Algae as Energy: A Look to the Future

Energy Crisis. Oil Shortage. Sticker shock at the pump. We are all aware of the fact that the world’s oil reserves, all 3 trillion gallons of it, will one day be used up. And, at the rate the world consumes energy, this day is coming fast.

image of high gas prices

So, what do we do about it? One way in which humanity is beginning to deal with dwindling energy reserves is by accessing biomass fuels. These fuels, such as algae, are made through a process similar to the conversion of oil from organic materials. The main difference is that biomass fuels take days instead of millions of years. This potential for rapid production, combined with the potential to produce an infinite amount of biomass, leads to a theoretically infinite energy source.

chart of algae life cycle

There are, of course, several key issues surrounding this fuel source. The first is a concept called Energy Return on Energy Invested (EROI). This concept deals with the economics of producing a specific type of energy, and is expressed as a ratio.

chart of exajoules of energy

On this graph “biodiesel and gasahol” does not include algae biofuels, but rather corn, soy and other crops.

Right now, conventional oil reigns supreme, topping out with a ratio of 100 BTU of energy produced for every 1 spent. At its most energy-intensive, conventional oil is 15:1. Currently, the EROI for algae-based biofuel is 1.06:1, or barely efficient. This comes from the massive cost needed to start and maintain the crop, as well as to convert the crop into oil.

chart showing conversion of algae to biodiesel

The fourth and fifth steps in this process are the most energy-intensive, as they require purchase (and thus manufacture of) solvents, as well as heating elements to dry them.

When coupled with a price of $33 per gallon, biomass fuels seem unfeasible. The other challenge to the fuel is that in the wild, algae do not produce the massive lipid content needed to obtain an efficient transfer into oil.

So how do we overcome these difficulties, and should we even try? The answer is yes to both. Mankind has faced many difficult problems in the past, and has always come up with a solution. For example, there was a time when we were just as afraid of fire as the next animal. And yet, we not only figured out how to control a fire once it was started, we figured out how to start our own, and to use it as a tool.

primtive man setting fires

Man using fire to drive game. Much easier than running.

Now, the only challenge before us is that we are running out of our favorite fuel to burn, and must look for alternative. Even now in the world of biofuel, there are people solving these problems. For example, the issue of a low EROI is being addressed by researchers at Pacific Northwest National Laboratory, who recently patented a process that converts algae to bio-crude in an hour with a 50% return. Their process also eliminates the drying and chemical extraction processes, two of the largest roadblocks to producing biofuel from algae.

image of scientists with their lab work

An upstart company called Culture Fuels is developing a more efficient growing system that uses partially submerged plastic bags, pumped full of a nutrients and CO2-rich slurry. This system combines open field propagation, which is relatively cheap despite the large area required, and closed bioreaction, which allows for control over invasive species. The researchers also claim that the system can be used in a “semi-continuous” manner, harvesting 60% of the crop every 6 days. In the system below, the total yield is 2500 liters of algae slurry.

a pond growing algae slurry

To combat the relatively low presence of lipids in the individual organisms, companies such as Solazyme Inc. are experimenting with selective breeding, genetic modification and fermentation processes to increase the yield.


n the end, algae-advocate groups hope to make biomass fuels down to conventional gas prices, somewhere between $1.50 and $3.50. Achieving a lower price would allow for these cleaner fuels to have a huge competitive advantage over conventional fuels. 

Transportation fuels

Another big advantage is that algae feeds on the toxins produced in manufacturing. This means that this new fuel source mankind can both reduce the amount of toxicity in the environment while also helping clean up toxins already present.  El Dorado Biofuels LLC is already utilizing algae's cleansing properties by using wastewater from oil production. As of 2011, they were working with Fulfer Oil and Cattle LLC, an equally small startup oil company. The president, says that “I end up with about 100 barrels of water for each barrel of oil I produce. I usually just inject it back into the oil formation, but that’s very costly. It would be a big help if I can send it to an algae plant instead” [4]. According to the Natural Energy Technology Laboratory of the Department of Energy, Fulfer’s business and other small operations in his county produce an average of 400 million barrels of wastewater per year. At a cost of $1-$3.50 per barrel to bury it, the cost in money alone is tremendous. Add to the equation the fact that there is little to no data on exactly what this water contains, and the potential for a major environmental disaster becomes apparent if not disposed of properly.













Photos 1,5,6: Creative Commons

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Brant Phillips

Last Updated: April 25, 2018