Hurricanes Katrina and Rita were summer events, but their impact will probably be felt this winter.

And that impact will not just be on the Gulf Coast, but across the nation and on military installations as facility energy prices continue to increase, Air Force officials said.

The storms caused major damage to U.S. oil and natural gas production facilities. Now, concerns over increasing fuel prices and potential fuel shortages prompted the Air Force secretary to direct the service to begin additional energy conservation efforts last month.

“If, as expected, energy prices go up, the money is going to have to come from someplace,” said Gary Hein, Air Force energy team manager. “That someplace is the operating and maintenance budget. And that means mission impact, less construction or fewer services provided.”

Air Force facilities use about 78 trillion British thermal units of energy annually at a cost of about $800 million. That price tag could be significantly higher this winter, Air Force officials say.

“I’ve seen estimates of a possible 50 percent increase in energy costs, and in some cases 100 percent,” Mr. Hein said. “If even the conservative estimates come true, that could raise the Air Force’s energy bill to $1.2 billion.”

The Air Force has been a leader in energy conservation almost since the federally-mandated program came into being in the mid-70s. But easy fixes, like turning down the thermostat and changing light bulbs have already been incorporated into the service’s day-to-day culture. That means deeper, more personal sacrifices may be required.

“As the Air Force finds ways to conserve, so should our people,” said Col. Leslie Martin, of the Air Force Civil Engineer Support Agency. “Whether you are in the dorms, family housing or the office, turn lights off when you leave your area. Shut down equipment when you are not using it and let someone know if your building is too hot or cold.”