At issue during that hearing were $18 billion in tax breaks the oil companies are receiving over a 10-year period, making big oil a target for many politicians and environmental groups.
"While regular Americans are struggling to figure out how they are going to afford to drive to work and take their kids to school, oil companies are making record profits," said Kristina Johnson, a spokeswoman for the Sierra Club. "We need to stop subsidizing big oil. They are the last people who should be getting breaks from the government. American families need help, not big oil."
The House voted last year and again in February to end those tax breaks and, instead, use the money to support wind, solar and other renewable energy sources. But the measure has not passed the Senate, and President Bush has promised a veto, should it ever land on his desk.
Finding oil, extracting it from the ground and getting it to America is not cheap. That oil then needs to go through a very costly refining process to make it into the myriad of different gas and oil products U.S. consumer use. Crude oil is turned into everything from gas for cars, to oil to heat homes, to fuel for jet engines.
In order to produce all those types of oil products, the industry has pumped billions of dollars into its refineries. No new refineries have been built since 1976. But through expansions of existing facilities and technological upgrades, the industry has increased refining capacity by 20 percent since 1985 — and that's with 576 fewer refineries.
But that increase has not kept up with gasoline demand, which has jumped 23 percent since 1990, according to the Energy Information Administration.
Critics say the industry hasn't done enough to expand refineries and other parts of its infrastructure. They also say that the companies could spend more on exploration and buy back less of their companies' stock, something that props up the share price
Oil refineries are not always profitable and are often a reminder of the risks in the business.
This week Valero Energy, the largest U.S. oil refiner, posted sharply lower quarterly earnings. That's right — when BP and Royal Dutch Shell reported big earnings, Valero showed signs of struggling, with earnings of $261 million. The reason: very narrow margins in the refining process, as crude oil prices rose even faster than gas at the pump, and losses from unplanned outages at its refineries.
While crude oil has gone up from about $66 a barrel to almost $119 — an 80 percent increase during the last year — gas has gone from $2.71 a gallon to $3.60, an increase of only 33 percent.
That may not seem like such a small number to someone filling up a gas tank, but for an oil refiner, that difference takes a major bite out of profits.
Refining is just one aspect of the business for most oil companies, and any losses there are more than made up by profits from the actual extraction and sale of oil.
As for who reaps the biggest reward from these massive quarterly oil profits, many people may imagine a group of oil privileged executives or tycoons. And they do own millions of dollars in stock, but nothing compared to what the rest of the public owns.
For instance, Rex W. Tillerson, chairman and CEO of ExxonMobil, owns more than 900,000 shares of his company's stock, worth more than $84 million, according to SEC filings.