11–20 of 152 posts
Doesnt China have it's own supply of deserts a bit closer to home?
Isn't cheaper turn the electricity into liquid hydrogen?! Hydrogen can be stored for months, delivered by car, tubes, ships, etc Do not have many losses across long distances
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 the point you're piping it, well you may as well just pipe the electricity direct.
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 loss numbers on those systems.
At 52.5% energy lost in transmission (47.5% retained), this is still considerably more efficient than making hydrogen via electrolysis, liquefying it for shipping, and then burning the hydrogen in the receiving country to generate electricity.
This particular plan is breathtakingly ambitious and would no doubt cost a fortune. It may appear more attainable when (if?) the similar but smaller Australia-Singapore Sun Cable project gets built:
Doesnt China have it's own supply of deserts a bit closer to home?
I was immediately thinking about early morning in Asia, still dark outside, everybody puts the kettle on. If these long distance cables really can transport energy efficiently it might solve some of the challenges with renewables!
In the UK they actually have to plan for grid demand to skyrocket during ad breaks in certain TV shows because half the country puts the kettle on at the same time! In one episode of EastEnders, demand grew by 2290MW, nearly twice as large as any single UK nuclear reactor.
https://www.mylondon.news/news/zone-1-news/iconic-eastenders...
What percentage of power is lost to line-loss at those distances? And if you are going to cover long distances you usually push up to 750kV or more: how long before there's an insulation breakdown somewhere along your 15,000km and you get some very energetic arcing and sparking underwater? Not to mention that it makes for an interesting asset to target (though only a few nations have the "tools" to attack power cable…
Edit: a Chinese project with a 1.5%/1,000KM loss http://en.people.cn/n3/2018/0622/c90000-9474097.html
What percentage of power is lost to line-loss at those distances? And if you are going to cover long distances you usually push up to 750kV or more: how long before there's an insulation breakdown somewhere along your 15,000km and you get some very energetic arcing and sparking underwater? Not to mention that it makes for an interesting asset to target (though only a few nations have the "tools" to attack power cable…
https://en.wikipedia.org/wiki/High-voltage_direct_current#Ad...
Seems more efficient to desalinate water using solar and export it to China
Seems more efficient to desalinate water using solar and export it to China