The following is a response to the article Could Algae be the New Corn? by Julia Verdi. She raised the following questions... Does Algae pose the same risks as corn? Are biofuels the wrong way to go when it comes to identifying fuel sources?
Great article Julia! I did a study on algal biodiesel for one of my graduate classes and wanted to add some notable points.
1) Algal biodiesel is considered to be a third-generation biofuels, meaning that it does not come from a feedstock used for human dietary consumption, and has a very low land and water input requirements. This is why algae are superior to plant-based feedstocks like soybeans, corn, switchgrass. Algal production, or algaculture, has a smaller environmental footprint with regard to land use as it avoids large-scale deforestation, and the inherit problems associated with the continual increase of arable land. Algaculture also avoids problems inherit with modern farming techniques. Today agriculture has become and “industrialized” process. In the United States, the number of farms has decreased, and productivity of each individual farm has increased. However, this increased productivity has come at a cost. Agricultural practices now rely heavily on the use of harmful chemicals as fertilizers and pesticides to optimize growing conditions for crops, including poor irrigation techniques and chemical fertilizers.
2) Energy density is important, but let’s talk about sheer bio oil productivity numbers. Algal biodiesel is favored over other biofuels made from plant-based feedstocks because algae are very simple organisms when compared to plant-based feedstocks, and do not produce excess tissue such as stems, leaves, or roots. They receive all the physical support they require from their surrounding aquatic environment. This means that a larger percentage of algae’s biological processes are devote to production of natural oils, resulting in a higher oil yield. Studies have shown that production of bio oils for corn is around 145 kg/hectare/year, while Spirulina microalgae and diatom algae can produce up to 18,000 and 43,200 kg/hectare/year, respectively. Those numbers are staggering!
3) Algal biodiesel is a decarbonized liquid fuel which will allow for an easy transition into the existing infrastructure of pipelines and filling stations originally devoted to petroleum-derived fuels. According to 2002 Census data, 121,446 filling stations are present in the United States. Of which, approximately 35% – 40% currently sell petroleum diesel fuel. This means that the United States has a sophisticated liquid fuel distribution system, and algal biodiesel should be quite capable of operating within its bounds.
You might be asking yourself, “How can we put algal biodiesel into the engines of our trucks and buses? Won’t this be a problem?” The answer is NO. As a matter of historical interest, Rudolph Diesel first used peanut oil at the turn of the 20th century to demonstrate his patented diesel engine. This means that the diesel engine was originally designed to run on biodiesel, and petroleum diesel fuel came into the picture much later. Algal biodiesel is a quality fuel that can be used in existing diesel engines with a slight retrofit modification. This retrofit can easily be installed and does not diminish the performance or the lifespan of the engine. However, there have been problems with engine manufacturers not honoring warranties on engines with biodiesel retrofits. This is primarily due to the reluctance of diesel engine manufactures to accept after-market technology improvements. This basically comes down to a legality issue and how it is easier for companies to deny a warranty claim on a modified engine to save some money in the short run. It is anticipated that as biodiesel retrofits become more widespread within the transportation industry, engine manufacturers will modify their warranties to accommodate biodiesel retrofits.
4) Algal biodiesel is a promising carbon mitigative solution, although it is not perfect. There are some risks and limitations that need to be addressed before commercial production can occur. One of the biggest problems with algal biodiesel is the high costs for implementing the technology. David H Kurzman of Kurzman Cleantech L.P. said that as of 2009, “there is not yet a commercially viable algae approach”. Luckily, there are no shortages of investors throughout the world who are looking to gain profits from companies working on developing a low cost business model that can scale up production to commercial levels.
Finding ways to reduce costs associated with every aspect of algal biodiesel production is essential. There are fixed costs from the project’s inception starting with the construction of ponds, as well as the ongoing operational costs of culturing the algae species, providing nutrient and energy inputs, isolating the bio oil, and the conversion to a usable liquid fuel. There are other ways to reduce overall costs by selling “waste” products of the Companies also hope to squeeze capital gains out of the process by turning the biomass remaining into animal feed or ethanol. In order for algal biodiesel to have success in the future, it is important that the costs are reduced so that it is able to compete in an open market with similar liquid fuels.
5) Another limitation that will need to be overcome before algal biodiesel can be considered a successful commercial technology is identifying a steady and reliable source of carbon dioxide. Every 1 unit of algal biomass produced requires twice that amount in carbon dioxide in order to sustain commercially viable productivity levels. Ambient absorption of atmospheric carbon dioxide would not be sufficient to sustain commercially viable algal production, despite concerns about its increased concentration over the past couple of hundred years (i.e., greenhouse gas effect). This means that concentrated sources of carbon dioxide must be delivered to the algae diesel production site from fixed and mobile vehicle point sources. One source could be captured carbon dioxide emissions from the stacks of coal-fired power plants. Coal-fired power plants are obviously major sources of carbon dioxide, but how can you capture it efficiently and cost-effectively? Again, companies are working on low-cost solutions, but a perfect solution has yet to be discovered.
6) There are also reservations regarding the control, or lack thereof, of factors related to production of algal biodiesel. Weather changes, exposure to biological agents in the atmosphere and solar irradiation have the potential to significantly disrupt production. These often unforeseen factors are difficult to plan for when operating an algal bio oil production facility. Climatic conditions also play an important role when determining the best locations for algal production sites. Sunny and warm growing conditions are achieved in desert areas during the daytime are optimal for algal growth and bio oil production, however, the abrupt drop in temperatures at night are prohibitive to sustaining the best growth rates.
Overall, I think that we should not give up on algae as a source for liquid fuels. The technology isn’t perfect, but luckily there are brilliant minds dedicated to solving the problem. Petroleum has enough inherent problems and its days at the top are numbered. Algal biodiesel could be the wave of the future.
© 2010, Frank Ciampa. All rights reserved. Do not republish.