Shares of First Solar (FSLR) are down more than 18% this year and SunPower ( SPWR ) nearly 15%. SolarCity (SCTY ) shares have faired better, falling just 5%. This month the company secured $400 million in financing from Bank of America ( BAC ) to fund residential projects. Elon Musk, best known as Tesla's ( TSLA ) CEO, is also chairman of SolarCity. Related: Jay Leno hopes Tesla's critics are wrong As oil becomes more affordable, Najarian thinks the solar industry may be facing fewer government subsides. "There is a direct correlation with crude, I believe, and that kind of energy.