Proving once again how beholden solar companies are to bottlenecking silicon supply, Suntech Power took a big hit following its earnings call on Wednesday. The company announced an EPS of $1.02 for 2007, below the $1.09 analyst consensus, with 4Q EPS at $0.29 versus a consensus of $0.36. Following the call, Suntech shares closed out the day down 12.3 percent to $40.24. A limited number of silicon supply contracts has forced Suntech to revise down its 2008 output plan to 530 MW, a far fall from previous estimates between 600 MW and 700 MW. The company has largely failed to lock in silicon supply contracts, which is a problem with silicon prices surging up to 30 percent higher on the spot market. Suntech's history of blowing past estimates has many investors disappointed in the company's performance. This must have SunPower's Tom Werner laughing all the way to the bank. Werner told the Piper Jaffray renewable energy investors conference on Wednesday he expects prices on long term supply contracts to drop between 30 and 50 percent by 2010 or 2011. Werner also told the crowd SunPower has 100 percent of its poly needs under contract. Clearly the Sun's Tech is no match for its Power.