Charles Boucher, a former semi analyst who now runs Boucher-Lensch, a boutique investment bank based in Sunnyvale, Calif., advises sticking with vertically integrated companies, with less exposure to any single element of the industry's cost structure. (Like poly, say.) Ergo, he likes SunPower (SPWR), which in addition to making the industry's highest-efficiency cells, owns an integration and installation arm called PowerLight. SunPower, highlighted in our solar story of 2005, is up about 180% since its initial public offering later that year.

Boucher also likes some Chinese solar companies, including Canadian Solar (CSIQ), Suntech (STP) and Yingli Green Energy (YGE). For a bet on the U.S. installation business, he notes, the pure play is Akeena Solar (AKNS), though it has the most to lose if Congress fails to extend the solar tax credit.

Boucher also likes some Chinese solar companies, including Canadian Solar (CSIQ), Suntech (STP) and Yingli Green Energy (YGE). For a bet on the U.S. installation business, he notes, the pure play is Akeena Solar (AKNS), though it has the most to lose if Congress fails to extend the solar tax credit.

Boucher also likes some Chinese solar companies, including Canadian Solar (CSIQ), Suntech (STP) and Yingli Green Energy (YGE). For a bet on the U.S. installation business, he notes, the pure play is Akeena Solar (AKNS), though it has the most to lose if Congress fails to extend the solar tax credit.

Boucher also likes some Chinese solar companies, including Canadian Solar (CSIQ), Suntech (STP) and Yingli Green Energy (YGE). For a bet on the U.S. installation business, he notes, the pure play is Akeena Solar (AKNS), though it has the most to lose if Congress fails to extend the solar tax credit.

Lehman analyst Vishal Shah has a contrarian take on MEMC; he thinks the shares are already discounting a big drop in poly pricing.

Shah also likes First Solar (FSLR), the solar play with by far the largest market cap. Among its charms: It has no poly exposure, because it uses a compound called cadmium telluride for its solar panels. Ries notes that First Solar has far lower costs per kilowatt hour than its silicon-based competitors; at current poly prices, he says, "it's not a fair fight." Not until polysilicon drops to $70 per kilogram, he says, do the comparative economics for First Solar "get strained."

JA Solar (JASO), which makes solar cells, could double capacity without accessing the capital markets, Shah says.