NEW YORK—The first LED bulbs that are about the same size and brightness as regular 100-watt bulbs are reaching stores. They provide an alternative to compact fluorescents after the federal government banned the production of regular 100-watt bulbs at the start of the year because they're energy-inefficient.

Using light-emitting diodes, the new bulbs from Osram Sylvania use 20 watts and cost $50. They are designed to fit regular light fixtures. However, the bulbs are slightly larger than regular bulbs, so they may not fit in all lamps.

Osram's bulb is in limited release at some Lowe's stores, but competitors aren't far behind. Philips plans to start selling its own, slightly brighter 100-watt equivalent on Home Depot's website starting in a few weeks for about $55.