Gartman is known for his off the wall predictions. Not a credible source in my book.
It's a typo -- should read 50,000 MEGAWatt-Hours per Year..... given about 3.5 Hours of Mean Insolation per day * 365 days per Year * 40 MegaWatts capacity.
Sentiment: Strong Buy
Earnings and growth are extremely compelling here. Solar is not going away... in fact, it is federally mandated!