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Article is missing a key topic: how safe, desirable, and scalable are the technically feasible non-fossil alternatives to nuclear power? It also makes the same

Article is missing a key topic: how safe, desirable, and scalable are the technically feasible non-fossil alternatives to nuclear power? It also makes the same mistake nearly everybody does: focussing on electricity generation, which is responsible for about a third of emissions, and falling. It's also about a third of our energy needs. For example: in shipping, ammonia as fuel seems to be a leading candidate to replace fossil bunker fuel engines. 10 MW - 100 MW nuclear reactors are, to me, more desirable because safer. The energy economics of making and burning ammonia are dire, too. Reactors as drop-in replacements for gas turbines or for gas furnaces would allow continued operation of district heating systems in cold countries. Building heat is about #4 or #5 on the top 10 emitters. The alternative to district heat, installing electric heat pumps on all the buildings, seems costly by comparison. And they need electricity anyway. Any technology that is not already in use at the $10 billion scale¹ can't scale quickly enough to help with climate change, without massive government intervention.² So no BECCS, no hydrogen for transport, etc. Any technology that can't scale to provide at least 5 TW continuous (150 EJ per year) is also a non-starter.³ So biomass is a distraction. 1. Or that is a straightforward, near-zero-research combination of two or three technologies that are already in use at the $100B scale. We have 30 years to get to global scale. 2. We are going to need massive government intervention in order to get iron smelting (over 1 Gt per year, both iron and carbon dioxide) off fossil carbon. The same goes for industrial chemical feedstocks, and other things. 3. Total primary energy supply in 2015 was about 17 TW. If we allow developing countries to continue developing, we're probably going to need double that by 2050.

trinovantes 5y ago
I suspect we don't have nuclear powered cargo ships because then we'd need armed escorts for them. Otherwise any nations that want nuclear tech would try to hijack those ships on the open seas.
- tuatoru 5y ago
  Mmm, perhaps. With the number of satellites around these days, everyone knows where ships are, all the time. There's a big difference in technologies between making power and making a militarily useful weapon. If you want to develop the capability to do the latter, it's probably better to start from uranium ore than from piracy. It'll take quite a few years either way, and ore refining is more scalable.
- PaulHoule 5y ago
  The nuclear reactors used in submarines use (very) high enriched uranium which would be useful for weapons. It's implausible that any kind of marine reactor would use HEU. I'm also not sure it's plausible that commercial marine reactors would be light water reactors. Chloride salt reactors eat nuclear waste from LWRs like it was candy and are a lot more compact. They start out with high-burnup plutonium that couldn't go anywhere near a nuclear weapon. https://corepower.energy/technology/ https://corepower.energy/technology/ A fear I have though is that even big ships go down to the bottom thanks to rare and mysterious phenomena like https://en.wikipedia.org/wiki/Rogue_wave https://en.wikipedia.org/wiki/Rogue_wave
  - dredmorbius 5y ago
    There are on the order of 200 hull-losses per decade on commercial cargo ships. Much of that being concentrated along sea lanes which travel relatively close to shorelines, meaning both fisheries and marine habitats. There are about 80,000 cargo vessels presently registered --- that's a large number of nuclear engineers to train. And we probably won't be satisfied with flags of convenience. Or hauling bombs (ammonia fertiliser) in nuclear generating plants.

trinovantes 5y ago

I suspect we don't have nuclear powered cargo ships because then we'd need armed escorts for them. Otherwise any nations that want nuclear tech would try to hijack those ships on the open seas.

tuatoru 5y ago
Mmm, perhaps. With the number of satellites around these days, everyone knows where ships are, all the time. There's a big difference in technologies between making power and making a militarily useful weapon. If you want to develop the capability to do the latter, it's probably better to start from uranium ore than from piracy. It'll take quite a few years either way, and ore refining is more scalable.
PaulHoule 5y ago
The nuclear reactors used in submarines use (very) high enriched uranium which would be useful for weapons. It's implausible that any kind of marine reactor would use HEU. I'm also not sure it's plausible that commercial marine reactors would be light water reactors. Chloride salt reactors eat nuclear waste from LWRs like it was candy and are a lot more compact. They start out with high-burnup plutonium that couldn't go anywhere near a nuclear weapon. https://corepower.energy/technology/ https://corepower.energy/technology/ A fear I have though is that even big ships go down to the bottom thanks to rare and mysterious phenomena like https://en.wikipedia.org/wiki/Rogue_wave https://en.wikipedia.org/wiki/Rogue_wave
- dredmorbius 5y ago
  There are on the order of 200 hull-losses per decade on commercial cargo ships. Much of that being concentrated along sea lanes which travel relatively close to shorelines, meaning both fisheries and marine habitats. There are about 80,000 cargo vessels presently registered --- that's a large number of nuclear engineers to train. And we probably won't be satisfied with flags of convenience. Or hauling bombs (ammonia fertiliser) in nuclear generating plants.