Fifty dollars can buy fifty cheeseburgers, a textbook, a pair of Nikes – or these days, one tank of gas.

According to gasbuddy.com, a site that tracks gas prices across the country, going to the gas tank costs more than it has in nearly three years. San Francisco has the highest prices in the U.S. with an average cost of $3.94 per gallon.

Many drivers blame the political turmoil in the North African country of Libya.

“A lot of it is due to tension in the Middle East, particularly what is going on in Libya, which produces around 2 percent of world oil,” said Phillip King, SF State associate professor of economics.  “Many of the people in Libyan oil fields are foreign and they’ve left, and a lot of the oil wells are shutting down or will shut down.”

King also attributes high gas prices to tension in countries in the Middle East.

“Markets worried about Saudi Arabia and tensions in Iraq and Iran are also making the price increase,” he said.

Although the U.S. is experiencing high gas prices, Europe is more severely impacted.

“Most of the oil in the U.S. is based from West Texas Intermediate, and Libya supplies Europe and European countries,” King said.

As for the reason why SF experiences the highest gas prices in the country, King said it is due to a limited number of refineries and higher environmental regulations in California.

“We are one of the most expensive cities in the U.S. and we have a limited number of refineries,” he said.

Senior petroleum analyst Patrick DeHaan of gasbuddy.com also attributes high gas prices to tension in the Middle East.

“There is concern that unrest in the region could impact Saudi Arabia and it can have an impact on oil supply,” DeHaan said.

DeHaan, who has worked with gasbuddy.com since 2009, has been forecasting gas prices since 2005. He said that because summertime is approaching, more people will be driving, which allows oil companies to increase prices and make more profit.

“California has strict environmental air pollution standards and so the type of gasoline is among the most stringent in regards to air pollution standards than anywhere else in the entire country, which is more expensive,” DeHaan said.

The increase in gas prices has affected local gas stations, according to Mission Street Chevron General Manager Steve Matijevich.

“We’re experiencing a decrease in the number of customers that are buying gas and washing their cars,” Matijevich said.

According to the historical price chart on gasbuddy.com, the last time gas was this expensive was in 2008. At that time, gas reached its all-time high of $4.61.

Increased gas prices means change of transportation methods for some consumers.

“If it reaches $5, I’m not going to be driving as much,” said Jessica Kim, 20, an SF State civil engineering major. “I’ll definitely ride my bike more often and utilize public transportation when I’m in the city.”