"MOSCOW — Exxon Mobil won a coveted prize in the global petroleum industry Tuesday with an agreement to explore for oil in a Russian portion of the Arctic Ocean that is being opened for drilling even as Alaskan waters remain mostly off limits.

The agreement seemed to supersede a similar but failed deal that Russia's state oil company, Rosneft, reached with the British oil giant BP this year — with a few striking differences.

"The State Department gave a crucial green light on Friday to a proposed 1,711-mile pipeline that would carry heavy oil from oil sands in Canada across the Great Plains to terminals in Oklahoma and the Gulf Coast."

"A Senate bill that would allow energy-saving retrofits to be factors in mortgage underwriting has quickly attracted a diverse set of enthusiastic supporters that range from the conservative U.S. Chamber of Commerce to the liberal Center for American Progress.

"Lax trade restrictions and high sugar prices should allow the United States to overtake Brazil in ethanol exports during the second half of 2011, the U.S. Energy Information Administration said on Wednesday.

During the first five months of 2011 U.S. ethanol exports more than doubled from the same period last year, the EIA said.

"WASHINGTON — Federal geologists published new estimates this week for the amount of natural gas that exists in a giant rock formation known as the Marcellus Shale, which stretches from New York to Virginia.

The shale formation has about 84 trillion cubic feet of undiscovered, technically recoverable natural gas, according to the report from the United States Geological Survey. This is drastically lower than the 410 trillion cubic feet that was published earlier this year by the federal Energy Information Administration.

"Ten U.S. environmental groups came out in support of hundreds of protesters arrested at the White House since Saturday for opposing a proposed $7 billion pipeline that would greatly expand imports of crude extracted from Canadian oil sands."

The tar-sands oil entering the pipeline in Alberta contains a small amount of water. Whether this will cause corrosion of the pipeline is a question that has brought high emotions and little actual study.

"It would be natural to imagine that the fall of Tripoli would mean a significant decrease in the cost of oil and the pain that the average consumer feels at the pump. After all, in February, when unrest in Libya commenced, oil prices hit a two-year high. Libya is only the 15th biggest oil exporter in the world, but the oil it exports is of a particularly desirable type.