For many countries, pure renewables plus batteries only works with an international grid. In a different thread here, Germany was coming up quite a bit during the dunkelflaute, and the only way to go pure renewable is to import energy from, say, Morocco.
It does achieve potential independence from current adversaries, but only by introducing dependence on other nations instead.
Countries like the US have it a little better independence-wise, except we need (a) significant buildouts of batteries that don't rely on rare earths, because we can't mine them here for environmental reasons, and (b) massive buildouts of solar panels in regions across the country.
The upper midwest has something similar to Germany's dunkelflaute- it gets cold enough windmills may even be net negative to keep their turbines ice free, and we can go weeks under total cloud coverage.
Supporting all of that is possible, but requires overbuilding the grid to such an extent that the carbon cost of the cement and metals added to the grid would extend the payoff period quite a bit. It's definitely not a free lunch, though probably better to start now than hope for miracle cold fusion or something equally silly.
It does achieve potential independence from current adversaries, but only by introducing dependence on other nations instead.
Countries like the US have it a little better independence-wise, except we need (a) significant buildouts of batteries that don't rely on rare earths, because we can't mine them here for environmental reasons, and (b) massive buildouts of solar panels in regions across the country.
The upper midwest has something similar to Germany's dunkelflaute- it gets cold enough windmills may even be net negative to keep their turbines ice free, and we can go weeks under total cloud coverage.
Supporting all of that is possible, but requires overbuilding the grid to such an extent that the carbon cost of the cement and metals added to the grid would extend the payoff period quite a bit. It's definitely not a free lunch, though probably better to start now than hope for miracle cold fusion or something equally silly.