President Bush ordered the government this week to purchase hybrid-powered vehicles and reduce the federal fleet's petroleum consumption by 2 percent each year through 2015, according to the Los Angeles Times. The president's order, consolidating earlier ones while setting new goals, also directs the federal government to reduce "energy intensity," a measure of its consumption, by 3 percent a year by 2015, in an effort to restrict the emission of the gases linked to global warming. His executive order is intended to put the federal government, which Bush noted operates the nation's largest automobile fleet, in the position of trying to lead by example, White House officials said. Bush said the government was being directed to purchase plug-in hybrid vehicles, which he said could be driven 20 miles before their batteries were drained and the engines needed to switch over to more conventional power, the Los Angeles Times reports. But he said the purchases only could be made when the vehicles are commercially available. He said, however, that the potential federal market for such cars might increase the confidence of automobile manufacturers that a market for such new technology products could be developed, thus making them more commercially viable.