SAN FRANCISCO, Calif. — Environmentalists often call oil from Canada’s tar sands the dirtiest fuel on Earth, because the complex process of extracting it spews huge amounts of carbon dioxide into the air.
But by that standard, some of the crude oil pumped in California is just as dirty. In a few cases, it’s even worse.
Several California oil fields produce just as much carbon dioxide per barrel of oil as the tar sands do, state data show. A handful of fields yield even more.
All of them are fields that have been pumped for years and now need injections of steam to squeeze out more oil. Power plants create the steam, releasing greenhouse gases in the process. The gases build up in the atmosphere, slowly warming the globe.
In the past, few people knew or cared about the “carbon intensity” of California crude. Now, however, that intensity is helping fuel the fight over a key California policy to combat global warming.
The state’s “low carbon fuel standard” requires fuel producers to lower the carbon intensity of the products they sell here 10 percent by 2020. To comply, oil companies will probably have to blend more advanced biofuels into their gasoline and diesel.
But California refineries might also have to stop using some of the crude pumped here in the Golden State, according to an industry trade group.
That carbon-intensive oil would be exported abroad, while the state’s refineries would import more low-carbon oil to take its place. And since both the imports and exports would travel in ships – ships burning fuel and releasing carbon dioxide – the added maritime traffic could increase greenhouse gas emissions rather than cut them. The policy, in other words, could backfire.
“We call it crude oil shuffling,” said Gina Grey, vice president of strategic policy for the Western States Petroleum Association. “What’s the effect if we ship California crude oil to other countries and import low-carbon crude oil instead? Actually, that could increase emissions.”
Supporters of the fuel standard point out that most California oil fields aren’t as carbon intensive as the tar sands. And even at fields that require steam injection, oil companies have ways to lower carbon intensity by making their operations more efficient. Some companies – including Chevron Corp., which opposes the fuel standard – are even experimenting with using solar power to generate the steam.
Dirty oil sources
At the same time, environmentalists who back the fuel standard say California and the country as a whole need to pay more attention to the carbon intensity of different oil sources. Those sources that are dirtier than others, they say, should be discouraged for the sake of the planet.
The issue lies at the center of the ongoing struggle over the Keystone pipeline extension, which would bring synthetic oil from the tar sands to America’s Gulf Coast refineries. It’s also being studied by other states – such as Oregon and Washington -that are considering fuel standards of their own.
“There shouldn’t be an advantage given to domestic oil that’s high-carbon,” said Michael Marx, director of the Sierra Club’s Beyond Oil campaign. “That’s not to say we should lower our standards for the tar sands. We should raise our standards for domestic oil.”
Extracting oil from the tar sands is a difficult, multistep process that requires a lot of energy – so much that some companies have proposed building nuclear reactors to supply it. The sand is strip mined and mixed with warm water to separate hydrocarbons from the sand grains. The hydrocarbons are then processed into a kind of synthetic crude that can be piped to refineries.
California oil fields don’t require the same treatment. But after more than a century of production, many do need other forms of “enhanced oil recovery” to keep the crude flowing.