DC Microgrids provide a means for decent energy services to be provided by a modest budget of renewable energy alone.
PV panel and windmills are not environmentally free, their manufacturing has a significant carbon and toxic footprint. On top of this, the most difficult and costly part of renewable energy systems, both financially and environmentally, is energy storage. Industrial solar and wind must be backed up by a fossil fuel capacity equal to these intermittent renewables. It’s economical for the utilities to keep these “back-ups” running at near capacity, so (surprise!) that’s what they do. At peak solar production, a lot of the extra power gets burned off in giant heat coils, because it’s cheaper than shutting down and restarting the natural gas or coal plants.
There has been growing excitement about large scale lithium battery storage for renewable energy, but this is a pipe dream of the wealthy. The environmental implications of such scale of battery manufacturing and disposal is mind-boggling, not to mention prohibitively expensive.
With grid tie there is no incentive to conserve, or use electricity when the sun shines. It perpetuates the illusion that electricity is cheap, abundant and always available. In the meantime, future generations- and communities at the front lines of fossil fuel extraction- ultimately pay the bill.