LA Times: Landfills, with the tendency to belch noxious greenhouse gases, have long gotten a bad rap from environmentalists. But now several clean-power technology companies believe waste can be a source of environmentally friendly energy. FlexEnergy, an Irvine company, showed off a pilot generator Thursday that converts previously unusable methane gas seeping from a Riverside County landfill into 100 kilowatts of electricity. That could be used to help run the sprawling landfill …