You can run a generator to charge batteries or provide additional capacity when needed.
It would be ideal to have full coverage with "renewables" (isn't oil and gas a renewable just on a longer timeline?) but don't let perfect be the enemy of good if you want to move off-grid.
I do lack familiarity with the European environment, but between geothermal, wind, hydro and natural gas backup, is it really feasible as it is in places where solar gives 0.01 USD kWh prices?
You can run a generator to charge batteries or provide additional capacity when needed.
It would be ideal to have full coverage with "renewables" (isn't oil and gas a renewable just on a longer timeline?) but don't let perfect be the enemy of good if you want to move off-grid.