Keith Johnson, writing recently in the Wall Street Journal, does a commendably even-handed job laying out “Six Myths About Renewable Energy.”  
Citing the rapid progress renewables have made in recent years, he concludes that “Many of the debating points we hear today are based on outdated facts and assumptions that don't hold up anymore.”
Of the six myths he covers, it is Myth #2 — “Renewables Can Replace All Fossil Fuels” — that is especially salient.  While it is possible to have high levels of renewables, he notes it would be “a long, tough slog.”  
This long slog is exactly what America’s Power Plan was designed to address.
Johnson cites difficulties in siting, finance, market design and transmission.  America’s Power Plan tapped 150 energy experts to address these issues specifically, plus three more that Johnson doesn’t mention.
America's Power Plan addresses the changes in the power sector being driven by game-changing new technologies, consumer demand for cleaner, more efficient energy, an aging and increasingly obsolete grid, and dramatic reductions in the cost of renewables.
“There's no technical reason renewable energy can't provide 80% of the power in the U.S. by midcentury. But there are a host of challenges that would have to be met first.” 
Technically Feasible
Johnson starts by referring to the landmark study led by the National Renewable Energy Lab,Renewable Electricity Futures, which he accurately describes as finding that “technically, by 2050 the U.S. could get 80% of its electricity from renewable energy and keep the lights on every hour, every day, in every corner of the country.”
The REF study is different from other studies, in that it was the first to grapple with the when-and-where aspects of renewables.