Starts with where the "there" is? The project in the sahara to power all of europe were even 1 cable cost millions and they plan a third. All the transformators. And batteries. Nothing holds forever.
But the bigger problem is for example that we just don´t have the rescourses on earth for even just replace all cars with electic cars. Even if I take that germany´s cars alone would use up all lithium in the world with truck loads of salt. We still have not talked about all of europe, russia, china, japan and america.
And what do solar panels and car batteries in common. Well they need lithium.
Copper is also becomming increasingly a problem (if we want to save the climate or not) just for the infrastruktur of our energy consumption.
And once the batteries are no longer usable we don´t know what we do with them just like nucular waste we just sit on them.
For having your cake and eat it we just don´t have the resources. We would need to cut down on energy hard, transport hard.