Solar panels are being installed at Hills Flat Lumber in Grass Valley. The 30 kilowatt system was purchased from Plan It Solar at a cost of about $250,000 and produces enough power to run four to six standard houses. The projected monthly energy savings will be about 8 percent. This is good "if you're in it for the long haul," said owner Jeff Pardini. "We'll do this now and maybe more later," he said. The system installation is being done by California Solar.