Algae can be used to generate clean electricity, as it uses CO2 in the atmosphere and light from the sun during photosynthesis to create essential macromolecules, including lipids. These lipids, when isolated as oil, can be burned and used as fuel to generate energy. 

As discussed in the previous Synopsis, global warming occurs when massive amounts of net carbon dioxide enter the atmosphere, reflecting heat back onto the surface of the Earth, and the burning of fossil fuels accelerates that warming by an alarming rate. This is why biofuel is such a promising alternative; it is carbon neutral because the same amount of CO2 released into the atmosphere had already been absorbed in photosynthesis.

Algae is a perfect candidate for biofuel because it grows at rapid rates: some species can double in just two hours. Algae was a huge contributor in the azolla event, a period millions of years ago when 80% of atmospheric CO2 was absorbed by azolla and symbiotic algae, cooling the Earth to a remarkable extent. Additionally, algae can be grown just about anywhere, even seawater, where other biofuel sources require very particular circumstances.

Soybeans and canola are current main sources of biofuel, but they require a lot of fertile land that could be used to grow other crops. In order to replace all petroleum-based transportation fuel in the US alone, soybeans and canola would respectively take up between one and almost three billion acres of fertile land, of which the US only has 434 million. However, algae would only require 95 million acres of land, none of which need to be fertile soil.

Despite the host of attributes that make algae an ideal source of energy, it won’t be achieved easily. Algae grow so fast that it blocks essential light, so growth rates must be limited with computer systems that control the nutrients that are added to the tank. Additionally, in order to acquire the high lipid content desired when producing fuel, algae must be convinced that it needs to store fat. However, this can slow its growth and put its health at risk, so it must be harvested right when it has the most stored fat but hasn’t yet declined from the stress.

Funding for algae biofuel is a huge hurdle blocking its success, as it relies on whether fossil fuels are expensive enough for businesses to seek an alternative, and progress takes time. The Aquatic Species Program (ASP) was founded in 1978, and studied algae biofuel, but was disbanded in 1996 when the researchers had failed to extract significant amount of oil. They attempted to grow a type of algae that produced a relatively high concentration of lipids, but their ponds would be overtaken by wild algae.

Although the project was unsuccessful in its mission before it was dissolved, it was on the right track in terms of pursuing a variety with a high fat content. Gene editing tool CRISPR has increased genetic efficiency in how algae can use sunlight and handle growing conditions, opening the door to new species of algae that produce more lipids and can endure more adverse conditions.

Extracting the lipids from algae is no simple task: most plants’ fat is extracted through cold pressing, but algae isn’t fibrous enough for it. Adding methanol or hexane is an efficient and affordable way to extract oil, but potential environmental impact prevent them from being used without further research. Isolating the oil is possible, but is difficult to achieve at a price competitive with fossil fuel.

Despite the array of challenges facing algae innovation in the world of biofuel, it has incredible potential and has already been implemented commercially. Since plastics are made from fossil fuels, it can be made from algae. A company called Algix worked on harnessing that very power, and converted millions of pounds of algae into shoe soles. Additionally, algae biofuel was already powering military vehicles and UPS trucks by 2012 in demonstration projects.

Although the battle for prevalence in a world so dependent on fossil fuels will be tough, algae has fantastic and undeniable implications for the future of sustainability. With time and proper funding, algae has the capability to revolutionize clean energy.

This paper was long but so informative! I actually had no idea that algae could be used as an energy source, and a great one at that. This took me a significant amount of time to put together, but I’m really glad I did! I was actually going to post this last week, but as I started to assemble it from my research, I realized that the background knowledge required about CO2 should be in a post of its own. I’m glad I chose to separate the topics instead of combining them to one post, because this one is long enough as it is.

Hearing about all of the promise algae holds for the future of energy is exciting, but knowing its hardships in the past with the ASP is concerning. Hopefully innovations will be made and we will see more algae implementation in commercial settings in the near future.

Svoboda, Elizabeth. “Algae Is a Good Source for Biodiesel.” Biofuels, edited by Margaret Haerens, Greenhaven Press, 2012. At Issue. Gale In Context: Opposing Viewpoints, link.gale.com/apps/doc/EJ3010817214/OVIC?u=ante588&sid=bookmark-OVIC&xid=1e35e738. Accessed 3 Apr. 2023. Originally published as “The Greenest Green Fuel,” Popular Science, 7 Jan. 2007.

Kassinger, Ruth. “How Slime Will Save the World.” Boston Globe, 07/28 2019. ProQuest; SIRS Issues Researcher, https://explore.proquest.com/sirsissuesresearcher/document/2302779565?accountid=163174.