- Unfortunately, they are averaging the entire US, which is made of several grids, so the bad days are not that bad in their analysis. To fix those bad days, you'd need hella more storage, hella more capacity. e.g. 3-4x the renewables capacity than the normal need.
- Such a system has a very low resiliency because it depends on national grid. If Covid has taught us anything, it is the need for resiliency in the face of rare events. In this case unfavorable weather, broken transmission, etc.
- Cost projection is rosy... The panels, batteries, and storage are already very close to the material cost. Need some pretty fundamental tech transitions to improve further.
- If there is no policy change, nukes and nat gas will not be competitive 99% of the time because solar/wind are nearly free electricity and bid extremely low power prices that nuke/gas can't compete with. So even though they will provide the backbone and dispatchibility needed for on-demand power, they do not currently have the financial incentive to do so. We need resiliency and dispatchibility payments.
Report is Berkeley and GridLab, mostly policy wonks
A much better report from MIT: https://www.sciencedirect.com/science/article/abs/pii/S25424... or http://energy.mit.edu/research/utility-future-study/
Both are harder to read and give worse news, so probably won't be part of the policy discussion...
The report itself: http://www.2035report.com/wp-content/uploads/2020/06/2035-Re...
And the data explorer: https://www.2035report.com/data-explorer/?hsCtaTracking=aefa...