How your gas bill works — and why customers are complaining about higher gas bills

Southern Californians are cranking up the heat this chilly winter — the coldest in several years — and getting a shock when a sky-high gas bill arrives.

Los Angeles City Councilman Mitch Englander wants the city to investigate. His constituents are complaining their gas bills are far higher than normal. They suspect it's to cover costs of the big natural gas leak near Porter Ranch, or new electronic gas meters that can be read from the street.

SoCal Gas spokesman Mike Mizrahi says bills are higher, but not because of new meters or the gas leaking from a broken well.

"It has not affected customers at all," Mizrahi said. "November and December were the coldest such months since 2011, so folks get surprised."

Some of that sticker shock has been showing up in comments on a Facebook group for Porter Ranch residents. Some have said their bill skyrocketed even though they had relocated away from their homes and were not using their furnaces while absent.

The part of a SoCal Gas bill that changes from month to month covers what SoCal Gas pays to buy gas from suppliers. This December it actually cost less than the previous year — just 32 cents a therm (a unit of measure for how much heat the gas would produce when burned) versus nearly 49 cents in December 2014.

Another part of the bill covers the cost to move gas through storage and the distribution system. That part of the gas bill is approved each year by the California Public Utilities Commission.

The cost of gas and transportation together make up 84 percent of the gas charges. Customers pay another 8 percent to subsidize poor people's gas bills, and SoCal Gas takes an 8 percent profit. Taxes and various fees go on top of all that.

Englander submitted a request Tuesday for his City Council colleagues to order up an investigation into the reasons for the higher bills. It would be up for a vote at a future council meeting.