Deutsche Bank's Vishal Shah, Jerimiah Booream-Phelps and Susie Min are out with an even more bullish projection: they think that the U.S. could hit 50 gigawatts (although this would still only be 2% of the entire U.S. energy picture):

 They offer five reasons for their outlook:

1)  Solar is already cost competitive in 10 states

Deutsche Bank estimates the levelized cost of energy for solar to be $0.11 to $0.15 per kilowatt hour, compared with $0.11 to $0.37 kilowatt hour for retail electricity, for states including New Jersey, New York, Connecticut and Vermont (along with the usual suspects like California).