[tomthe]

If I (and only I) owned such a cable from Europe to the US, how much money could I make by buying cheap solar energy from the bright side and selling it to the dark side of the Atlantic?

First thought: 10 GW * $0.03/kWh 4 hours/day = $1.2Mio per day [0]

I am not sure about my assumptions...

[0]: https://www.wolframalpha.com/input?i=10+GW+*+%24+0.03%2FkWh+...

[londons_explore]

I suspect you might earn a lot more than $0.03/kWh on average.

The difference between typical market daytime and evening wholesale electricity prices is around $0.06/kWh in the UK right now: https://bmrs.elexon.co.uk/system-prices

[ben_w]

Probably more like 8 hours: you can sell in both directions, to US before sunrise in US, to EU after sunset in EU.

How much you can charge probably also depends on storage, but it seems plausible (same magnitude as current transmission/distribution costs?) to my amateur understanding.

[drtgh]

You are ignoring many variables, ranging from cable resistance losses and maintenance costs to signal re-synchronisation systems. Not to mention environmental factors such as seabed warming and subsequent changes in ocean currents, over time.

[tomthe]

Yes, of course I do ignore a lot in that calculation. I just wanted to calculate the biggest possible usefulness of this cable. Especially the resistance losses could be quite disastrous.

[eru]

Exploiting the pricing difference would probably diminish it?

[tomthe]

To some degree, yes. I just looked it up and the EU produced ~2500GWh in 2023, which is around 280 GW on average.