Finally some good news for publicly traded solar companies. Yingli Green Energy's shares bounced 14 percent today on news the company has successfully reduced its wafer thickness from 200 microns to 180 microns. The 10 percent reduction means the company will save on feedstock costs as it brings down polysilicon per watt while jacking up wafer output per ingot. In announcing its 2008 guidance, Yingli also noted it has secured roughly 70 percent of its polysilicon for 2008. The vertically integrated supplier also pegged its 2008 module shipment target at around 260 MW. Yingli's stock suffered along with other public solar companies in a big slump that started around Christmas. Today's breakout may signal a light at the end of the tunnel for some stunned solar investors. My guess is that Yingli benefited from its vertical integration, which allowed it shore up its supply chain while also investing in the engineering breakthrough. If this is the case, it means good news for a few companies in a similar position, like SunPower. While the well-stocked companies break away, the rest of the pack will be stuck at the bottom for some time to come.