The true comparison require a lot of data and work. One would have to first calculate how much subsidies that each government spend on energy production, how much tax money is spent on grid stability, how much the taxes are, how high the fee is for grid connection, and how much easy producer take.

Spot market prices is just whatever the price is in EU, since all the grids are connected and every country in EU must trade if they have surplus energy. It represent the collective supply and demand within EU.

Interesting. In many states in the US, cost per Kw/H is lower for businesses, even very small ones, than for residences.