One of global warming’s biggest culprits is the American automobile. The United States produces a quarter of the world’s greenhouse gas emissions, and about a third of that comes from transportation. If we want to cut carbon, we’ll have to choke it at the tailpipe. But how?
America has tried, with increasing earnestness, to reduce its gasoline habit—first through greater fuel efficiency, more recently via “first generation” biofuels, such as corn-based ethanol, intended to replace petroleum with plant power. But critics spar over the carbon economics of using crops—particularly corn—as biofuel feedstocks. Growing corn requires irrigation and fertilizer, says Dan Kammen, director of UC Berkeley’s Renewable and Appropriate Energy Lab, who has analyzed the environmental merits of different fuels. “If you added up all these fossil-based inputs, corn ethanol was at best a very mild improvement over gasoline,” he says.
Corn ethanol also raises the “indirect land use” conundrum—when farms are switched from food to fuel production, virgin land elsewhere must be cultivated to meet the world’s unrelenting demand for food. Cutting down native forests, which recycle carbon dioxide into oxygen, boosts the need for yet more fertilizer and irrigation, exacerbating global warming. “If a farmer chooses to stop growing food and start growing a biofuel, or chooses to bring new land into production because the market for biofuels is growing, that comes with a carbon penalty, and sometimes that penalty alone can actually be worse than gasoline,”
Some have advocated chucking liquid fuels altogether for electric batteries or hydrogen fuel cells. But even if you skip the debate over the eco-merits of plug-in cars—electricity is only as “green” as the power plant that makes it—or the technological challenge of developing long-lasting batteries that don’t cost a fortune or weigh a ton, these technologies still face infrastructure problems. We have trillions of dollars worth of vehicles, filling stations, and refineries built to accommodate liquid fuel. Creating a new fleet of vehicles and a system for recharging batteries or swapping fuel cells will take money and time, a luxury
we may no longer have.
That’s why the search is on for a second generation of biofuels derived from plants that don’t compete for cropland. Fuels made from farm waste itself—like bagasse, the material that remains after pressing sugarcane, or corn stover, its leftover stalks and
leaves—have won fans. But those still have ties to agriculture and are subject to its geographic and seasonal limitations.
Now, a cadre of California companies believe the solution to this complicated problem is really simple. Like, single-cell simple. Could the fuel of the future come from the most ancient green thing of all: algae?
Cell biologist Stephen Mayfield has spent the last 25 years working with algae, much of it at the Scripps Research Institute in La Jolla, California, and most of that manipulating it into making medically useful proteins: one that neutralizes anthrax, one that
fights cancer, one that’s part of an anti-malaria vaccine. But a few years ago, a venture capital firm eyeing an even bigger health problem asked him to turn algae into biofuel.
This wasn’t as far-out as it sounds. “We knew that algae could make biofuels, that’s been known for a long time,” says Mayfield. Algae naturally make oil, or lipid—it’s how they store their energy. This oil can be converted into fuels that can be used by today’s vehicles: diesel, biodiesel, gasoline, even jet fuel. Yet until recently, not many companies had tried to do it.
Mayfield thinks that a few years ago, the algae idea finally reached the tipping point. “The driving force on this has been a combination of things: climate change, global warming. People began to say ‘Hey, we have got to start taking this biofuel stuff seriously, we cannot continue to burn fossil fuel and just spew the CO2 into the atmosphere,’” he says. Add to that the price of gas skyrocketing and “the realization that we are buying most of our oil from countries that really don’t particularly like us,” he says, and Americans warmed to energy independence—that is, growing our fuel at home.
Algae’s number one selling point is that among its untold thousands of species there’s bound to be one that can hack it just about anywhere, and nearly all of them are incredibly low-maintenance. Algae can grow in the ocean, in indoor tanks, in open ponds, or in translucent tubes called “photobioreactors.” These last two can be arrayed in the desert to catch the sunlight, built on barren land of little use to farmers. Better yet, algae doesn’t mind its water brackish or filthy, and can be grown using seawater, municipal wastewater, agricultural runoff, or the water from saline aquifers.
Compared to other biofuel feedstocks, algae are prolific oil makers. Depending on who you ask, photosynthetic
algae can produce anywhere from 2,000 to 5,000 gallons per acre each year. Corn, by comparison, produces closer to 250 gallons and sugarcane produces 450. That’s largely because all that algae does is grow more algae. “They’re not making roots, they’re not making flowers, they’re not making trunks, they’re not doing all the other things that higher plants do. They’re just doing photosynthesis,” says Mayfield. Algae can also be grown year-round. Compared to corn’s four-month growing season, algae is a little green workhorse.
Perhaps best of all from a global warming standpoint, photosynthetic algae suck up the greenhouse gas carbon dioxide. In fact, the massive algae population floating around the Earth’s waterways for the last 3 billion years is largely responsible for the fact that we have a temperate, oxygen-rich climate at all. “It’s unarguable that if we did not have oceans full of algae-sequestering CO2 we’d be in a completely different place than we are now,” says Mayfield of the role algae plays in climate regulation. “So already it does that. We just need to get it to do more of it.”
Mayfield now chairs the scientific advisory board at Sapphire Energy, an algae biofuels company he helped found in 2007. While the company is headquartered in San Diego, its algae resides in Las Cruces, New Mexico in a set of ring-shaped pools; a paddle wheel keeps the bright green sludge swirling through it. After four to fifteen days in the pool, the algae is harvested—or, “dewatered”—and the oil is transformed into what the company calls “Green Crude,” which can be refined into gasoline, diesel or jet fuel.
While burning algae oil does produce greenhouse gasses, Tim Zenk, Sapphire’s VP of corporate affairs, points out that because twelve to fourteen kilograms of CO2 are consumed to make every gallon of algae oil, the net emissions are low. “Sapphire‘s Green Crude fuel has a life cycle carbon impact that is roughly seventy percent less than petroleum-based fuels, and significantly lower than other conventional biofuels,” he says.
While Las Cruces is only a demonstration site, Zenk says the company expects to operate at commercial scale—producing 1 million gallons of fuel—by the year 2012, and be up to 1 billion by the year 2025. Ultimately,
Sapphire hopes to provide three percent of the 36 billion gallons of renewable fuels the Environmental Protection Agency says must be integrated with the nation’s motor-fuel supply by the year 2022.
Other California companies are hoping to dip a toe into this 36-billion-gallon market. Alameda-based Aurora Biofuels, founded by a trio of UC Berkeley grads in 2006, is using a similar model of open saltwater ponds. Although Aurora currently only runs a small pilot plant in Florida, CEO Bob Walsh says that by next summer they’ll have opened a demonstration site producing about 100 gallons a day, and that ultimately they’ll roll out facilities worldwide, each producing between 60 and 100 million gallons a year.
Solazyme, in South San Francisco, also hopes to eventually produce billions of gallons annually; it can already make batches of oil on demand and even boasts an algae-powered Mercedes. In 2008, the company signed a biodiesel development and
testing agreement with Richmond-based oil company Chevron.
Meanwhile, La Jolla-based Synthetic Genomics, headed by J. Craig Venter, the biologist most famous for his role in sequencing the human genome, recently announced a $600 million joint venture with ExxonMobil to develop algae fuel. The company will use both ponds and photobioreactor tubes.
While it may seem odd that alt-fuels companies are partnering with the petroleum producers whose business they are ostensibly trying to undercut, the oil giants have a couple of things that algae producers need: gas stations and waste CO2. Let’s take the carbon first: While algae can absorb it from the atmosphere, it’s more efficient to directly shunt it from the smokestack of a power plant, refinery, or steel mill into an algae pond. “You pipe it over and you pump it in, like they add CO2 to Coca-Cola,” says Aurora CEO Walsh.
Sapphire Energy, for example, is currently buying its carbon but would like to partner with a refinery or utility, a move that would make production greener for both companies. “We beneficially reuse the CO2 burned in a coal-fired power plant or emitted from an industrial source, resulting in green electricity and displacing the need for crude oil from the ground,” says Zenk. “The end result is a two-to-one reduction in CO2 emitted into the atmosphere.”
Zenk says Sapphire is also considering a “closed loop” system in which the solids left over after dewatering
the algae would be put into anaerobic digesters to produce methane, which in turn could generate electricity for the facility and produce CO2 to be pumped back into the ponds.
Additionally, the oil giants already have distribution systems for getting fuel to the pump, including their own filling stations, something the smaller fuel makers don’t want to have to replicate—or compete with. “To go further downstream you’ve got to push someone out, so we’d rather just fit in, let the existing infrastructure move it to the marketplace,” says Walsh.
Ultimately, some algae companies want to lean on the expertise of those who have been in the fuel business longer. “We will never refine oil into diesel fuel cheaper or more effectively than a major oil company; they have a hundred years of experience at doing that and they own factories that are the biggest industrial facilities in the world,” says Harrison Dillon, president and CTO of Solazyme. “You hear people at conferences saying ‘We’re going to put Big Oil out of business,’ and when you hear that that’s when you know that you’re listening to somebody who hasn’t really been in this very long. That kind of thing just isn’t going to happen.”
At six years old, Solazyme is one of the algae industry’s eldest, and perhaps most commercially advanced, players. “We founded the company in 2003—this was in the Stone Ages of biofuels,” recalls Dillon. “We couldn’t find a venture capital firm that had even heard of the concept of a biofuel in 2003, which sounds amazing.”
Solazyme started out planning to grow photosynthetic algae in ponds or photobioreactors, but soured on the idea, deciding that ponds are too costly and can’t produce enough algae. “It takes a couple of months to get an algae culture up to density, and you still then get, if you’re lucky, maybe a gram of algae per meter of culture,” says Dillon. “And that one gram of algae is like ten percent oil. You’re talking about an enormously expensive process to make a gallon of oil.”
Instead, Solazyme began experimenting with species that could grow inside fermentation tanks. Growing
indoors has its advantages: tanks are cheaper than ponds, and Solazyme found it could control the algae’s environment to get it to produce a very high quantity of lipid—as much as 75 percent of the cells’ dry weight. Says Dillon, “It’s about three decimal points cheaper per gallon” to grow in a tank than in a pond.
Instead of sunlight, these algae are fed a carbohydrate-rich diet of, essentially, trash. “Algae has been evolving for a long time in the presence of a lot of rotting plant material and it’s made certain species very adept at using any organic material that’s available to them,” says Dillon. A laboratory on the Solazyme campus is used to test-feed foods to algae strains, to see what will make each grow best. Among the candidates: corn stover, molasses (a byproduct of sugarcane processing), municipal green waste like grass clippings, even the waste glycerol produced when making biodiesel.
Having a variety of feedstocks is important, because Solazyme envisions manufacturing oil via a network of facilities, each using strains of algae that eat whatever happens to grow nearby. “If it’s in the Pacific Northwest, for example, it’s probably going to be lumber waste,” says Dillon. “If it’s, say, in the Midwest, agricultural residue, things like corn stover or other stalks and leaves from the plants. If it’s in a place like Florida or Hawaii, it could be sugarcane.”
Solazyme has already whipped up a few flavors of oil. Its office space, built into a former ice cream factory,
features an enormous glassed-in refrigeration bay now housing an assortment of plastic drums and buckets—
the oil in this one might be more suited for making jet fuel, Dillon says pointing, or that one for diesel.
Upstairs in a conference room, Dillon provides a glimpse of what’s inside those barrels, hefting three large glass jugs onto the table. The first contains diesel; it’s clear and gives off a faint, waxy smell. “Kind of like paraffin,” Dillon suggests, screwing the cap back on. There’s also biodiesel the shade of maple syrup, and crude algal oil, a deeper and more viscous orange, which emits a slightly soggier funk.
“We are the first and only company that has made algal fuel at a commercial scale,” says Dillon, indicating the jugs. “That’s probably more oil than any algae company you would go to talk to has ever made, and that’s a prop in our conference room.” To date Solazyme has made more than 10,000 gallons of algae oil; Dillon attributes this productivity to greater efficiency, and the fact that growing in tanks allows the company to produce batches on demand in less than a week.
There’s one more oil sample in the room, and it’s a hint that Solazyme is eyeing a market other than transportation.
Like the rest, the pale yellow fluid in this tiny vial started off as something inedible like sawdust or corn stover, before being fed to a tank of algae and turned into lipid. Now it’s cooking oil, surprisingly light on the tongue and almost flavorless. Branching out into food oil may be a smart move. Instead of having to beat the cost of gasoline, which is currently under $4 a gallon, “The wholesale price of olive oil is in, say, the $15 to 18 a gallon range,” says Dillon. “In fact, we are well below that manufacturing cost.”
Ultimately, Solazyme plans to take its oil-making technology far and wide, hoping that algae oil could be as integral to manufacturing as petroleum is today. “If you think about everything in your house that is made out of oil, it’s not just the gas in your car,” says Dillon. “It’s the cleaning supplies under the sink, and plastics and cosmetic ingredients, and the oil in your salad dressing bottle.” The FDA is currently reviewing Solazyme’s cooking oil; Dillon suggests that it may beat the company’s algae fuel to the marketplace.
Making algae oil affordable is probably the biggest challenge ahead for the fledgling industry. “Ultimately if you’re going to have a market for it, it needs to be cheaper than gasoline,” says Lawrence Berkeley National Lab Earth scientist Nigel Quinn, who is studying the state of algae fuel technology for Berkeley’s Energy Biosciences Institute. But currently, he says, the cost of producing algae in open ponds is five to ten times the cost of cost of producing a fossil fuel.
Most companies estimate they’ll need to get into the $60/barrel range before algae-based fuel finds your gas tank. A few are hoping that the military, which can afford to pay more for state-of-the-art technology, will be an early adopter, or that the trucking, cargo shipping, and aviation industries will take an interest. Sapphire, for example, has already tested its jet fuel for two airlines, JAL and Continental.
But building an algae industry from scratch won’t be cheap. Large tracts of land—even barren land—are expensive, and so are ponds and photobioreactors. A few farms already exist, but most grow the kind of algae used in health food supplements, not for oil, so there’s not a farming community hoping to adapt its crop for the biofuel market, as there is with corn, soy, and sugarcane. (Consequently, there’s also no algae lobby pressing the government for support.)
Co-locating with big carbon producers will help drive down manufacturing costs, says Quinn, and so will coming up with sellable byproducts. “We’ve only just scratched the surface in terms of what those products might be,” he says. A few companies plan to sell the dried-out meal that’s left after dewatering the algae for use as animal feed. Others hope the cosmetics and plastics industries will also buy their oil, or that they can collaborate with wastewater treatment plants.
Solazyme has a jump-start on the cooking oil market, and Dillon is quick to point out that its food oil won’t be made from genetically engineered algae strains. But all of the companies mentioned in this story expect to use some form of genetic modification to select for desirable qualities like hardiness and productivity when cultivating algae for fuel, and genetic modification is likely to be a serious point of debate as the public weighs the environmental desirability of algae oil.
The companies planning to grow in outdoor ponds know they’ll face some skepticism about the risk of the engineered species contaminating the surrounding gene pool. They contend that the odds of their genetically modified algae taking over the local waterways are eclipsed by the odds of hardier wild creatures getting in and overrunning the tanks, especially since the algae will be engineered to overproduce lipid—in other words, to be attractively plump to predators. “If you take an algae and convert it into something that makes thirty percent fat, that means it is ready to be eaten by everybody else out in the real world,” says Mayfield. “Escape—although it is something that we have to be very careful of and we want to be very conscious of—I think in the end is not a real problem.”
Some observers agree that the chance of genetic contamination is probably low. “Because those organisms would be in tanks, presumably on some piece of desert land or in a parking lot, if those are just spilled that doesn’t strike me as a high risk,” says UC Berkeley’s Dan Kammen, although he is more leery of farming algae in the ocean. “We can’t even keep our genetically modified salmon in pens, let alone algae that can float anywhere,” he says. As for Quinn, he says that even if genetically modified algae is unlikely to grow well enough to out-compete native species, it would be best kept in closed systems like photobioreactors, if only to avoid worrying the public.
Ultimately algae’s biggest question mark—but perhaps also its biggest promise—is that although it is 3 billion years old, there’s still so much left to learn about it. Of its thousands of species, only a few have been extensively studied, and even fewer genetically sequenced. Bioprospectors hoping to isolate species that might be good oil producers have their work cut out for them. Just as mankind couldn’t have tamed corn without the plow, or cotton without the gin, this new industry will need what Mayfield dubs an “algae combine,” new technologies that will make harvesting fast and cheap.
But even if the algae fuel industry is currently very small, innovators like Mayfield believe that they’re on the cusp of a new kind of green revolution. “Right now we have maybe 200 acres total in this country, maybe 300 acres of algae growing,” he says. “So we have got to learn as a society how to do this. We’ve done it in corn—we have 90 million acres of corn. Soybeans, 56 million acres. Okay, we can do it. But we’re not there yet.”