Wine packaging continues to trend toward lighter-weight glass, particularly at a time of cost-cutting and rising energy prices.

Transporting glass in addition to wine became a financial as well as environmental concern in 2008 as fuel prices spiked and trucking companies tacked on surcharges. Now uncertainty about global petroleum supplies has sent fuel prices in the U.S. to nearly $4 a gallon, with some predicting it could go as high as $5 this year.

Ohio-based global glass giant O-I has expanded its line of less-hefty 750-milliliter wine bottles, adding a 14-ounce option to a range of Claret- and Burgundy-style containers.

It's part of the company's "Lean + Green" program to reduce the amount of energy needed to make and move bottles.

“The lean and green bottles have less impact on the environment and use less energy and raw materials for manufacturing,” said Stan Gossett, vice president and North America wine category director for O-I.

Glass plants consume large amounts of energy to liquefy raw materials into glass. Such operations are coming under increasing federal and state scrutiny in efforts to reduce greenhouse gasses blamed for climate change.

Made at O-I's California plants in Oakland and Tracy, the lighter wine bottles were first released last May in weights ranging from 11.6 ounces to 1 pound, or 16 percent to 27 percent lighter than comparable containers.

Lightening the load is a tricky design challenge, according to O-I.

Thinner bottle walls or changes in glass composition could create costly bottling-line delays from breakage. Removing or reducing the punt -- the traditional bottle-bottom thumb grip -- can create challenges for marketing to consumers who associate deep punts with high-quality wines.

For example, O-I pulled the punt to reduce the weight of bottles for Fezter Vineyards of Hopland.