Re: For those who wonder...
So much misunderstanding and limiting understanding
AC is great because its easy to change voltages using just an old lump of iron and some copper windings.
It's also great because its easy to generate - being what naturally comes out of a magnet rotating inside a bunch of coils - or vice versa.
It's also great because it shows that the dynamos are slowing down under load, thus slowing down all synchronous motors attached to the grid and lowering the load.
Its bad for very big grids. Or undersea cables. Because very big grids have enough propagation delay to make a lot of out of phase current circulate - as do undersea links , on account of the massive capacitance they exhibit between conductors and ground.
This leads to greater losses due to cable resistance.
The UK grid is stabilised to have a long term average of EXACTLY 50Hz, though it will fluctuate under load.
It is not connected directly to the European Grid. All links are DC with frequencies at either end being independently variable.
The move away from turbines & transformers towards electronic inverters is not altogether welcome. Spinning mass accounts for the best short-term storage on the grid there is. load fluctuations are dealt with my the rotational inertia.
Adding massive amounts of highly variable - and over short time scales, as windmills trip in and out and clouds cover solar panels - renewable energy places a BIG strain on grid management. Germany has already had to relax its frequency control standards to accommodate Energiewiende and many factories that depend on 50hz stability have been forced to essentially install what amounts to massive crystal controlled UPS'es. Increasing electricity consumption still further.
Meanwhile the rapid deployment of power stabilised switch mode PSUs has meant that lowering frequency and/or voltage does not lower power drawn, thus depriving grids of a simple and natural way to keep supply and demand balanced.
We are fortunate that we have always run a separate grid even before Brexit.
Like most of the EU, the European grid is too big to manage and suffers too much political interference to be efficient.