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Having a fully automated solar cell fab locally would be wonderful. We'd reduce the need for big ships burning sulphur-rich heavy bunker fuel oil. We'd be more

Having a fully automated solar cell fab locally would be wonderful. We'd reduce the need for big ships burning sulphur-rich heavy bunker fuel oil. We'd be more resistant to China cutting us off without warning, as they did for rare-earth metals. Even a lights-out factory sometimes needs workers, so that is at least a few jobs. If you want a coal-related motive, try the obvious: Pennsylvania is an important swing state. Mines are hiring again, for both miners and engineers.

kragen 9y ago
Shipping solar panels overseas is not a significant source of bunker-fuel emissions, and it probably never will be. Complete solar panel modules, without legs, weigh about 10kg per kilowatt: https://www.amazon.com/ECO-WORTHY-10pcs-Watts-Module-System/dp/B06XXDZV4F/ref=sr_1_2?ie=UTF8&qid=1516667435&sr=8-2&keywords=1kw+solar+panel https://www.amazon.com/ECO-WORTHY-10pcs-Watts-Module-System/.... So each TEU of solar panels contains about 2.2 megawatts of generating capacity at 22 tonnes net per TEU. If the world installs 150 gigawatts of new solar capacity in 2018, that's about 70000 TEUs. The Emma Maersk carries 11000 TEUs on every voyage, so the amount of solar panels that will be installed worldwide in 2018 is about 6 shiploads. What about the future, when photovoltaic becomes the dominant source of marketed energy? According to the IEO, current total world marketed energy consumption is 20 terawatts (20'000 gigawatts), which would amount to about 90 million TEUs, or 8000 shiploads. Call it 30000 shiploads to account for photovoltaic's low capacity factor, typically in the 20%–30% range (though we can expect that to become more efficient as development moves to more equatorial areas with less clouds). There are currently about 9000 container ships in operation, so current world marketed energy consumption is about three trips for the world's shipping fleet, in the form of photovoltaic panels. Total container shipping volume is already about 470 million TEUs per year: https://en.wikipedia.org/wiki/Container_ship#Container_ports https://en.wikipedia.org/wiki/Container_ship#Container_ports We can presumably expect panels to become smaller and lighter as time goes on, further decreasing the energy needed for shipping, and eventually the proliferation of solar panels will depress the price of energy so low that not even bunker fuel can compete with syngas, at which point the bunker fuel emissions problem will be over. (Edited to correct order-of-magnitude calculation error.)
dylan604 9y ago
I've wondered about the fuel for large cargo ships. From my understanding, freight train engines are basically gas powered generators to produce 480v output to power an electric engine. Not my area of expertise, but this is supposed to be much more fuel efficient than straight combustible engine power. If that is the case, why would this not work for cargo ships as well?
- thatcat 9y ago
  Converting energy from chemical to electric then mechanical is only beneficial if you need a high torque at low rpm, like to start moving a train. Otherwise its more efficent to directly convert from chemical to mechanical.
- kragen 9y ago
  Diesel-electric locomotives convert from mechanical energy to electricity and back, which is reasonably efficient, but not 100% efficient. I don't know what efficiencies they get, but at small scales it's easy to hit 88% round-trip efficiency. The advantage is that, like a Prius, you can run the internal-combustion engine always at its optimal efficiency point, whether the train is going full speed or at literally zero speed. Internal combustion engines run extremely poorly at zero speed. Ship screws, on the other hand, can be designed to run at nearly any speed at all, and nearly all the time the ship is moving at exactly the same speed. So the screws are just coupled directly to the crankshaft of a two-stroke diesel engine the size of a fucking church which remains powered on for years at a time, always running at whatever speed it damn well pleases.

kragen 9y ago

Shipping solar panels overseas is not a significant source of bunker-fuel emissions, and it probably never will be. Complete solar panel modules, without legs, weigh about 10kg per kilowatt: https://www.amazon.com/ECO-WORTHY-10pcs-Watts-Module-System/dp/B06XXDZV4F/ref=sr_1_2?ie=UTF8&qid=1516667435&sr=8-2&keywords=1kw+solar+panel https://www.amazon.com/ECO-WORTHY-10pcs-Watts-Module-System/.... So each TEU of solar panels contains about 2.2 megawatts of generating capacity at 22 tonnes net per TEU. If the world installs 150 gigawatts of new solar capacity in 2018, that's about 70000 TEUs. The Emma Maersk carries 11000 TEUs on every voyage, so the amount of solar panels that will be installed worldwide in 2018 is about 6 shiploads. What about the future, when photovoltaic becomes the dominant source of marketed energy? According to the IEO, current total world marketed energy consumption is 20 terawatts (20'000 gigawatts), which would amount to about 90 million TEUs, or 8000 shiploads. Call it 30000 shiploads to account for photovoltaic's low capacity factor, typically in the 20%–30% range (though we can expect that to become more efficient as development moves to more equatorial areas with less clouds). There are currently about 9000 container ships in operation, so current world marketed energy consumption is about three trips for the world's shipping fleet, in the form of photovoltaic panels. Total container shipping volume is already about 470 million TEUs per year: https://en.wikipedia.org/wiki/Container_ship#Container_ports https://en.wikipedia.org/wiki/Container_ship#Container_ports We can presumably expect panels to become smaller and lighter as time goes on, further decreasing the energy needed for shipping, and eventually the proliferation of solar panels will depress the price of energy so low that not even bunker fuel can compete with syngas, at which point the bunker fuel emissions problem will be over. (Edited to correct order-of-magnitude calculation error.)

dylan604 9y ago

I've wondered about the fuel for large cargo ships. From my understanding, freight train engines are basically gas powered generators to produce 480v output to power an electric engine. Not my area of expertise, but this is supposed to be much more fuel efficient than straight combustible engine power. If that is the case, why would this not work for cargo ships as well?

thatcat 9y ago
Converting energy from chemical to electric then mechanical is only beneficial if you need a high torque at low rpm, like to start moving a train. Otherwise its more efficent to directly convert from chemical to mechanical.
kragen 9y ago
Diesel-electric locomotives convert from mechanical energy to electricity and back, which is reasonably efficient, but not 100% efficient. I don't know what efficiencies they get, but at small scales it's easy to hit 88% round-trip efficiency. The advantage is that, like a Prius, you can run the internal-combustion engine always at its optimal efficiency point, whether the train is going full speed or at literally zero speed. Internal combustion engines run extremely poorly at zero speed. Ship screws, on the other hand, can be designed to run at nearly any speed at all, and nearly all the time the ship is moving at exactly the same speed. So the screws are just coupled directly to the crankshaft of a two-stroke diesel engine the size of a fucking church which remains powered on for years at a time, always running at whatever speed it damn well pleases.