...AND CHEAPER...:

These two projects, plus the electric output of solar panels at four Kroger grocery stores, and some energy-conservation efforts are saving the Cincinnati-based grocery chain $ 160 million a year on electricity, said Denis George, its energy manager. That is a lot of money that isn't going into the pockets of utilities.

From big-box retailers to high-tech manufacturers, more companies across the country are producing their own power. Since 2006, the number of electricity-generation units at commercial and industrial sites has more than quadrupled to roughly 40,000 from about 10,000, according to federal statistics.

Experts say the trend is gaining momentum, spurred by falling prices for solar panels and natural gas, as well as a fear that power outages caused by major storms will become more common. [...]

The growing number of companies that are at least partly energy self-sufficient is sending a shudder through the utility industry, threatening its revenues and growth prospects, according to a report earlier this year by the Edison Electric Institute, a trade association for investor-owned electric companies.

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