The price of solar modules has been falling all year, putting pressure on solar manufacturers. But falling polysilicon prices have put even more pressure on some of the most leveraged companies in the industry.

According to Bloomberg, the price of polysilicon has fallen 8.8% in the past week to $40.51 per kilogram. The pressure put on suppliers such as MEMC Electronic Materials (NYSE: WFR), LDK Solar (NYSE: LDK), and JA Solar (Nasdaq: JASO) in the second quarter is likely to become worse in the third and fourth quarter.

It also means suppliers such as GT Advanced Technologies (Nasdaq: GTAT) will be receiving fewer orders long-term as the industry sorts out this oversupply.

Good for some
The falling cost of polysilicon isn't bad news for all companies. Not all companies make all of their own polysilicon, and falling costs for third-party polysilicon can mean lower costs and higher margins for some manufacturers.

Many of the largest module producers make little to none of their own polysilicon, something that could create expanded margins in the future. Last quarter, SunPower (Nasdaq: SPWRA) paid $32.5 million to terminate a third-party cell-supply contract, something that may pay off in the end. Two of the largest manufacturers, Suntech Power (NYSE: STP) and Trina Solar (NYSE: TSL), buy a large percentage of their wafer capacity.

Foolish bottom line
Falling module prices mean cells, wafers, and polysilicon will all be put under pressure in the coming quarters. It looks as if companies that focus on polysilicon will take the brunt of it first, but this could provide opportunities for companies focused on module and cell production. Polysilicon is one of the main costs in a solar panel, and if prices remain low, as they are today, these companies would be the biggest winners.

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