Sustainable Growing of Algae in High Tunnels for BioFuels
The project, initiated in 2008 during a critical time in the economy when oil had reached the highest ever price of $140/barrel, and continued successfully during its second year in 2009.
In the meanwhile farmers found temporary relief from the high cost of fuel for equipment and transportation but it was not long before prices started to creep up again. And since fossil fuels are a limited resource, which has already peaked out, in the long term things can only get worse. The anxiety among the major oil consumer companies in aviation and land transportation, including the Military is growing exponentially as the 2012 deadline for introducing the carbon cap and trade closes on the time left to develop alternative renewable fuels.
The corn to ethanol companies, which were facing bankruptcy during the period of oil price drop below $1.50/ gallon emerged from this critical position and benefited from the oil price increases above $1.60/gallon. Now corn ethanol is the dominant alternative fuel, backed up with substantial subsidies despite that it proved to be a wrong and unsustainable approach for renewable biofuels. While we burned 30% of the corn, produced last year in the US, as ethanol, we continued to contribute to the high food prices and the hunger in many countries of the world.
Although the need for alternative renewable sources of biomass for fuels has never been so important, it is neither justifiable, nor sustainable, to grow our fuel using the most fertile land that corn requires.
Growing micro-algae for bi-fuel does not compete for land with agricultural crops and can produce much higher yields per acre per year.
During the second year of the project our team focused on optimizing the conditions for growing the algae in Missouri. Several species of algae, from the ones collected locally were selected for a scale up growing, both outside and inside a High Tunnel. While all tests outside were limited in late fall by the dropping night temperatures and lower growth rate, the algae grown inside the High Tunnel equipped with a Geo-Solar system continued successfully through yet another, even colder winter. The lowest temperatures this winter reached a 10-year record of –10 degrees F and a windchill of –30 degrees F. Under these challenging conditions we were able to test and further extend the capabilities of the High Tunnel with a Geo-Solar system to grow algae at such extreme winter conditions. This is a very important step in our plans to demonstrate that it will be possible to grow the micro-algae further north in Iowa, where there are even bigger temperature challenges.
The goal to extend the growing season beyond the climate limitations for growing outside in open pond or closed type systems was successfully achieved by growing inside the High Tunnel equipped with a Geo-Solar system, utilizing the energy harvesting and energy storage capabilities of the designed system.
We performed numerous experiments to establish the effect of the various parameters like temperature, light exposure, nutrients and their concentration, flow rate, turbulence and pH of the growth media, by measuring the density of the algae in the culture media to determine the optimal conditions for the highest algae biomass production. The results were used to scale up the aquaculture volumes and harvest the algae biomass that was then processed to extract the oil for bio-diesel, the carbohydrates for ethanol and the protein for feedstock or nutritional value-added products.
We have developed a new technology including a very efficient, quantitative extraction of algae oil by Supercritical Fluid Extraction. While current procedures for oil extraction require the use of the toxic and flammable solvents like hexane or cyclohexane, the Supercritical Fluid Extraction eliminates the use of above hazardous solvents, using only carbon dioxide for the extraction. Another advantage is the mild conditions for the extraction and the possibility to carry out a continuous countercurrent oil extraction process. This technology however required equipment which was not readily available for our project. It also required additional training and experience but its application improves tremendously all currently known methods for oil extraction. We are working in close collaboration with MOR Technology Inc. (www.mortechnology.com), the developer of the Continuous Countercurrent Supercritical Fluid Extraction equipment.
Our common goals and joint efforts have resulted in an application for a grant with the Iowa Power Fund for $ 2.1 million. It has been already reviewed and recommended for funding by the Midwest Research Institute (MRI), which is an official consultant of the Algae for Biofuel Research by the National Renewable Energy Laboratory (NREL) at the Department of Energy. MOR technology is in the process of merging with a big ethanol company, which will become the backer for the commercialization phase of the project, but the legal processing has taken a longer time than expected.
Up to this stage the Grant money was used for equipment, materials and supplies, scale up photo-bioreactors and compensation of the project participant farmers.
The key result was the demonstration of the possibility to grow algae in Missouri in a High Tunnel equipped with a Geo-Solar system, coupled with a used oil furnace, in the middle of the winter. The lowest temperatures this winter reached a 10-year record low of –10 degrees F and a windchill of –30 degrees F. Under these challenging conditions we were able to test and further extend the capabilities of the High Tunnel with a Geo-Solar system to grow algae at such extreme winter conditions. This is a very important step in our plans to demonstrate that it will be possible to grow the micro-algae further north in Iowa, where there are even bigger temperature challenges.
A selection of algae strains was produced as a result of extensive cultivation experiments under various growing conditions.
A new technology was developed for the complex utilization of every component of the algae biomass using Supercritical Fluid Extraction of the algae oil.
An in-depth cost analysis was performed to support the efficiency and profitability of our approach to grow algae by complete simultaneous utilization of the oils for biofuel, the cellulose for ethanol, the proteins for human grade food, the polyunsaturated fatty acids as a high value nutritional supplement as well as other value-added products.
In order to select the most efficient and sustainable method, a critical analysis of the sustainability of the different methods to grow algae for biofuels was also performed, using all data available in the literature. It became apparent from the information reported so far from over 40 funded fuel-from-algae projects, that we have designed and developed the only truly sustainable technology known to date.
An important conclusion we have learned through the testing of the Geo-Solar system for growing algae was that even greater results could be achieved if we solve the problem for retaining the gained energy by the Geo-Solar system. The problem could be solved by incorporating a dynamic insulation barrier between the double polyethylene layers of the High Tunnel cover, for which we had already applied for a SARE Grant in 2008 and again in 2009. Approval of this Grant application will have a very important consequence for the algae-for-biofuel project. It could potentially reduce more than 50% the energy losses from the system.
WORK PLAN FOR 2010
The focus will be on algae oil extraction using Supercritical Fluid Extraction with carbon dioxide as the extracting supercritical solvent. In parallel efforts, we will continue work on further scale up of algae bioreactors and optimization of the growing conditions for maximum yield of biomass and oil.
In addition we will perform experiments to test any new emerging methods for separation of the algae biomass and oil extraction to evaluate and compare their efficiency and cost effectiveness.
To achieve this goal an extension of time was requested from NCR-SARE.
The requested extension does not require any additional funding but only extra time to complete the necessary testing, prior to scale up of the new technology.
The request for extension with the new final report date of March 1, 2011, was granted, which will allow us to complete the project successfully. The successful completion will be important and beneficial to the entire farming community and beyond to the National Initiative for Foreign Independence of Fuels, the issues with global warming and the problems with nutrition resources around the world.
The general ideas and approach for the project have been presented at a meeting of up to 100 people, several potential grant funding organizations, universities and companies working in this area. Due to the potential of patenting some of the results, some details from the project may not be available for the public domain until the proper patent application procedures are completed.