Some news items this morning from American high-efficiency solar panel leader SunPower give a good indication of how much things have shifted for the solar industry over the past two years. First, the good news — San Jose, Calif.-based SunPower reports that it has built a solar module that can achieve greater than 20 percent efficiency in converting sunlight to electricity, using its solar cells with efficiencies of 22.4 percent. The more power you can get per square inch of panel, so to speak, the cheaper the rest of your “balance of system” costs will be. Two years ago, efficiency ratings were about all you heard anyone talk about in the solar manufacturing field — that, and costs per watt. But that brings us to the bad news for SunPower today, as the company reports that falling solar markets in Germany (the world’s biggest buyer of solar panels) and Italy (which has seen a government incentive-fueled boom sputter amidst program cutbacks) will likely drive down prices by 20 percent or so over the coming year. SunPower got about one-third of its business last year in Italy, so it has to compete with everyone else — particularly low-price Chinese panel manufacturers — on price elsewhere. Efficiency is critical — but so is keeping down costs.