Smart meters, already installed in 7.5 million homes, have been the subject of two scientific studies, a state bill and numerous community meetings. Still, consumers are wary: Are they unhealthy? Will they give PG&E access to too much information?

To demonstrate the benefits of smart meters, PG&E set up a customer education station on Wednesday from 10:30 a.m. to 1:30 p.m. in the payment center at 2225 Folsom Street, and will do so again today.

A PG&E customer service representative on standby to demonstrate how smart meters work.

But only a lone reporter visited the station in the first hour on Wednesday. At the Home Depot-like display, a smart meter’s screen blinked while performing a complicated kilowatt calculation of the power used by two 100-watt lightbulbs plus a space heater and a customer service representative’s laptop computer plugged into the panel. 1.16 kW, it said at one second. 1.46 kW, it said the next, and so on.

“If you were running your washing machine between 2 and 3 p.m. today, you can go online tomorrow and see how much energy you were consuming,” said PG&E spokesman Jeff Smith. He emphasized that the new meters can give customers a better idea of how much they will owe PG&E before they get their bills.

Customers could also use their smart meter to identify energy-sapping appliances in their homes and unplug or replace them to use less energy and reduce their bills.

The meter’s display shows, in big numbers, how many kilowatt hours (kWh) of energy the consumer has used since the meter was installed; a smaller, three-digit number shows how many kilowatts the home is using at the moment. The meter also wirelessly transmits the data directly to PG&E.

Those radio frequency transmissions have made smart meters controversial, and their unpopularity has led city and county governments in Marin, Santa Cruz and elsewhere to symbolically ban their installation.  (They do not actually have the authority to stop PG&E from installing the meters.)

Responding to pressure from the public, California Public Utilities Commission (CPUC) President Michael Peevey has given PG&E until the end of the month to propose an opt-out program for consumers.

Assembly member Jared Huffman, D-Marin, introduced AB 37 in December to force PG&E to offer an alternative to customers who do opt out. A hearing is scheduled for April 4.

But are they dangerous?

Smart meters emit less radio frequency than cell phones and do not pose any identifiable health risk, according to a study by the California Council on Science and Technology.

“You’d have to have a smart meter on your home or business for a thousand years to get as much exposure to radio frequency as you get from a cell phone in one month,” said Smith.

Smart meters only transmit information to PG&E for a total of 45 seconds per day, he said.

Consumers’ privacy concerns remain. The new meters report energy usage by day, while traditional meters report it by the month.

“The pattern of energy usage can show you what appliances were in use, and you can see when somebody is home,” said Lee Tien, the senior staff attorney at the Electronic Frontier Foundation (EFF). “I think that a lot of [data] analysis is going to happen.”

The EFF, concerned with what PG&E might do with smart meter data in the future, is attempting to get the CPUC to adopt stricter consumer privacy rules.

“The extent to which this kind of information could violate people’s privacy is pretty great,” said Tien. “The details of what is happening inside your home should be nobody’s business but your own.”

PG&E maintains that smart meter information is protected from interception by unauthorized third parties, and that the new meter’s data collection is not significantly different from the old meter’s — other than that it is faster in delivering information to customers. “We’ve worked with the leading cyber-security experts in the industry to make sure our customer’s information is safe,” said Smith.

But Tien is wary of the interest that corporations like Google and Verizon have shown in seeing consumers’ energy usage data.

“It’s like when you weigh yourself. Every homeowner is going to want to see how they’re doing, but should everyone else get to see how you’re doing?”