Washington: Le Diplomate had an emergency. After a week of frying frites, the kitchen at Washington’s famous standby for French cuisine was full to bursting with used grease.
Two waist-high storage tanks in the back of the restaurant sloshed to the brim with dark, viscous oil. During the weekend rush, the staff stored some of the spent grease in plastic tubs, but they were quickly running out of places to put it.
Restaurants are prohibited from dumping grease down the drain because it would clog city sewers. So on a Tuesday afternoon, James Howell nimbly backed his truck into an alley behind Le Diplomate. He hopped down from the cab and snaked a rubber hose to the kitchen. Then with the flip of a switch and a loud drone, the hose slurped the used cooking oil into the truck’s gleaming steel 2,200-gallon tank.
The spent grease that restaurants unload as waste has become a valuable commodity. If you’ve been on a plane lately, there’s a chance that used cooking oil has helped launch you into the sky. Refineries recycle waste oil into kerosene pure enough to power a Boeing 777. The process is expensive - but it can create 70 to 80 percent less planet-warming pollution than making jet fuel out of crude oil, experts say.
Last year, airlines burned 340 million gallons of sustainable aviation fuel (SAF) - nearly all of it made from used cooking oil or animal fat leftover from meat packaging.
That’s a drop in the bucket compared to the 114 billion gallons of fuel airlines burned overall, which create 2.5 percent of humanity’s carbon pollution, according to the International Energy Agency. But airlines have vowed to use much more SAF to lower their greenhouse emissions. European regulators have set strict rules requiring airlines to use more SAF over time, while US regulators dole out tax credits to coax companies into buying it.
This is the airlines’ main plan for dealing with their greenhouse emissions. Upgrading new planes with more efficient engines helps a little. And, one day, planes may run on electric batteries or hydrogen fuel cells - but those are still decades away and may never work for long flights. To manage most of their climate impact for the foreseeable future, airlines are betting everything on alternative fuels.
“Ninety-eight percent of [our greenhouse emissions] come from the fuel we burn,” said Lauren Riley, chief sustainability officer at United Airlines. “We’ll continue to look everywhere we can around technology and innovation of the aircraft itself and the engine, but we have to look at replacing our fuel.” Experts say this plan can work, but it’ll require fuel refiners to dramatically raise SAF production and find new raw materials besides old cooking oil to turn into kerosene. Depending on what they use and how they refine it, this new class of fuel could make flying more sustainable or cause a whole new set of environmental headaches.
Turning fat into fuel keeps grease out of the landfill and petroleum in the ground. The demand, though, has begun to outstrip the supply. — The Washington Post
