Coming in with a $6.92 billion market cap (the total dollar market value of the company's outstanding shares) is First Solar, the cadmium-telluride thin-film solar panel builder and project engineering, procurement and construction (EPC) company.

In the most recent quarter, First Solar set a new world record for CdTe cell efficiency at 21 percent, logged a full-fleet average efficiency of 14.0 percent and generated operating cash flow of $118 million. It's now at the top of the U.S. solar market cap hit parade.

Coming in second, and soon to be a silicon panel manufacturer, is fast-growing financier and installer SolarCity, which just logged a record quarter for bookings and deployment.

Market capitalization of U.S. solar firms:

First Solar CdTe module maker, EPC $6.92 billion
SolarCity Residential PV installer, financier $6.5 billion
SunPower c-Si module maker, EPC $5.98 billion
SunEdison c-Si module maker, EPC $5.6 billion
TerraForm Power SunEdison solar project YieldCo $3.25 billion
GT Advanced PV panel manufacturing equipment $2.23 billion


Strong solar stock prices are helping to accelerate the market. Notably, the top four companies on this list are vertically integrated, and five participate in the consistent yield of distributed generation projects. Recently buoyant stock prices have allowed these companies to be as acquisitive as needed and are helping increase solar adoption and reduce costs. (First Solar acquired TetraSun's c-Si technology; SolarCity has acquired Silevo's c-Si business, Zep, Paramount and Common Assets.)

Compare that to the market caps of the Asian module and poly makers traded on U.S. exchanges:

GCL-Poly Polysilicon $5.3 billion
Canadian Solar $1.37 billion
Trina Solar $812.5 million
JinkoSolar $802.9 million
Yingli Green $623.5 million
JA Solar $396.3 million
ReneSola $270.5 million
Hanwha SolarOne $182.1 million
China Sunergy $45.4 million


Or the market caps of the inverter builders:

SunGrow $1.84 billion
Advanced Energy $732.8 million
SMA                  $718.3 million
Enphase Energy $481.8 million


SunPower is essentially capacity-constrained and looking to add hundreds of megawatts of panel production. Other panel vendors are adding capacity for this next market phase. But clearly, the stock market favors the downstream or integrated solar approach rather than pure-play hardware manufacturers.    

That $3 billion to $7 billion range that included a cluster of solar firms is in the range of E*Trade ($6.1 billion), Pepco Holdings ($6.7 billion), a utility in the mid-Atlantic that serves more than 2 million customers, or Hawaii's utility holding company HEI ($3.48 billion).

Apple is the market cap leader at $574.6 billion.

These heady valuations could set the bar for solar IPO aspirants such as Vivint Solar (S-1 filed) or Sunrun (rumored to be considering an IPO).


Market caps current as of August 12, 2014.