You could power America with renewables from a technical and economic standpoint. The biggest obstacles are social and political - what you need is the will to do it.
Mark Z. JacobsonA large-scale wind, water and solar energy system can reliably supply the worldโs needs, significantly benefiting climate, air quality, water quality, ecology and energy security ... [T]he obstacles are primarily political, not technical.
Mark Z. JacobsonYou can power the entire U.S. vehicle fleet with 73,000 to 145,000 five-megawatt wind turbines. That would take between one and three square kilometers of footprint on the ground.
Mark Z. Jacobson