Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Chile wants to export solar energy to Asia via 15,000km submarine cable

pv-magazine.com

Post reply on HN
Print view View original

131–140 of 152 posts

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#131

Post by elihu »

CoastalCoder wrote: post #50

I'm curious about this from a security perspective. With oil, coal, and natural gas, a cut in the supply network doesn't necessarily have an immediate impact. Buffers exist in some parts of the distribution network: ships holds, rail cars, and storage tanks. With electricity, it doesn't seem like we have much infrastructure for buffering the supply. So cutting those cables might have an immediate and significant impa…

I think that any country using links like this ought to have emergency backup power systems. I think this is actually a reasonable use of coal and/or natural gas: keep the infrastructure maintained and have it ready to take over if there's an emergency, but otherwise it sits idle. In most cases you wouldn't even have to build new plants, you'd just keep the old ones around that were displaced by renewables. (Though over time you may need to build additional plants as electric usage grows.)

Ideally you'd have some sort of international agreement that any fossil fuels used would be subject to a high carbon tax, so there'd be less temptation to just declare an emergency for no reason. But that would require more international cooperation on climate than what we've seen so far.

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#132

Post by spywaregorilla »

Negitivefrags wrote: post #80
mataug wrote: post #75

Earlier quoted context omitted.

Is ~50% retained more efficient than producing the solar power in Asia itself? Wouldn't it be better to generate this power in the deserts of the middle east, and the wide open plains of Central Asia and transmit that over shorter distances despite producing less power per solar panel ?

The whole point is that you can generate the power at different times. The deserts of the middle east get sunlight at a different time then South America. If we had a worldwide spanning power grid we wouldn't need to have a grid storage solution at all.

That's pretty crazy, but a really cool idea.

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#133

Post by elihu »

streamofdigits wrote: post #24

Hopelessly naive, I know, but shouldn't there be a global grid to optimally distribute electricity from solar irradiation rather than laying idiotic lengths of cable for political reasons? You want to connect the Pacific rim for that grid to work but I can easily imagine some intermediate "links" that seem to make more sense

It would seem to be more useful to connect more than just Chile and China (greater diversity of buyers and sellers of electricity), but maybe if China plans to consume the entirety of the cable's capacity, maybe a single point-to-point link actually does make the most sense in this case.

On the other hand, it's possible the cable will be under-utilized for half the day: when it's night time in Chile, they could buy power back from China, but will China have enough surplus? And is there enough demand in Chile (or its neighbors) to buy that much power?

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#134

Post by ncmncm »

trhway wrote: post #63
philipkglass wrote: post #14

European Commission Joint Research Center Technical Reports: HVDC Submarine Power Cables in the World https://publications.jrc.ec.europa.eu/repository/bitstream/J... According to table 1, losses for 800 kilovolt HVDC systems can be as low as 3.5% per 1000 km. That comes to 52.5% loss over 15,000 km. Losses should go lower at 1100 kilovolts (the highest voltage HVDC systems running today) but I can't find detailed los…

> than making hydrogen via electrolysis i'd say synth gas would be more versatile option. Also they can like Iceland export the energy as aluminum or similar products taking a lot of energy to produce. (and a bit dreaming - i think Andes is the place to build a large rail gun style space launcher, and not just for one launch per week like, i mean large spaceport launching stuff non-stop and this is where beside launc…

Making synth gas or ammonia would give them a multitude of markets competing for the product, vs. just China at the end of a wire.

But Chile probably needs a lot of capital to build out the solar arrays. A guarantee like that might be necessary to get China to pony up.

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#135

Post by ncmncm »

BenjiWiebe wrote: post #86
dukeyukey wrote: post #12

Earlier quoted context omitted.

> Isn't cheaper turn the electricity into liquid hydrogen?! Creating hydrogen is about 80% efficient, so you do lose a fair bit in the process. > Hydrogen can be stored for months, delivered by car, tubes, ships, That's the thing about hydrogen, it's tricky to store for long periods of time. It leaks real easy. And liquid hydrogen isn't very dense, about 7% of that of water, so it's hard to ship it in bulk. And at th…

And if you do store it, it has a nasty tendency to weaken it's container.

That tendency is usually exaggerated. At LH2 temperature and atmospheric pressure, it is not a problem. You get such troubles storing H2 at high pressure and temperature.

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#136

Post by laurent92 »

elil17 wrote: post #91
disco_nap wrote: post #78

Earlier quoted context omitted.

Are the losses thermal? How significantly could this change the ocean temperature near the cable? 50% of 600 GW is enough to cause a 10C increase in the temperature of 10 million liters of seawater every second?

The short answer is that if 10,000,000 L/s of well mixed water passed over the wire, it’s temperature would increase by 0.75 degrees Celsius. The long answer is that this is not quite the right way to view the question. There will be a temperature gradient around the cable - a zone where water is heated. The question is, how hot is this zone and how large is it. The cable will be buried, which makes the zone larger a…

What about the magnetic field? I think distance is required between the two sides of the cable to prevent arc, which also means there will be a magnetic field.

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#138

Post by duskwuff »

laurent92 wrote: post #136
elil17 wrote: post #91

Earlier quoted context omitted.

The short answer is that if 10,000,000 L/s of well mixed water passed over the wire, it’s temperature would increase by 0.75 degrees Celsius. The long answer is that this is not quite the right way to view the question. There will be a temperature gradient around the cable - a zone where water is heated. The question is, how hot is this zone and how large is it. The cable will be buried, which makes the zone larger a…

What about the magnetic field? I think distance is required between the two sides of the cable to prevent arc, which also means there will be a magnetic field.

Negligible. The magnetic field is produced in the space between the conductors, and falls off very rapidly (inverse cube) as you move away from that.

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#139

Post by mapmap »

mataug wrote: post #82
Negitivefrags wrote: post #80

Earlier quoted context omitted.

The whole point is that you can generate the power at different times. The deserts of the middle east get sunlight at a different time then South America. If we had a worldwide spanning power grid we wouldn't need to have a grid storage solution at all.

That's a good point, I can see how this could be better than battery based storage for night time. But I wonder if wind power coupled with some limited battery storage, geo thermal, and newer generation nuclear peaker power plants can solve this problem instead of laying a mega cable under the ocean.

>nuclear peaker power plants

Is that even a thing? Why would one not run the nuclear plant 24/7 after it has been paid for and constructed?

Re: Chile wants to export solar energy to Asia via 15,000km submarine cable

#140

Post by elil17 »

laurent92 wrote: post #136
elil17 wrote: post #91

Earlier quoted context omitted.

The short answer is that if 10,000,000 L/s of well mixed water passed over the wire, it’s temperature would increase by 0.75 degrees Celsius. The long answer is that this is not quite the right way to view the question. There will be a temperature gradient around the cable - a zone where water is heated. The question is, how hot is this zone and how large is it. The cable will be buried, which makes the zone larger a…

What about the magnetic field? I think distance is required between the two sides of the cable to prevent arc, which also means there will be a magnetic field.

Heat becomes an issue before magnets do. Magnets follow an inverse power law but thermal conduction regimes produce linear temperature gradients. The spacing required for cooling is greater than the spacing required for EM insulation except for very low power flows.
Post reply on HN