Algal fuel

Algae fuel, also called algal fuel, oilgae^[1] or third generation biofuel ^[2] , is a biofuel from algae. Compared with second generation biofuels, algae are high-yield high-cost (30 times more energy per acre than terrestrial crops) feedstocks to produce biofuels. Since the whole organism converts sunlight into oil, algae can produce more oil in an area the size of a two-car garage than an entire football field of soybeans.^[3]

Nowadays they cost $5–10/kg and there is active research to reduce both capital and operating costs of production so that it is commercially viable.^[4]^[5]

The production of biofuels to replace oil and natural gas is in active development, focusing on the use of cheap organic matter (usually cellulose, agricultural and sewage waste)^[7] in the efficient production of liquid and gas biofuels which yield high net energy gain. One advantage of many biofuels over most other fuel types is that they are biodegradable, and so relatively harmless to the environment if spilled.^[8]^[9]^[10]

History

The Aquatic Species Program was a research program in the United States launched in 1978 by President Jimmy Carter and was funded by the United States Department of Energy, ^[15] which over the course of nearly two decades looked into the production of energy using algae, later on the aim of the program was focused to the production of bio-diesel from algae. The research program was discontinued by the Clinton administration in 1996. The DOE research staff compiled their work and conclusions into a report that was published in July 1998.

In 2008, Time Magazine voted Isaac Berzin as one of the world's most influential for 2008 for his ability to turn a dream of an oil-free future into a reality through GreenFuel, the company he founded in Boston in 2001.

Factors

Dry algae factor is the percentage of algae cells in relation with the media where is cultured. I.e., if the dry algae factor is 50%, one would need 2 kg of wet algae (algae in the media) to get 1 kg of algae cells.

Lipid factor is the percentage of vegoil in relation with the algae cells needed to get it I.e., if the algae lipid factor is 40%, one need 2.5 kg of algae cells to get 1 kg of oil.

Fuels

The vegoil algae produce can then be harvested and converted into biodiesel; the algae’s carbohydrate content can be fermented into bioethanol.^[16]

Biodiesel production

Currently most research into efficient algal-oil production is being done in the private sector, but predictions from small scale production experiments bear out that using algae to produce biodiesel may be the only viable method by which to produce enough automotive fuel to replace current world diesel usage.^[17]

Microalgae have much faster growth-rates than terrestrial crops. The per unit area yield of oil from algae is estimated to be from between 5,000 to 20,000 gallons per acre, per year (4.6 to 18.4 l/m² per year); this is 7 to 30 times greater than the next best crop, Chinese tallow (699 gallons).^[18]

Algae can also grow on marginal lands, such as in desert areas where the groundwater is saline.^[19]

The difficulties in efficient biodiesel production from algae lie in finding an algal strain with a high lipid content and fast growth rate that isn't too difficult to harvest, and a cost-effective cultivation system (i.e., type of photobioreactor) that is best suited to that strain.

Another obstacle preventing widespread mass production of algae for biofuel production has been the equipment and structures needed to begin growing algae in large quantities. Diversified Energy Corporation have avoided this problem by taking a different approach, and growing the algae in thin walled polyethylene tubing called Algae Biotape, similar to conventional drip irrigation tubing, which can be incorporated into a normal agricultural environment.^[20]

Open-pond systems for the most part have been given up for the cultivation of algae with high-oil content.^[21] Many believe that a major flaw of the Aquatic Species Program was the decision to focus their efforts exclusively on open-ponds; this makes the entire effort dependent upon the hardiness of the strain chosen, requiring it to be unnecessarily resilient in order to withstand wide swings in temperature and pH, and competition from invasive algae and bacteria. Open systems using a monoculture are also vulnerable to viral infection. The energy that a high-oil strain invests into the production of oil is energy that is not invested into the production of proteins or carbohydrates, usually resulting in the species being less hardy, or having a slower growth rate. Algal species with a lower oil content, not having to divert their energies away from growth, have an easier time in the harsher conditions of an open system.

In a closed system (not exposed to open air) there is not the problem of contamination by other organisms blown in by the air. The problem for a closed system is finding a cheap source of sterile carbon dioxide (CO₂). Several experimenters have found the CO₂ from a smokestack works well for growing algae.^[23]^[24] To be economical, some experts think that algae farming for biofuels will have to be done next to power plants, where they can also help soak up the pollution.^[19]

A feasibility study using marine microalgae in a photobioreactor is being done by The International Research Consortium on Continental Margins at the International University Bremen.^[25]

Research into algae for the mass-production of oil is mainly focused on microalgae; organisms capable of photosynthesis that are less than 2 mm in diameter, including the diatoms and cyanobacteria; as opposed to macroalgae, e.g. seaweed. However, some research is being done into using seaweeds for biofuels, probably due to the high availability of this resource.^[26] This preference towards microalgae is due largely to its less complex structure, fast growth rate, and high oil content (for some species). Some commercial interests into large scale algal-cultivation systems are looking to tie in to existing infrastructures, such as coal power plants or sewage treatment facilities. This approach not only provides the raw materials for the system, such as CO₂ and nutrients; but it changes those wastes into resources.

In November 8, 2006, Green Star Products announced it had signed an agreement with De Beers Fuel Limited of South Africa (but no relation to the diamond cartel) to build 90 biodiesel reactors with algae as raw material. Each of the biodiesel reactors will be capable of producing 10 million gallons of biodiesel each year for a total production capacity of 900,000,000 gallons per year when operating at full capacity, which is 4 times greater than the entire U.S. output in 2006. Also, GreenFuel Technologies Corporation has delivered a bioreactor to De Beers Fuel. Doubts have been expressed about Green Star's expertise in biodiesel technology.^[27] Green Star's president did however answer questions in an online interview with WallSt.net where he claimed that the South African biodiesel production has exceeded the original expectations.^[28] People who paid De Beers Fuel for franchises have nothing to show for their investment.^[29] GreenFuel has terminated its licensing agreement with De Beers Fuel owing to “nonperformance” and requested that the company remove any reference to the agreement from its website.^[30]

Aquaflow Bionomic Corporation of New Zealand announced that it has produced its first sample of homegrown bio-diesel fuel with algae sourced from local sewerage ponds.

The Department of Environmental Science at Ateneo de Manila University in the Philippines, is working on producing biofuel from algae, using a local species of algae.^[31]

PetroSun has announced it has begun operation of its commercial algae-to-biofuels facility on April 1st, 2008. The facility, located in Rio Hondo, Texas, will produce an estimated 4.4 million US gallons (17 million l) of algal oil and 110 million pounds (50 million kg) of biomass per year off a series of saltwater ponds spanning 1,100 acres (4.5 km²). Twenty acres (8.1 ha) will be reserved for the experimental production of a renewable JP8 jet-fuel.^[6]

Biobutanol

Butanol can be made from algae or diatoms using only a solar powered biorefinery. This fuel has an energy density similar to, but greater than that of gasoline (petroleum gasoline).

The green waste made from the algae oil extraction can be used to produce butanol.

Biogasoline

Methane

Through the use of algaculture grown organisms and cultures, various polymeric materials can be broken down into methane.^[32]

SVO

The algal-oil feedstock that is used to produce biodiesel can also be used for fuel directly as "Straight Vegetable Oil", (SVO). The benefit of using the oil in this manner is that it doesn't require the additional energy needed for transesterification, (processing the oil with an alcohol and a catalyst to produce biodiesel). The drawback is that it does require modifications to a normal diesel engine. Transesterified biodiesel can be run in an unmodified modern diesel engine, provided the engine is designed to use ultra-low sulfur diesel, which, as of 2006, is the new diesel fuel standard in the United States.

Hydrocracking to traditional transport fuels

DIY, small and open source technology production

People can grow their own fuel at home, on the roofs of their homes, using open source technologies. A 185 m² (2,000 square foot) home could produce 10 US gallons (38 l) of algal diesel a week. It could supply the needs of either a single truck or a family of efficient cars.^{citation needed}

The average car in the U.S.A. is driven between 15,000 miles (24,000 km) to 25,000 miles (40,000 km) a year. And if we assume that the average car can get 25 mpg–U.S. (9.41 L/100 km / 30 mpg–imp), we get the total amount of gas a year. That would be 15000/25 = 600 US gallons (2,300 l) and 25000 / 25 = 1,000 US gallons (3,800 l) per year.

Biofuel from algae by territory

Organizations

Tweinty-five airlines went bust or stopped operations in the first six months of 2008 and more could fold as fuel prices soar, aviation industry association IATA has warned ^[38] . Algal jet fuel can be used as alternative: IATA recognizes that aircraft are long lived and will be using kerosene or kerosene type fuels for many years. It supports research, development & deployment into alternative fuels that produce less GHG emissions over their life cycle and do not compete for land with fuel crops. IATA’s goal is for its members to be using 10% alternative fuels by 2017^[39].

Algae cultivation

Algae grow rapidly and can have a high percentage of lipids, or oils. They can double their mass several times a day and produce at least 15 times more oil per acre than alternatives such as rapeseed, palms, soybeans, or jatropha. Moreover, algae-growing facilities can be built on coastal land unsuitable for conventional agriculture.

The hard part about algae production is growing the algae in a controlled way and harvesting it efficiently.

Most companies pursuing algae as a source of biofuels are pumping nutrient-laden water through plastic tubes (called "bioreactors" ) that are exposed to sunlight (and so called photobioreactors or PBR).

Wastewater

Algal strains

Nutrients

Fertilizers, like nitrogen (N), phosphorous (P), and potassium (K), are important for plant growth and are called nutrients. Silica and iron may also be considered important marine nutrients as their lack can limit the amount of productivity in an area.^[42]

Another possible source is sewer treatment effluent, full of nutrients and discarded every day.

One can not directly feed organic waste to the algae, because one needs to transform it into fertilizers by means of anaerobic digestion, that is done by using anaerobic bacteria. If one place waste into your pond (or some reactor section), it will infect algae, and there are no anaerobic conditions either. In a biogas facility, one puts organic waste and after a while gets CO2/methane mixture and organic fertilizer. Organic fertilizer that comes out of digester is liquid, but it must be cleaned of the particles and sterilized.

Green Star Products, Inc. announced its development of a micronutrient formula to increase the growth rate of algae. According to the company, its new formula can increase the daily growth rate by 34% and can double the amount of algae produced in one growth cycle.^[45]

Contents