SACRAMENTO, Calif. -- Preliminary results from a study done by the California Energy Commission shows average fuel temperatures in the state are higher than the industry standard, appearing to lend credibility to complaints that vehicle owners are overpaying for diesel fuel and gasoline because of hidden "hot fuel" costs.
The study found that gasoline was being sold in California at an average year-round temperature of 72 degrees, which means drivers were getting almost 1 percent less than they paid for. Results for diesel fuel were similar.

Gasoline and diesel fuel expand as the temperature rises, approximately 1 percent for every 15 degrees Fahrenheit. A century-old industry standard fixes the assumed temperature at the point of sale at 60 degrees.

The California Energy Commission found that the average year-round temperature of gasoline sold in California is 72 degrees. Nationwide, if prices hold in the $4 range for the year, drivers will give up over $3 billion extra to hot fuel sales, according to one analysis.

"California has confirmed that fuel is routinely sold at temperatures high enough to short-change motorists year-round, and the same is true across the southern and southwestern U.S," said Judy Dugan, research director for the nonprofit Consumer Watchdog. "The weights and measures officials who should have fixed this years ago refuse to take their responsibility to consumers seriously. It's time for lawmakers to step in and end this ripoff."

The Partnership for Uniform Marketing Practices, a national coalition of associations representing independent petroleum marketers, warns against rushing to judgment on the need for automatic temperature compensation devices for fuel pumps.

PUMP contends there is no accurate or statistically reliable data to suggest that consumers are being adversely impacted under the existing system. Coalition members maintain that any variation from the 60-degree standard balances out for consumers based on year-round, seasonal averages. And, they say, installing temperature compensation devices is expensive and will likely raise the cost of fuel further.