and better world" to "fusion gets nerfed by the same political and economic factors that nerfed nuclear OTL, we basically get OTL but with an additional layer of 'scientists remind public that clean energy is ready to go whenever.'" I think fusion would have less of a waste and potential contamination problem, since the reaction product is helium instead of radioactive heavy metals? I expect fusion to become a target of the anti-nuclear movement anyway though; I suspect a lot of this will come down to PR campaigns and the timing of events that influence them. On that note, I guess the 1970s is relatively lucky timing for a new "better" form of nuclear power to be rolled out, assuming the 1970s oil embargo still happens in this scenario; never mind that this new technology isn't directly applicable as an oil-replacement, the public will be relatively positively inclined toward a new energy source.

Assuming we get the relatively optimistic scenario, the biggest difference is likely going to be global warming being much less of a problem. With widespread fusionization starting in the 1970s I expect CO2 emissions to be way below their OTL levels by 2000. There will still be some, because there's likely to still be a lot of oil being burned as a vehicle fuels (about 1/3 of OTL emissions IIRC), but the problem will be much less bad and less urgent. Here's the first graph Google turned up for atmospheric CO2 increase over the twentieth century; this scenario would diverge from OTL around 1970, when CO2 looks to have been about 320 ppm; assuming gradual fusionization over the next few decades, I'd guess 2020s CO2 levels might be something in the region of 350 ppm; not far from 350.org's (in OTL very utopian) target.

Click to shrink...

It's possible to create alternative fuels using a power station such as hydrogen or ammonia. A fusion reactor wouldn't be as efficient as a water cooled design though since many hydrogen production concepts take advantage of the reduced energy requirements involved in breaking high temperature water down into hydrogen and oxygen.

Why would fusion lower oil prices? Oil largely isn't used for power, and where it is it's for the isolated type of power fusion won't replace.

With fusion making gas and coal obsolete, there will also be less oil discoveries and extraction.

Click to shrink...

Petroleum power was a major source of energy during the 1970s. In fact, the growth of petroleum power in the era was actually far greater than nuclear power, peaking at almost 20% of electricity production at various points in that decade. In the year 1970 the United States was only getting 1% of its electricity from nuclear power.

Petroleum was cleaner than coal due to the ability to refine out sulfur and reduce acid rain in the period before flue gas desulfurization was adopted, although particulates are still much worse. Petroleum is also easier to transport than natural gas, important in a time before pipeline infrastructure was developed. It's easier to transport than coal too if you consider international trade. Coal export terminals require special infrastructure, a petroleum terminal is much easier to site. It wasn't until the early 1990s that petroleum ceased being a major electricity source in larger countries, although to this day many smaller islands still run on petroleum.

 

[Cloak&Dagger]

Petroleum power was a major source of energy during the 1970s. In fact, the growth of petroleum power in the era was actually far greater than nuclear power, peaking at almost 20% of electricity production at various points in that decade. In the year 1970 the United States was only getting 1% of its electricity from nuclear power.

Petroleum was cleaner than coal due to the ability to refine out sulfur and reduce acid rain in the period before flue gas desulfurization was adopted, although particulates are still much worse. Petroleum is also easier to transport than natural gas, important in a time before pipeline infrastructure was developed. It's easier to transport than coal too if you consider international trade. Coal export terminals require special infrastructure, a petroleum terminal is much easier to site. It wasn't until the early 1990s that petroleum ceased being a major electricity source in larger countries, although to this day many smaller islands still run on petroleum.

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Huh, I didn't know that.

 

[Vadrigos]

So after some further consideration, i've decided the fusion in this setting will be deuterium-based, since helium 3 mining isn't really viable until you have some sort of jovian energy fleet (cursed though that name may be). And while there probably will be a moonbase, it's going to be more like Prey's Pytheas Outpost or For All Mankind's thing than something from the movie Moon. However, to circumvent the radiation problem, I'm going to add a handwavy 'rad-leeching gel' substance loosely based on a real world substance being proposed to cleanup radiation particulates in the environment. This will then be stored in designated facilities in Nevada until some other recycling solution is found. Meanwhile, I may steal a few more things from Prey's timeline while I'm at it…

 

[CyberFemme]

So after some further consideration, i've decided the fusion in this setting will be deuterium-based, since helium 3 mining isn't really viable until you have some sort of jovian energy fleet (cursed though that name may be). And while there probably will be a moonbase, it's going to be more like Prey's Pytheas Outpost or For All Mankind's thing than something from the movie Moon. However, to circumvent the radiation problem, I'm going to add a handwavy 'rad-leeching gel' substance loosely based on a real world substance being proposed to cleanup radiation particulates in the environment. This will then be stored in designated facilities in Nevada until some other recycling solution is found. Meanwhile, I may steal a few more things from Prey's timeline while I'm at it…

Click to shrink...

Good. deuterium -trdtdum is by far the preferred method from what I've gathered from talking to people in the field.
You don't really need werd anti radiation gel tho. Literally either bury your waste or drop it into a deep part of the ocean.

Now, I actually don't expect fusion to do do much better than nuclear for displacing oil, because of regulatory capture and misinformation campaigns by oil companies.
A lot of anti nuclear sentiment is funded by big oil because they realize that nuclear is their main competition, and it will be the same with fusion. They'll talk about how fusion neutrons are more intense and generate more activated waste, they'll whip up NIMBYs, they'll buy senators and put regulatory blocks in place.

Also keep in mind that a fusion plant is going to be even more expensive than a fission one. So, the issues with high up front costs that fission plants have will be even more pronounced for fusion.

I guess at the end of the day the real question is what purpose is fusion supposed to fulfill in the story?

 

[Vadrigos]

Good. deuterium -trdtdum is by far the preferred method from what I've gathered from talking to people in the field.
You don't really need werd anti radiation gel tho. Literally either bury your waste or drop it into a deep part of the ocean.

Now, I actually don't expect fusion to do do much better than nuclear for displacing oil, because of regulatory capture and misinformation campaigns by oil companies.
A lot of anti nuclear sentiment is funded by big oil because they realize that nuclear is their main competition, and it will be the same with fusion. They'll talk about how fusion neutrons are more intense and generate more activated waste, they'll whip up NIMBYs, they'll buy senators and put regulatory blocks in place.

Also keep in mind that a fusion plant is going to be even more expensive than a fission one. So, the issues with high up front costs that fission plants have will be even more pronounced for fusion.

I guess at the end of the day the real question is what purpose is fusion supposed to fulfill in the story?

Click to shrink...

Bold of you to assume I won't have the Department of the Threshold just quietly beat the shit out of oil lobbyists in back alleys o keep them from pushing regulatory capture.

But seriously, will probably hand wave a little bit of this stuff too. Also, the gel will allow me to undercut a lot of those NIMBY concerns, AND reuse infrastructure.

 

[RoseEmbolism]

The main issue I see is that one really can't "just have fusion power" in the 70s, any more than we can just have machine learning. Fusion is a fiendishly difficult proposition, well beyond the technology of the time, so I think you'd have to have something SFional that acts like fusion, yet really isn't.

So here's a few possibilities:

• Runaway: Unlike normal fusion, this is a zero-point energy process that extracts energy from the Quantum Foam using a self-sustaining field effect. Using it to heat is how you get a working fluid to run a magnetohydrodynamic power plant. The problem is, if it runs wild, they're may be no stopping it.
• Product of a crashed UFO: Flying Saucers are very 70s. It's basically a weird literally black box technology that we really don't understand, though we can duplicate them. Actually, we don't-they duplicate themselves under the exactly right conditions. And if we make too many of them, the aliens will notice. Better set up a UFO defence agency hidden as a movie studio...
• Espers: what's more 70s than ESP? This fusion system requires telekinetics to, I dunno, convince the plasma to choose it something. But aside from the limited supply of espers, there's the fact that some of them might not want jobs as living power generators, or others may have more selfish, sinister uses for their abilities...
• Dimensional Weirdness: you get your energy by opening a crack in the space tone continuum. This can have all kinds of weirdness ranging from time and space distortion, time ghosts, people from alternate universes, dinosaurs...and the longer it goes on, the more "corrupted" the area gets (The Zone, The Southern Expanse, etc.)
• It's an evil plot: But they were, all of them, deceived, for another Fusion Reactor was made. In the land of California, in the fires of Stanford, the Dark Lord Teller forged in secret a master Fusion Reactor, to control all others. And into this Fusion Reactor he poured his cruelty, his malice and his will to dominate all life. One Fusion Reactor to rule them all...

 

[Mad Bad Rabbit]

Another materials issue for tokomaks: you will need several tons of niobium for the superconducting magnets. This will have a substantial impact on the economy and politics of 1970s Brazil (since they have far and away the biggest reserves).

The "nuke away" gel will have to deal with radioactive nickel from the titanium plasma-facing wall and all the stainless steel plumbing and structural members.

 

[Cloak&Dagger]

The main issue I see is that one really can't "just have fusion power" in the 70s, any more than we can just have machine learning. Fusion is a fiendishly difficult proposition, well beyond the technology of the time, so I think you'd have to have something SFional that acts like fusion, yet really isn't.

So here's a few possibilities:

• Runaway: Unlike normal fusion, this is a zero-point energy process that extracts energy from the Quantum Foam using a self-sustaining field effect. Using it to heat is how you get a working fluid to run a magnetohydrodynamic power plant. The problem is, if it runs wild, they're may be no stopping it.
• Product of a crashed UFO: Flying Saucers are very 70s. It's basically a weird literally black box technology that we really don't understand, though we can duplicate them. Actually, we don't-they duplicate themselves under the exactly right conditions. And if we make too many of them, the aliens will notice. Better set up a UFO defence agency hidden as a movie studio...
• Espers: what's more 70s than ESP? This fusion system requires telekinetics to, I dunno, convince the plasma to choose it something. But aside from the limited supply of espers, there's the fact that some of them might not want jobs as living power generators, or others may have more selfish, sinister uses for their abilities...
• Dimensional Weirdness: you get your energy by opening a crack in the space tone continuum. This can have all kinds of weirdness ranging from time and space distortion, time ghosts, people from alternate universes, dinosaurs...and the longer it goes on, the more "corrupted" the area gets (The Zone, The Southern Expanse, etc.)
• It's an evil plot: But they were, all of them, deceived, for another Fusion Reactor was made. In the land of California, in the fires of Stanford, the Dark Lord Teller forged in secret a master Fusion Reactor, to control all others. And into this Fusion Reactor he poured his cruelty, his malice and his will to dominate all life. One Fusion Reactor to rule them all...

Click to shrink...

I'm definitely skeptical of a fusion power plant in the 70's, but a thermonuclear power plant seems possible. It works in bombe, clearly.