Ms. Zoey Perrine is a graduate student at OSU and she spoke to us on her research on strategies for improving light utilization and productivity of microalgal cultures. Algae serve as an attractive biofuel feedstock; it is microscopic and contains photosynthetic organisms that live in saline or freshwater environments. Algae have 20-50% non polar lipids and superior solar energy conversion efficiencies. According to Ms. Perrine, algae are 6-12 folds higher in energy yield and have a very fast growth rate (doubles in 6-12 hours). When algae are used as a biofuel feedstock biomass is harvested 100% of the time and it is harvest everyday, all day. Microalgae have greatly decreased land area requirements than other plant based biodiesel feedstocks and have higher biodiesel productivity per year than other feedstocks such as corn maze, soybean and palm oil.
Before going into her research, Ms. Perrine discussed the factors that are affecting the cost of producing biofuels from algae. One major focus is that the use of algae enhances photosynthetic efficiency and it grows well across a wide range of temperature and light. There are two steps to increase light utilization by microalgae. One, photosynthetic active radiation must increase and two, we need to eliminate or decrease light harvesting antenna complexes. The second step reduces the light absorption cross sections of algal cells and prevents chlorophyll b to be synthesized from chlorophyll a.
She also found that the photosynthetic capacity increased with the use of algae as a feedstock for biofuels. This increase affected the growth rate of the algae; they found that algae with intermediate antenna size performed as well as the wild type under low light conditions and increased culture productivities at moderate high light intensities. Algae with large antenna are less efficient at high light intensities because they lose energy through real fluorescence. She also found that increasing pond depth allows for greater culture productivity in algae with small antenna.
Overall, Ms. Perrine’s research found that the growing and culturing of algae for biofuel production can account for 50% of the cost of biofuel production and increasing the photosynthetic productivity of microalgae cultures will drive down costs of production. Also, a deeper pond depth will increase productivity. Her discussion of her research was extremely beneficial to furthering my understanding of algae as a potential feedstock for biofuels.
After the previous lecture it was really interesting to transition into a lecture from a company who developed a method for producing biofuel from algae. D. Craig Smith is the COO of Algenol Biofuels Inc. He talked to us about a novel and cost effective method for producing ethanol from carbon dioxide in hybrid algae. His research was based on concepts that are directly related to ethanol. His company is a private industry and is globally operated. The new technology that they developed produces ethanol from carbon dioxide using hybrid algae. Hybrid algae are grown in seawater contained in proprietary, enclosed photobioreactors. They grow the organisms in an enclosed photobioreactor because this prevents ethanol from being released into the environment. Their company has developed a flexible plastic bag into which they put seawater and algae together and when the sun heats up the bioreactor ethanol is produced and escapes into a vapor phase. When the temperature drops the heat is transferred across the surface of the plastic. He explained that this is why it was important to use plastic because plastic has the characteristic of transferring heat and producing condensation. The water condensate forms and is collected in ethanol seawater and ran through a processor. It then goes through a final distillation and dehydration process and ethanol is produced.
The company is very close to creating a large scale facility, but currently produces the ethanol in small scale facilities. Compared to other conventional methods, this process does not use a lot of freshwater, which is extremely beneficial. The company hopes to produce 6,000-10,000 ga/acre/yr of ethanol. They say they are very close to being able to do this. Also, they are able to keep their capital costs to under $5/ ga capacity and their operating costs less than $1.00/ga/yr.
Dr. Smith listed the companies 2009 accomplishments, all of which were extremely significant to the production of biofuel from algae. Overall, their company has developed a technology that uses carbon dioxide as the feedstock to make ethanol and organic chemicals in hybrid algae. Photosynthesis converts the light into chemical energy and no food is used as feedstock. Also, their biorefineries are built on desert or marginal land; therefore they are not using land that can be used for other things. Finally, their technology uses seawater and cheaper nutrients and it is a cost effective method for producing very large volumes of biofuels.
I thought these two lectures went really well together because I first learned about why algae is a beneficial feedstock for biofuels and then learned about a company who recognizes the benefits and sought out a way to actually produce biofuel from algae at a large scale.
Dr. Charles Wayne spoke about the biomass refinery that is currently being researched at Consortium for Applied Fundamentals and Innovations (CAFI). CAFI’s mission is to help companies select technologies for application when it comes to biomass refinery. They say it is important to not downselect pretreatments because it is vital to the process, but we must just find pretreatments that work. The talk focused mainly on applications they found for corn stover, poplar wood and switchgrass. Corn stover, according to Dr. Wayne, is one of the easiest biomass to convert into biofuel. They looked at the effect of various methods of pretreatment, such as, AFEX, dilute acid, lime and liquid water on each type of biomass. They found the effect of cellulose loadings and beta-glucosidase supplementation on release of glucose and xylose; they found no effect. Dr. Wayne discussed CAFI’s findings on many other issues such as changes in sugar release when other enzymes are introduced and the similarities and differences in sugar release from pretreatment and enzymatic hydrolysis of the different biomass. He also discussed the effects of pretreatment of the biomass on the cost; he says that even though pretreatment is a significant part of the process, it is only part of the total capital and operating costs. He also says that high yields are critical to low costs, which I interpreted this as a need for low operating costs and high yields to be able to stay/be competitive. Overall, the key messages he wanted to demonstrate were that transparent material balances should be a standard requirement for all applied biomass. Also, it is important to understand that pretreatment is still required because yields are low without it. However, the choice of pretreatment will depend on interactions with the rest of the process because not all pretreatments were equally effective on all feedstocks. Overall, this talk was extremely interesting, but I had a really hard time understanding everything he was talking about. Importantly though, I do believe I understand the basics about biomass refinery and that pretreatment, even though it is more costly, it is still needed because of the high yields pretreatment gives.
One of my favorite talks that I listen to was about emerging standards and policy for biofuels. Dr. Ogorzalek works for the World Wildlife Fund and he spoke about how biofuels is important to our solution to decreasing global materiality. He discussed the current use of the earth’s natural resources and what our life and environment will be like before the next century. Since we are on a track towards overpopulation and resources running out we need to learn how to do more with less because we will be forced to and biofuels will help us to do achieve this. He presented a list of policies and standards are being developed and put in place that will allow us to introduce and use biofuels in as sustainable manner as possible. Such standards that he discussed were Better Sugarcane Initiative (BSI), Council on Sustainable Biomass Production (CSBP), Global Bioenergy Partnership (GBEP), Green Gold Label 2: Agriculture Source Criteria (GGLS2), International Sustainability & Carbon Certification (ISCC), Roundtable on Responsible Soy (RTRS), Roundtable on Sustainable Biofuels (RSB), and Roundtable on Sustainable Palm Oil (RSPO). According to Dr. Ogorzalek, all of these standards obey the law, have high conservation value, have areas that are not to be converted to feedstock production, they maintain or improve soil quality and they protect and improve freshwater resources all of which they do in a variety of ways. However, only BSI, ISCC and RSB are RED compliant for greenhouse gas savings, BSI is the only standard that is metric based and they do not all deal with indirect land use change. Also, only BSI and ISCC require environmental and social impact assessments and only BSI, ISCC and RSB look into improving air quality from production. Overall, the main goal is to freeze our footprint by tripling food production with the same amount of food we are using now, by 2050. According to Dr. Ogorzalek, we can achieve this goal by using genetics, improving poor management production and bringing land back into consumption. I thoroughly enjoyed this talk the most because I could understand it and it was extremely interesting to me. With my major and my focus in graduate school, I will be looking into learning more about this type of situation and researching and presenting solutions so listening to a talk that I could picture myself giving one day was very exciting.
Mr. Sam Jackson works for Genera Energy in Knoxville, Tennessee. Genera Energy partnered up with The University of Tennessee Biofuels Initiative (UTBI) to create a farm-to-fuel business plan. He discussed the state of Tennessee’s perspective and initiatives for biofuel production. The UTBI works with local farmers to develop switchgrass production. Switchgrass is a feedstock for biofuel; it is a native warm season perennial grass, it tolerates a wide variety of conditions- wet or dry, poor soil, works similar to hay production and it takes 3 growing seasons before reaching full maturity. In order to successfully produce a high yield of biofuel one has to have an insurance of feedstock, an adequate and consistent supply of feedstock and have to allow the farmers to make a profit and it has to be economical for the consumers. Since Tennessee understands all of these requirements, they have been able to establish a $70.5 million statewide commitment, which includes two steps: one, establishing an energy crop supply chain where they work with farmers who grow 6000+ acres of switchgrass and then that feedstock is used to make biofuel. Currently, Genera Energy is using corn as their feedstock but they are very close to being able to switch over to switchgrass. The company created a first of its kind production program for switchgrass where they work with farmers through contracts and have incentive programs for the farmers. The farmers are invited to informational meetings where they go to switchgrass production seminars. They also receive application packets and the selected farmers receive a 3 year contract to plant and produce switchgrass. Genera Energy pays the farmers $450 per acre per year for costs of production and opportunity costs and UT provides Alamo switchgrass seed and technical expertise. According to Mr. Jackson, the majority of their switchgrass is just entering their 3 year of maturity; therefore, they will have a lot more data after this year. Mr. Jackson discussed some issues that go along with using switchgrass as a feedstock such as, seed crop availability and the cost of the crop increasing. This was mostly due to President Bush mentioning switchgrass in one of his State of the Union’s during his presidency; as soon as he mentioned it the cost increased. Some other issues include equipment and herbicide availability and figuring out what herbicide goes well with switchgrass. Also, currently they use round bales of switchgrass and this is not efficient in regards to transportation. Overall, Mr. Jackson says that until we have a sustainable biomass supply, we won’t have a consistent use of biofuels. Therefore, research and development is still needed and Tennessee is one of the key contributors to moving this process forward.
Throughout the week I enjoyed listening to the various topics on Biofuels. I was able to pick out areas that we complicating and areas that I was very interested in learning more about. I especially liked learning about the actual process of refining biofuels from the different feedstocks and then learning about different companies approach to doing so. Overall, I thought the trip was extremely beneficial and educational and it could have not been in a more perfect location!