Third-party natural gas providers siphon off some of PG&E’s business.

It’s not just Jehovah’s Witnesses and vendors of oranges going door-to-door around here. You may have also gotten a knock from someone asking to see your Pacific Gas & Electric bill.

They’re representatives from third-party natural gas providers called core transport agents (CTAs). Twenty-two CTAs are eligible to sell gas directly to PG&E residential and business customers. Some of them are canvassing neighborhoods in PG&E territory.

Despite electricity deregulation in California, PG&E still operates much like a monopoly: Its customers can’t choose a different energy distributor. But CTAs represent competition for the natural-gas slice of the PG&E pie.

PG&E’s own gas is priced at a variable rate, meaning it can change by the month. But some CTAs, including IGS Energy, offer customers a fixed rate, with no cancellation fee. “Consumers are able to lock in a gas rate for three years at this year’s pricing, eliminating gas price volatility,” IGS spokeswoman Kerri Ward writes by email. “We are able to benefit customers who want the peace of mind knowing that if rates go up, theirs won’t.”

Mindy Spatt, spokeswoman for San Francisco-based consumer advocacy nonprofit The Utility Reform Network (TURN), says CTAs offer legitimate alternatives to PG&E gas. “It is a murky area right now,” she says. “The service isn’t the scam. The concern is, the sales pitch could be a scam.”

She says customers should be wary of scare tactics, like salespeople saying the 2010 explosion of a PG&E pipeline in San Bruno is about to make natural gas prices spike.

“Let’s face it, customer trust of PG&E is at an all-time low,” Spatt says. “When they knock on your door and say, ‘Don’t you want to get rid of a company that blew up San Bruno?’ people may think, ‘Yeah.’”

PG&E spokeswoman Mónica Tell says the company is neutral. “We’re committed to educating our customers about their energy options,” she writes by email. “It is entirely the customers’ choice.”

Since PG&E gas prices fluctuate, it’s impossible to predict whether a CTA will save you money. In November, PG&E charged $1.11 per therm (a unit of heat equal to burning about 100 cubic feet of natural gas) for customers in Tier 1, meaning they use the lowest amount of gas. IGS charges a fixed rate of $0.70 per therm, plus a “customer charge” of $2.95 per month. PG&E gas delivery charges are added either way.

Spatt says she wouldn’t sign up for a CTA herself. “I’ll put my money on the lower rates TURN is advocating for,” she says. “If you haven’t noticed fluctuations in your gas bill in the past, you probably won’t in the future.” Debra ans