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by jjk166 37 days ago
Transmission losses are orders of magnitude lower than transportation energy costs. You both get dramatically less loss per kilometer, and you have way fewer kilometers to travel. Transmission does get less efficient over longer distances; if you had a 20000km long transmission line it would be less efficient than shipping fossil fuels, but you simply don't need to do that.

You have conversion losses to generate motion but these are again substantially less than the conversion of chemical energy to motion that occurs inside a combustion engine. Powerplants+electric motors will have conversion efficiencies around 30%; internal combustion engines will have conversion efficiencies around 10%.

With the exception of some remote locations or emergency situations with backup generators, you are almost certainly not consuming a fuel that requires refining to generate electricity. If you're burning coal or gas, it's coming from much closer, and it's being transported in bulk to the powerplant. Trucks taking fuels to the local distribution centers and ultimately gas stations are by far the largest transportation energy expense for petrol.

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The other nice thing is that the batteries on cars can effectively act as grid energy storage even without v2g. Simple offpeak/low rate charging setups can take the most efficiently generated cheap power.

In Australia power prices are often negative in the day due to solar and there's various variable rate plans you can get to take advantage (Australia dwarfs all other nations in per capita solar; even China is nowhere close per capita). I know workplaces that will actively encourage you to charge your car at work.

Power prices due to the excess solar keep falling - eg. 10% fall nationwide in July (middle of winter in Aus so not even near peak solar). https://www.theguardian.com/australia-news/2026/may/26/power...

For all the talk of 'solar can't replace fossil fuels' or 'electricity isn't green' Australia's gone and created a nation wide energy market that encourages rooftop solar and it's found itself with excess daytime energy at a time when the world has an energy crisis in Iran and the datacenters going up everywhere.

I don't disagree with you but every country is different. Australia gets a lot of sunshine and is sparsely populated, so plenty of room for solar anyway. This is not the case everywhere though.

It can be a good example though of how you overproduce during the day and use that to charge car batteries for example

Australia is at about 3,5 persons per square kilometre and as you say one of the most sparsely populated countries on earth.

Compare to for example Denmark at 149 persons per square kilometre. Denmark needs about 35 TWh per year in electricity, so about 1,7% of their land area would need to to covered with panels to supply that.

(This is obviously napkin math and just a thought exercise)

If they were to convert their sheep pastures to dual-use like this (https://www.americangrassfed.org/solar-grazing-with-sheep-a-...) Denmark would be almost 40% solar powered without giving up any additional land area.

Denmark obviously has a lot of wind power and should not convert to a majority solar power for their grid, but I want to illustrate that the land area use may not necessarily be such a strong argument against significantly increasing solar power in more densely populated countries.

So why is Denmark along with the Swiss currently working on Thorum?
A private company based in Denmark is seeing a business opportunity on the open electricity market when neighbouring countries are deliberately slow.

Because Sweden and Germany and Netherlands all have very high electricity prices due to stalled investments in new energy generation. For example the right-wing government in Sweden. has denied the building of over 340 coastal wind turbines of average 11kW a piece and 40 inland at average 6kW over the past three years because Sweden instead wants to build nuclear reactors. The motivation stated is that this wind power is not needed when nuclear will be built. Meanwhile a location for these new reactors has yet to be chosen.