MAR 12, 2019

Algae Biofuel--What Happened After the Hype?

WRITTEN BY: Daniel Duan

During the first decade of the 21st century, the world saw a rapid surge of research and development activities surrounding algae biofuel. The concept, which combines biological carbon capture and accelerated fossil fuel creation in its essence, has the environment-friendly appears.and advantages over the production of fossil fuel and energy source from other types of biomass.

After dozens of organizations spending hundreds of millions of dollars-worth investment, a significant portion of which came from Exxon Mobile and the Department of Energy, the bubble burst as no one managed to achieve a commercial scale process. The idea of extracting fuel oil from algae was since considered neither commercially viable nor environmentally responsible.

The boom started when algae were discovered to be much more efficient in capturing carbon and turn them into biofuel, as compared to terrestrial plants such as palms and corns. Algae do not require good quality land, so using algae as a source for biodiesel can alleviate the competition with food crops.

The genetically diverse, lipid-rich watery plant is not picky about water either: wastewater from farming, contaminated with fertilizers can be used as its primary source of water and nutrients.

Since many algae species are excellent bio-fixers, meaning the production process of algae biofuel can be a carbon-negative process, even though about a good percentage of the carbon will be released back to the atmosphere during fuel consumption. But the byproducts and scrap from algae can be easily buried as composting.

Later on, as more R&D was carried out, it turns out that growing algae in the industrial scale would require about the same footage of land if not ocean as other traditional fuel crops. It was calculated that an algae pond would need to suck around 4g of carbon from the atmosphere and transformed that into biomass per square meter (or 11 square feet) every day, in order to sustain fuel production and extraction.

From the biochemistry point of view, the amount of fertilizer that the growth of algae would need in an industrial setting is also astounding and may result in unhealthy competition with the need for food crop farming.

Some of the biofuel startups survived the burst, but they all switched gears to focus turning algae into other high-value products such as cooking oil, dietary supplement, and food coloring products. Meanwhile, algae biofuels research and development is still alive, with a smaller amount of funding dedicated to plausibly breakthroughs, in both biology and engineering.

For instance, chemical engineers from the University of Utah reported a new, energy-efficient method to extract lipids from the watery plant: they developed a new mixing reactor in which jets of the extraction solvent run against jets of algae, creating turbulence that "suck out" liquid from algae with ease.

As many are hopeful that more innovation will put us closer to turning algae into a viable, cost-effective alternative fuel, it is important to bear in mind that any breakthrough in industrial technology takes time, money, and careful, lengthy R&D.
 

Energy 101 | Algae-to-Fuels (DOE)

Source: Forbes