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

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

#91

Post by elil17 »

disco_nap wrote: post #78
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…

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 and less hot. However, this all depends on the type of soil in the ocean floor.

One thermal study estimated that, with typical operating temperatures and burying depths, the sea floor temperature (of the soil, not the water) would heat by 10 to 18 degrees Celsius. This is enough to potentially interfere with ocean life, according to the authors of the study. Because of limits in the operating temperature of cables, a project like this would make a larger zone like this, but the maximum temperature would stay the same.

It’s important to note that we already mess up aquatic life by discharging thermal energy into bodies of water. High temperature water discharge from power plants can make rivers more friendly towards invasive species and shift the balance of aquatic ecosystems. This project might be a net neutral for aquatic life by reducing high temperature discharge into rivers while creating hot spots in the ocean.

Thermal study: https://doi.org/10.1093/gji/ggw195

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

#92

Post by boibombeiro »

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…

Something related. Brazil exports more water in form of grains and meat ("virtual water") to China than the huge South–North Water Transfer Project.

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

#93

Post by popinman322 »

mschuster91 wrote: post #53
delecti wrote: post #25

Earlier quoted context omitted.

Honestly it's kinda brilliant. With a big enough global network of overbuilt solar capacity you would avoid the problems of the duck curve and weather limitations.

It's hard to build an actual network out of DC power, which is partially why AC power took over.

Looks like DC power is more efficient for long haul cables.

https://engineering.stackexchange.com/a/19759

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

#94

Post by CoastalCoder »

sudhirj wrote: post #69
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…

For one, the power cables seem to be thicker and better shielded than the fiber optic ones. That aside, I don’t think any economy will rely purely on imported power - backups in the form of natural gas plants or grid scale storage will likely need to form part of the mix - there’s already the chance of some cloudy or rainy days over the solar farms, so it’s unlikely there isn’t a contingency.

What you say makes sense to me. OTOH, I get the impression that some of our infrastructure has a financial incentive to eliminate any reserve capacity. E.g., that snowstorm in Texas last(?) winter.

So I'm curious if having any non-trivial amount of electricity supplied by a usually-reliable mechanism becomes a long-term risk.

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

#95

Post by beecafe »

shagie wrote: post #73
BenjiWiebe wrote: post #58

Earlier quoted context omitted.

inverse square law

That applies to omnidirectional broadcast of power rather than beams.

You can't make a perfectly straight beam due to imperfect optics (and diffraction/Huygens principle), so a beam will only reduce the loss by a constant factor, but the area of the beam still increases by n^2 as it propogates.

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

#96

Post by ozborn »

GDC7 wrote: post #71

They have just overlooked that China has a solar area which is comparable (or just a tad inferior to Chile's). Gobi Desert. It's far easier to harness solar there and then push it onto the coast than building a 15,000km submarine cable

Gobi dessert doesn't produce solar power when it is night in China, but solar power from Chile can supply China at night.

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

#97

Post by simion314 »

blocked_again wrote: post #35
simion314 wrote: post #31

Earlier quoted context omitted.

Like what? Without government doing infrastructure probably most people would not have a electricity,water and a decent road in front of their home. Or how would we imagine an alternate reality where the governments are weak, so the industrial billionaires would be the ones deciding what infrastructure to build, what science to research, what level of education is needed etc. I can only see just a few roads , with ta…

Imagine a power generation company run by Joe Biden with his white House staff vs Elon Musk with his Tesla staff. Which stock would you buy? I bet the Biden company will go bankrupt in a few years let alone go public.

You mean Elon companies that have received a ton of money from various governments? Without the government Elon would make cars for rich kids only.

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

#98

Post by rich_sasha »

GDC7 wrote: post #71

They have just overlooked that China has a solar area which is comparable (or just a tad inferior to Chile's). Gobi Desert. It's far easier to harness solar there and then push it onto the coast than building a 15,000km submarine cable

Gobi is famously dusty, is that a factor? Also a lot of Chile is at high altitudes (thing Atacama), are PVs more efficient there?

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

#99

Post by janmo »

GDC7 wrote: post #71

They have just overlooked that China has a solar area which is comparable (or just a tad inferior to Chile's). Gobi Desert. It's far easier to harness solar there and then push it onto the coast than building a 15,000km submarine cable

Most electricity is consumed in the early evening and during the winter. That's why such a cable would make sense because of the time difference and the inverted seasons.

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

#100

Post by janmo »

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.

It is not only about night time but also about inverted seasons. When it is summer in Chile it will be winter in China.
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