Utah's oil refineries are to blame for the state's relatively high gas prices, according to a group that represents gasoline retailers.

"The refinery dictates the price," said John Hill, executive director of the Utah Petroleum Marketers and Retailers Association.

Hill said five refineries provide a majority of the gasoline purchased by Utahns. Three of those refineries, he added, have been "down" recently for maintenance.

Hill said when a refinery is down, or producing less gasoline than normal, its customers — gas stations and convenience stores — are allocated less than their normal supply. When supply can't keep up with demand, the prices go up or stay up while elsewhere in the country they're falling, according to Hill.

Another reason a refinery may be temporarily down, he added, is because it is changing the grade of gasoline it produces from a summer grade to a winter grade, adjusting for its ability to perform in differing temperature and moisture conditions. Hill said those changes take place in the spring and fall.

With summer almost over — and higher volume travel days gone — AAA Utah this week reported the national average of gas at the pump is at $2.61 per gallon, compared to $2.94 per gallon in Utah, which is the fifth highest in the United States, according to AAA's report.

Some Utah consumers are tired of the same answers — high demand, lower supply — for higher gas prices.

"Simple corporate greed seems the most likely answer," said Alpine resident Stephen Crain in an e-mail to the Deseret Morning News. He cast blame on wholesalers and retailers.

Frequent diesel user and retiree Brad Merritt, of Woodland Hills, said he has sat at home this summer with his "fifth wheel" because of the high price of diesel.

"Personally, I think the oil companies saw an opportunity to increase their profit margins and are gouging us," he said about how normally lower diesel prices — compared to regular gas — are rising above already high gasoline tabs.

Hill said one Utah refinery recently dropped its price of diesel by 20 cents to its distributors and that a similar reaction with gasoline throughout Utah should take place.

"We should see in the next couple of weeks our prices coming down," he said. "I'm hoping we'll see $2.19 (per gallon) by Thanksgiving," if there is no major crisis in the international oil market.

"I don't have a crystal ball — it's just wishful thinking," Hill added. He said he based his wish on trends and what national analysts are predicting, which is a drop in gas prices across the nation.

Over the past year, gas prices in Utah have been like a yo-yo, with among the lowest prices in the nation last winter to among the highest in the nation last October, when AAA reported that a gallon of gas in Salt Lake City cost $2.62, compared to $2.19 in Kansas City, Mo., $2.27 in Minneapolis and the national average of $2.59.