Comment by jl6
1 day ago
Let's hope someone can do the same for grid-scale seasonal storage. "Excess" solar electricity won't be free in (noon, summer) if you can easily bank it for (night, winter).
1 day ago
Let's hope someone can do the same for grid-scale seasonal storage. "Excess" solar electricity won't be free in (noon, summer) if you can easily bank it for (night, winter).
A second solution is to overbuild so you have enough even in winter. Easier to do near the equator.
A third solution is to pipe it across timezones using HVDC and accept some level of efficiency loss and some geopolitical risks.
A fourth solution is to mix lots of wind, which performs better in winter and cancels out the lower insolation.
Realistically it's going to be all of the above, with the balance determined by local factors.
Related to overbuilding, vertically mounted solar panels can help flatten the generation curve during the day, and may perform better than "optimally tilted" panels on winter, especially where snow might otherwise be a problem.
Power travels near the speed of light. In theory, the entire globe can be connected and countries with daylight can supply those at night in a cycle.
This isn't going to happen simply because it would introduce enormous strategic vulnerabilities. The first act ina war would be to sever an opponent's grid connections to their neighbors because that would massively erode their ability to maintain an orderly civil society.
This won't happen because the lines are bi-directional. It would be like chopping off their own energy supply. Because of the Earth's rotation, neighbors can take advantage of each other's sunlight. Parts of Europe and North Africa's energy markets are already working on this.
For the past 100+ years, the US has been spending a significant amount of money on protecting oil supplies to protect its oil billionaires and its economy. It's the #1 budget item, outspending the combined military spending of the next 10 economies. This can be reduced to zero, and ultimately, the $ 39 trillion deficit can be eliminated.
1 reply →
Or if everyone depends on another maybe we will not go into a war with each other.
3 replies →
We would need impractically high voltages to minimize power loss over long distances.
Maybe something like microwave transmission or cheap superconductors will solve it.
The loss is not that much - approximately 3.5% per 1000km. IIRC the Changji-Guquan HVDC line reported around 8% over 3300km thanks to working at 1100kV.
Extend that to 10k km and you're looking at approximately 25%, but if it's surplus solar, who cares?
Such a line costs as much as a highway broadly speaking, so it's not impossible to build.
4 replies →
Regional grids are connected via tie-lines, and I heard international grids are also starting to become more connected in this way too. Though, I'd imagine it's complicated to send power from one side of the planet to the other. For starters grids can have different frequencies that need to be converted between. Also all transmission lines are subject to loss factors. In addition all the intermediary transmission companies have to route the power and avoid congestion on their grids, Then you have deal with all the financial settlement of the wheeling charges, which if you have to go through multiple grids and multiple currencies sounds like fun to deal with.
My understanding of the intentions of connecting international grids is for things like emergency supply of electricity to a different grid to stabilise the frequency and prevent blackouts.
Do we have good enough conductors for that?
Utility conductors are just aluminum wrapped around a steel core, air is the insulator. You can theoretically handle voltage drop with larger conductors, and there are probably ways to ‘boost’ power over a long transmission line run. I deal with electrical wiring past the utility service entrance and am not super familiar with the utility side so perhaps an EE who works on the grid can chime in with more detail.
I also know breakers for HVDC are extremely challenging to make, AC power has the benefit of sine waves crossing the zero line so power can be switched/broken a lot easier than with DC.
It's a thread about Australia not Austria.