From powering airplanes to replacing nuclear energy, algae has been touted as a green energy miracle. So if our waterways are already filled with the stuff, why isn’t it filling the world’s skies with biofueled planes? Algae is a tricky creature that presents a lot of challenges and misconceptions. Here’s why it’s difficult to harness—and why it could big a big payoff.

Why Algae Is Awesome

As we previously reported, algae is a fuel source that’s vastly more eco-friendly than oil, and will be crucial as we head into a future filled with climate change and depleting fossil fuels.


In 2013, a paper published in the journal Bioresource Technology reported that algal fuels can cut carbon dioxide emissions by 50 to 70 percent. It’s also more efficient than other biofuels, like those derived from corn. The US Department of Energy says that algae could produce up to 60 times more fuel per acre than land-based plants.

Major corporations are starting to take note. In 2011, United Airlines made history with the world’s first algae-powered flight, transporting passengers from Chicago to Houston.


It’s even being eyed as a safer substitute for nuclear energy. In Fukushima—a place that’s all too familiar with the dangers of atomic power—a Japanese think tank is seeking to produce algae native to the region. Fukushima algae is apparently super tough and can survive harsh winters. That makes it a potentially hardy biofuel that’s local, has zero import costs, grows like weeds, and yields 60 times more oil per acre than corn.

Speaking of Japan: it’s one of the countries that’s aggressively pushing for microalgae production and its use as a fuel, especially for modes of transport, like cars, buses, and even jets. Japanese Prime Minister Shinzo Abe apparently named an algae biofuel company in Japan as his “favorite” startup.

That company, called Euglena, announced last week that it’s working with All Nippon Airways—Japan’s biggest airline—to use algae as plane fuel, and will open a demonstration plant in Yokohama. Euglena is spending 3 billion yen (around $25 million) to build the plant, which will produce over 33,000 gallons of algae a year.


Still, that’s a drop in the slimy green bucket. One Boeing 747 can burn that much fuel in a single ten-hour flight. That’s why coming up with a cheap way to mass-produce algae is so important. So can’t we just turn to one of our thousands of scum-filled rivers and strike green gold? Sadly, that’s just not how it works.

Researchers at Euglena Co. in Japan are working with All Nippon Airways and Chevron to produce microalgae as vehicle fuel. Credit: Akio Kon/Bloomberg via Getty Images

Algae Is Everywhere, But Not All Is Usable

You might’ve heard of these things called “algal blooms” in the news recently. That’s when algae spike in number in streams, rivers, ponds or lakes. Sometimes, that algae can be toxic to fish and other aquatic animals. These increases are called harmful algal blooms.



The Environmental Protection Agency says that in freshwater and saltwater environments alike, warmer temperatures could trigger more blooms of algae in these bodies of water.

Scientific American reported earlier this year that an increasing number of algae blooms have been found everywhere in the Western US, from Monterey Bay in California, all the way up to Alaska. These “unprecedented” algae blooms can harmfully impact local economies, especially in the fisheries industry. Plus, the blooms can suck oxygen out of the water, making it uninhabitable for life.

But wait, you say! We can put this algae to good use, right? Let’s scrape it out of all those ponds and fill 747 fuel tanks with ‘em! That’s a big misconception when it comes to algae as a biofuel. In reality, “algae” actually has an incredibly wide definition.


“Algae are actually an extremely diverse set of organisms and vary greatly in their characteristics,” the Department of Energy told me in an email. “Some are toxic and some are not, just as some plants are toxic and some are not. Strains selected for biofuel production are not toxic.”

The National Wildlife Foundation says that those algal blooms that we hear about in the news these days are often harmful. While teeny tiny algae plays a vital role in the aquatic food chain—phytoplankton serve as microscopic snacks for small animals called zooplankton—there are dangerous types, too. Cyanobacteria is a blue-green variety that can produce toxic chemicals capable of killing zooplankton, fish, and other water dwellers. Harmful algal blooms, or HABs, are often composed of cyanobacteria. And we can’t use that for producing biofuels.

And unfortunately, future Earth is going to see a lot more HABs. Climate change is to blame. It can lead to drought, which makes fresh water saltier, thereby triggering increased toxic algae. It also raises levels of worldwide carbon dioxide, which algae need to thrive. Finally, other environmental changes can occur, like changes in rainfall, a rise in sea level, and shifting patterns in how winds push water from the ocean to the shore. (There are manmade causes for HABs, as well, such as fertilizer runoff from farms.) All of these factors can lead to increased algal activity.



According to the National Wildlife Foundation, parts of the US have seen dizzying increases in annual precipitation—particularly the Northeast and England, where rainfall has increased a whopping 71 percent in the last 50 years. That’s led to these blossoming blue-green algae pools. Last August, a massive HAB in Lake Erie resulted in a temporary ban on drinking tap water in Toledo, Ohio, affecting 500,000 people for two days.

Okay, we get it. That’s pretty scary, but if not all algal blooms are harmful, isn’t there someway we can use all that algae floating around in the wild to good use? The answer is still tricky.

Microalgae for fuel is cultivated in big lab tanks like these, not scooped from algal booms in water bodies. Credit: Akio Kon/Bloomberg via Getty Images

To Use Algae as Fuel, We Grow It Ourselves

As an oil alternative that’s much better for the environment, algae is being seriously targeted across the world as a sustainable fuel source. However, unlike oil, we can’t just go out into the world and scoop it up. It needs to be raised in specific conditions. Otherwise, it’s too hard to collect.


“Even for blooms with large surface scums, as in Lake Erie, the bloom does not represent a large and dependable supply of algae which can be easily harvested,” said Quay Dortch of the National Oceanic and Atmospheric Administration. She’s the program coordinator of its HAB prevention and mitigation programs.

Besides sometimes being too toxic to use for biofuels, these big blooms in nature are also very dilute and quickly move up and down currents, making tracking them down in the first place a challenge. And most blooms only last for a short period in the growing season, Dortch said. The US Department of Energy agrees.


“Our office is not currently investing in the harvesting of algal blooms,” the DoE told Gizmodo in an email, “due to unpredictability of biomass and lipid composition and lack of co-location with conversion facilities when harvesting that biomass, which prevents it from being economical at the current time.”

Cylinders of microalgae sitting in a lab. Credit: Akio Kon/Bloomberg via Getty Images

What’s Being Done Right Now

So, how is algae being harvested as new fuel source? It sounds damn near impossible, based on all this algal bloom gloom and doom. It’s not—it just requires planning. Here’s what organizations are doing to tap algae, including the Department of Energy.


To ensure that the algae is both non-toxic and contained—the opposite of an HAB, basically—specific strands of microalgae are bred in big tubs in controlled facilities and labs. The University of California, San Diego has a whole division for algae growth: the California Center for Algae Biotechnology, which boasts 33,000 square feet of labs, 18 thousand-liter ponds, two 30-foot, 8,000-liter “raceway” ponds, and more. Scientists study the algae and figure out ways to best mass produce it as a sustainable source for fuel.

In those labs and in others like it (such as the Algae Program at the DoE’s Bioenergy Technologies Office), the real challenge is strain selection. That’s another difference between algae that’s bred to be suitable for biofuel, and the wild algae you might find in Lake Erie. Scientists are studying these microalgae in these controlled environments, trying to pinpoint which water and temperature conditions, for example, yield the most powerful strain of algae. From there, microalgae can be converted into biofuels.

Still, the biggest obstacle is economic feasibility. Algae is extremely expensive—but the DoE told me this summer that the goal is to get it down to $3 per gallon, which is on par with crude oil. That’s why that strain improvement process is so crucial: if researchers can find which energy-rich, robust, non-toxic microalgae types are best and how to grow those specific types quickly, they can scale that up to mass production.



The good news is that, unlike petroleum-based fuels, algae grows—fast. That’s one thing all algae has in common, whether it’s in a pond bloom or a lab tank.

They can double their number in an hour. Researchers want to use that to their advantage. That is, after all, part of the reason these algal blooms have slowly taken over our water supplies. But in this case, we want to figure out how to trigger algal spikes intentionally, in controlled environments, and with safe species of algae that are non-toxic and primed to pump out fuel.

Despite all the challenges and misconceptions, algae is being pursued by more and more governments, research centers, and corporations alike. Once we educate ourselves more on just how this process works, the green biofuels seems less pie-in-the-sky, and more plane-in-the-sky.


Top image: Sunlight from a solar collector at Utah State University’s Energy Laboratory shines through fiber optics to stimulate algae growth, seen here in 2009. Credit: AP Photo/Colin Braley

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