Gasoline prices have been shooting up in South Florida but there's still once energy bargain: Electricity.

Households in Broward and Miami-Dade counties paid an average 11 percent less for electricity last month than the national average, the U.S. Bureau of Labor Statistics reported Tuesday.

South Florida homes were charged 12 cents per kWh in March compared to the nation's average of 13.5 cents per kWh, according to the federal agency that monitors consumer prices.

Electricity in South Florida is almost half the price of San Francisco's, said BLS economist Steve Rondone. South Florida also boasts cheaper electricity than many other major cities, including Houston, Detroit, Los Angeles, Boston and New York, he said.

"South Florida is much more reasonably priced when it comes to electricity," the economist said, attributing it to the region's main supplier, Florida Power & Electric, recently switching over to cleaner, cheaper natural gas to fuel its plants.

FPL bills have actually gone down about seven percent in the last five years thanks to the switch to natural gas, said utility spokeswoman Alys Daly.

"Every penny FPL saves is a penny the customer saves," she said.

A year ago in March, households in the two counties spent 10.2 percent less for electricity than the national average. South Florida consumers have been paying at least 10 percent less for electricity than the national average for the last five years, the bureau said.

Meanwhile, rising gas prices averaged $3.664 a gallon in the Miami-Fort Lauderdale area last month -- but were still down 23.7 cents from the average $3.901 per gallon from a year ago, said BLS Regional Commissioner Janet S. Rankin in a statement.

However, gas prices have continued to rise  this month --  the price of regular gas in Broward County averaged $3.82 per gallon, up 8 cents from last week and up 22 cents from a year ago, according to the travel club AAA. The price in Palm Beach County averaged $3.86 per gallon, up 7 cents from a week ago and up 19 cents from a year earlier.

Last month, South Florida drivers paid a little bit more for gas than the national average, about 6 cents more a gallon.

dgehrke@tribune.com or Twitter @donnagehrke