A new report finds that the market for light-emitting diodes (LEDs) is set to grow substantially in the next 10 years, surpassing even compact fluorescent lightbulbs as an energy-efficient lighting option. By 2020, LEDs will cover 46 percent of the $4.4 billion U.S. market for lamps in the commercial, industrial and outdoor stationary sectors, driven by the overall push toward energy efficiency, according to a study released recently by Pike Research, a Boulder, Colo. cleantech market-research firm.