It was a sunny Wednesday morning, unusually warm for late November. The man in the crowded subway train held his brief tightly against his chest. Inside, the work he had exhaustively done over the past ten years weighted heavily on his hands. It was the day he much expected, with equal amounts of hope and angst. He got out of the underground station and quickly made his way through the busy sidewalks of his city, zipping through people and cars. He was in a hurry, and did not want to be late. From the distance, he saw the bright lights of his destination, the Blue Sky Capitalist Ventures – the main startup investors in town. He felt a drop of sweat running down his forehead as he entered the building. “Are you the 9 o’clock?”, said the receptionist. Jitters stopped him from answering, so he just confirmed with a nod. “Very well, please follow me”.
He followed the receptionist through the hallways, finally reaching a conference room. Across the long table, a group of five people stared him down - he was sure they could notice the coffee stain on his tie or how his black shoes did not match his navy pants. The doors closed behind him, and the women sitting at the table head said in a severe tone, “You have thirty minutes”.
He took a deep breath, and started nervously.
“Hello, I am Dr. Green and today I present you my latest project, which I believe will change the way you drive your car or turn on a lightbulb”.
He waited for a nod of approval, which never happened. He then continued, in a well-rehearsed monologue.
“As it became evident over the past couple decades, humans are causing irreversible damage to the planet. It is our duty to investigate and find manners to stop the destruction of our home. I believe that reducing the use of energy from fossil fuels, or stop relying on them completely, is a much-needed necessity. From all the alternatives, biofuels might be our best and cleanest option. The word biofuel describes an energy source obtained from a biological process, such as anaerobic respiration or photosynthesis”.
He stopped for a brief second, as he stuttered the word photosynthesis.
“Currently, the most common biofuel is ethanol, produced from crops such as corn or sugar cane. But how much farmland would we need to
attend our fuel demand? Isn’t food production a more pressing matter? How can we efficiently make clean biofuels without relying on plants?”
He waited for a response, even though he knew his questions were completely rhetoric.
“With that in mind, I have decided to find an answer in the microbial universe. As all of you can imagine, a microorganism grows quickly
and requires less space and energy to survive. Microalgae caught my attention right away, given how biologically similar they are to the plants already used as a source of bioethanol or oil. Out of the many interesting microalgae, I chose Chlorella protothecoides as my
model organism. This species can grow surprisingly quick, maturing in a little over 24 hours”. (1)
He caught himself getting excited.
“Even though they are invisible to the naked eye, the amount of oil that this alga produce is almost thirty times larger than that of
conventional crops! In one cubic meter I can produce about 1,7 kilograms of Chlorella in a day, a biomass that is over 50% oil (1). This oil is biodegradable and nontoxic, and can be converted into a biodiesel, potentially fueling cars and generators.”
He took a few seconds to recollect himself. He took a sip of water and continued.
“Much of my recent research consisted in the optimization of oil production by Chlorella in heterotrophic conditions, which involves
feeding the algae with some organic molecules. I found that by altering pressure and temperature, ranging from 150 to 300 bar and 35 to 70 degrees Celsius, the amount of oil produced changes drastically. At my limit conditions, supercritical oil extraction was as high as 21 grams per kilogram of algae!” (2)
He quickly flipped through his notes, making sure he did not get confused with the numbers.
“My studies also show that the extreme conditions help with oil extraction, and I believe this process can be further optimized to increase biomass productivity to extract amounts of oil nearing the 50% volume produced by each cell.” (3)
He pointed to the one of the chairs in the corner of the room and continued to geek out.
“That means that right now, in the roughly 1 cubic meter space that that chair occupies, I can produce 35.7 grams of oil in one day under the conditions I’ve determined. The oil is esterified producing FAME, or fatty acid methyl ester, the main component of biodiesel. My experiments showed that potassium hydroxide can act as a catalyst, enhancing esterification in a reaction that yields 98% FAME under the right conditions.” (4)
He stopped himself from sharing these conditions - 0.5% catalyst, at 60°C for one hour, with a methanol to oil ratio of 8:1 – out of fear he would be sharing too much. He continued.
“Assuming that one kilogram of your average biodiesel from crops produces 37.1 megajoules of energy, I would need a little over 100 cubic meters of Chlorella to produce the same amount of energy as one gallon of biodiesel! (5)
He could hear the whispering from across the room. One of his viewers then asked “How do you envision this succeeding? What real life
applications do you see here?”
Without hesitation, he answered: “I believe micro algae can revolutionize the production of biodiesel! The space and resources needed
to maintain the algae stocks are significantly less than what is needed for crops. One acre of corn, for instance, generates about 18 gallons of oil after 3 months of growth. This amount of oil could be made in a single day in about 1700 cubic meters of algae! That is about half of an Olympic size swimming pool, which occupies only one fourth of an acre.” (6)
He was prepared to keep talking, but was interrupted by another viewer: “Very good Dr. Green, thank you for your presentation. Would you like to make any final remarks?”
He concluded: “Thank you once again for giving me the time. I hope you can see the potential algal biofuel have as a substitute for
fossil fuels. Although I still have more optimization to do, I believe this project already has the potential to be economic and environmentally positive. I am ready to explore this idea in an industrial scale, forever changing the production of biofuel! I look forward to hearing your remarks and feedback”.
That last sentence came out shaky – he was prepared to leave the room without looking back. To his surprise, they burst into applause.
He felt a warm tingly sensation in his stomach – he had done it!
After a series of handshakes, he left the building and walked down the street, feeling his day a little brighter and much greener.
Note: This is a fictional short story – the scientific work
was conducted by different research groups, cited below.
1. “Microalgae Oil” –
Soley Institute (http://www.soleybio.com/oil-trade.html)
2. Viguera, M., Marti,
A., Masca, F., Prieto, C., Calvo, L. (2016). “The process parameters
and solid conditions that affect the supercritical CO2 extraction of
the lipids produced by microalgae”. The
Journal of Supercritical Fluids. 113:16-22.
3. Berteotti, S., Ballottari, M., Bassi, R. (2016).
“Increased biomass productivity in green algae by tuning non-photochemical
quenching”. Scientific Reports. 6:21339.
4. Kumar, M, Sharma, M. P. (2016). “Kinetics of
transesterification of Chlorella Protothecoides microalgal oil to biodiesel”. Waste and Biomass Valorization. 7(5):1123-1130.
5. “Fatty Acid Methyl Esters (FAME)” – European Biofuels (http://www.biofuelstp.eu/factsheets/fame-fact-sheet.pdf)
6. “Oil yields and characteristics” – (http://journeytoforever.org/biodiesel_yield.html)
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