The recent recovery in First Solar shares is due to its success in selling utility-scaled systems to companies such as Berkshire Hathaway's ( BRK.A) Mid-American Energy. The same can be said for SunPower ( SPWRA), now 66% owned by Total ( TOT) of France. They both make and market solar systems, and their shares are up 20% since Nov. 21. The tipping point, the point at which these systems become more like PCs, comes when they can deliver power for less than the price of the electric grid. When solar is the cheap power it sells itself. Hawaii, which has already passed grid parity, finds that utilities are now unwilling to connect systems to their grids, although a commercial installation there can now pay for itself in less than a year, writes John Farrell of the Institute for Local Self-Reliance. As parity becomes more common on the much larger U.S. grid, this resistance will only grow. But opportunities will also grow in storing the excess power for use by generators, electric cars, or hydrogen. Once parity happens -- and General Electric ( GE) told Clean Technica last year it expects this in 2016 -- then suppliers of renewable energy become great investments. Just not before. Until then you want to be the salesman. At the time of publication the author had a position in GE.Follow @DanaBlankenhornThis article was written by an independent contributor, separate from TheStreet's regular news coverage.