A push by California's electricity provider to modernize its power grid is turning into a public relations disaster, as allegations mount that it's responsible for stratospheric overcharges.

At issue are the 10 million smart meters Pacific Gas & Electric, or PG&E, is rolling out to customers throughout the state. The digital meters, unlike the analog devices they're replacing, provide two-way communications between electricity users and the power stations that serve them. That eliminates the need for meter readers to visit each customer to know how much power has been consumed. ...

PG&E, and the providers of the smart meter gear take strong exception to those claims.

"The manufacturers test and certify the meters before they leave the factory," said PG&E spokesman Paul Moreno. "We also do some testing of meters upon arrival, and when meters are deployed in the field, before we convert the billing, we also check usage reads to ensure they're consistent with a customer's historic usage."

Once the complaints started rolling in, PG&E began paying visits to angry customers to test their meters. So far, it has tested more than 1,100 of them and none has been found faulty, he said.

Moreno said customers' bills are rising not as a result of the new meters, but because of recent rate increases and a hotter-than-normal summer, which has driven up air-conditioning costs.

Landis+Gyr and Silver Spring Networks, two of the companies providing technology for the smart meters, also insist their gear has been rigorously tested. Among other criteria, the equipment must pass accuracy and performance muster spelled out in in ANSI C12.20, they say.

"The system itself is working exactly as intended," said Eric Dresselhuys, an executive vice president for Silver Spring. "The accuracy of the meters and the accuracy of the system in total is excellent."

Erfan Ibrahim, a technical executive at the Electric Power Research Institute, also argues that the meters are accurate.

"If the accuracy was in question, all the meters would be showing errors because it would be a structural issue," he said. To date, the complaints amount to a tiny fraction of the people using them.