Oil is Green with Envy
It’s self evident that our world demands a scalable renewable energy source to replace fossil fuels as current energy prices continue to rise each year. There are thousands of different ideas, strategies, and interventions for alternative energy, biofuels seem like a clear solution. For any new energy source to be a long-term replacement for current energy systems, it must satisfy three major demands. (1) Infrastructure demands. Any new energy source must be able to meet global demands, while keeping the cost of implementation from exceeding the benefits. (2) Political demands. Not only is government money funding the research required to turn innovation into reality, but also if a new solution is not easily regulated any wide scale implementation will likely be thrown out. (3) Economic demands. Current energy providers must be able to continue to profit for any solution to be adopted wide scale, or attempts of inventors will be thwarted. Based on these three critical factors, there is one solution that fits the criteria: biofuels.
Biofuels are the most likely new energy source to win the race to a universally accepted replacement for crude oil, for very simple reasons. A biofuel solution requires little or no change in the majority of our systems, we would still put gas in our cars, oil companies could still sell fuel, and governments would still collect taxes. More importantly it is also the solution that has the greatest scientific chance of satisfying the growing energy demands.
Biofuels are fuels derived or created from biomass that come from a renewable source, commonly corn and soybeans. To replace our current fuel system with corn, it would require 800% of the United States arable land. By looking at the numbers this is simply impossible.
“If all the soybeans grown and harvested in the U.S. each year were converted into biodiesel, the resultant fuels supply would accommodate less than 10% of our annual diesel fuel consumption. Conversely, if an area roughly equating 1/10th the land area of Utah were developed into algal energy systems, algae could supply all of America’s diesel fuel needs” (Muhs et al., 13).
Algae have the potential to augment the world’s fuel supply as well as reducing greenhouse gasses. “Algae yield greater volumes of biofuel per acre of production than crop plant-based biofuel sources. Algae could yield more than 2000 gallons of fuel per acre of production per year” (“Exxon Mobil” 1). Conversely, corn produces 250 gallons per acre per year, and soybeans produce 50 gallons per acre per year. It is clear that algae are far more efficient due to their highly productive nature.
Turning Algae into Biofuel in Five Steps
There are 5 basic steps: (1) Gathering the raw materials. (2) Mixing and Growing Algae, (3) Harvesting and Drying, (4) Oil Extraction and Product Generation, and (5) Refinement of Bio Oil into useable Fuel. An extraordinary aspect of algae is its ability to grow in many different situations. “Algae can be grown using land and water unsuitable for crop, plant, or food production” (“Exxon Mobil” 1). Since photosynthesis is used in the creation of algae oil the required elements are: algae, water, carbon dioxide, sunlight, nutrients, and land. In the Unites States, sunlight is the most continual in the southwest region. Because land is not an issue it could be grown anywhere, including a desert. The next important piece is water. Researchers are looking at all options including: salt water, fresh water, and even wastewater. Wastewater would provide both a medium to grow in as well as nutrients. The end result would be clean water, oxygen, and algae biomass.
Picking the right kind of algae is very important to yield the highest biomass, which creates the most fuel. Today, with the help of biological and genetic engineering, scientists can take standard algae organisms and engineer them to fit their needs. The ideal algae organism needs to be “[a] robust organisms that grow and accumulate lipids rapidly under diverse environmental conditions” (Muhs et al., 17).
“As [algae] grow, [they] accumulate fats and bio-oils that has similar molecular structures to traditional crude oil” (“Exxon Mobil” 4). Algae can be grown in either open ponds, or enclosed reactors. Each method has its pros and cons. Open ponds closely relate to algae’s natural environment and are inexpensive to build and operate. “However, these ponds provide significant drawbacks including: low algae production on surface areas, inability to strictly control the algae environment, water evaporation, low volumetric cell densities, and the risk of contamination by predator strains” (Muhs et al., 18). “Photobioreactors possess a lower risk of contamination, [allowing] better control and regulate nearly all of the important process parameters” (18). They reduce the risk of losing CO2 or water to evaporation and have a higher reproduction rate. In turn, this generates “greater productivity (which reduces land requirement), and reduced harvesting costs (due to the higher cell densities achieved). Conversely, the capital and operating costs associated with photobioreactor-based cultivation systems are significantly greater than open ponds” (18). Without sufficient research, Without sufficient research, nano conclusive evidence has been found to be better than the other.
Following the growth of algae, the algae have to be separated from their culture medium to isolate the oil in the algae cells. Currently, there are three main methods for this process. The first is filtration, where the liquid is pushed through a filter using a vacuum to pull the water through. Although the method is simple, the major drawback includes intensive labor to keep the filter from getting clogged. The second option includes “a continuous or semicontinuous process; it appears to be more efficient. However, it is energy intensive and cannot readily be scaled for large applications, called centrifuging” (22). The third option is called flotation. This process occurs when air bubbles are pushed through the water to the surface creating an algae froth, which can then be skimmed from the water. This process is challenging for two reasons, (1) Algae is very small and, (2) Algae comes in a low concentration for which it can be grown (typically 3–20 microns).
There are three main ways for extracting the oil from algae cells, (1) expeller/press (2) solvent extraction (3) supercritical fluid extraction. The expeller/press method is simple, but requires dried algae and recovers 70–75% of oil. Solvent extraction recovers more than 95% but is more complex as it uses co-solvents to open the cells and release oil. Supercritical fluid extraction uses CO2 to extract oil but requires high-pressure equipment. Just like normal crude oil, algae oil has similar structure, which results in many simplified benefits. Because of the similarities “Bio-oil will be further processed in existing refineries, just as crude oil is refined today, to produce a range of products including gasoline, diesel, jet and marine fuel” (“Exxon Mobil” 4). Once processed, it can be used just as normal fuel is today with very few changes to typical combustion engines. This cuts down on costs of creating renewable energy as the technology grows and is scaled to support our nation.
Biofuels provide our nation with better energy products, and growing algae can consume carbon dioxide; providing greenhouse gas mitigation benefits, allowing us to live in a cleaner environment. With biofuels, accidental oil spills will become a piece of history as they have the ability to dissolve back into our environment. Algae’s amazing properties along with today’s leading research and development give it one of the best shots at replacing our dependency on oil.
“Algae Biofuels Research and Development Program.” Exxon Mobil 1.1 (2010): 1–4. Web. 8 Nov 2011. <http://www.exxonmobil.com/corporate/files/news_pub_algae_factsheet.pdf>
American Chemical Society. “‘First Economical Process’ For Making Biodiesel Fuel From Algae.” Science Daily 31 March 2009. 7 November 2011 <http://www.sciencedaily.com/releases/2009/03/090325222006.htm >
Master, Nation. “Energy Statistics.” NationMaster.com. CIA World Factbooks, 18DEC2008. Web. 2 Nov 2011. <http://www.nationmaster.com/red/pie/ene_oil_con-energy-oil-consumption>.
Muhs, Jeff et al. “Algae Biofuels & Carbon Recycling.” USU Energy Center 1.1 (2009): 4–27. Web. 7 Nov 2011. <http://biofuels.usu.edu/htm/downloads/publications>.
West, Larry. “The Pros and Cons of Biofuels.” about.com, Environmental Issues. About.com, 5 Nov 2011. Web. 30 Nov 2010. <http://environment.about.com/od/fossilfuels/a/biofuels
Christenson, Logan. ALGAL BIOFILM PRODUCTION AND HARVESTING SYSTEM FOR WASTEWATER TREATMENT WITH BIOFUELS BY-PRODUCTS. Diss. Utah State University, 2011. Ann Arbor: UMI, 2011. Print.