Algae fuel is a fuel based on lipids extracted from micro-algae. The algofuels are “third generation” biofuels potentially able to replace the controversial “first generation” biodiesels, obtained from vegetable oil of terrestrial plants. Algae fuel, algae biofuel or seaweed oil is an alternative to liquid fossil fuels that use algae as a source of high energy oils. Like fossil fuel, algae fuel releases CO2 when burned, but unlike fossil fuel, fuel based on algae and other biofuels releases only CO2 recently removed from the atmosphere by photosynthesis as algae or plants grow.
The energy crisis and the global food crisis have sparked interest in growing algae for the production of biodiesel and other biofuels on land unsuitable for conventional agriculture. Some of the attractive characteristics of algae-based fuels are that they could be grown with minimal impact on freshwater resources, can be produced using saline and wastewater, and are biodegradable and relatively harmless. in the event of a spill in the natural environment.
The biofuel produced entirely from algae is considered an energy of 3th generation, but its production is not yet at the point.
Algae are the first component of kerogen, from which oil is derived.
Photosynthesis of micro-algae
The diatoms and Chlorophyta have a photosynthetic process similar to that of higher plants. They are able to fix, as terrestrial plants do, CO2 thanks to the enzyme Rubisco (Ribulose bisphosphate carboxylase). The products of the Calvin cycle serve as a starting point for the biosynthesis of sugars or lipids. The enzyme acetylcoenzyme A carboxylase (ACCase) plays a key role, especially in diatoms, in the synthesis pathway of triglycerides or triacylglycerols (TAG), molecules sought for obtaining fuels. A silica deficiency induced in diatoms increased lipid synthesis, this in connection with the activity of ACCase gene. This gene has been isolated and cloned in order to seek to increase its expression and thus the production of oil. Nitrogen stress in green algae is accompanied by the same effects.
There are different types of returns.
The yield of biomass characterizes the production of living matter, this yield is a basis of comparison for sources of biofuels (cereals, algae, trees, etc.). This yield is particularly used in the analysis of oil replacement by equivalent renewable energy (liquid, with little modification of existing systems such as engines).
Energy efficiency characterizes the final output of energy, regardless of its form (fuel or electricity). It is a global comparison indicator.
According to the Shamash research program, coordinated by INRIA, some microalgae “can accumulate up to 50% of their dry weight in fatty acids”. The microalgae tested are diatoms and chlorophycea.
According to IFREMER, “it is estimated that there are between 200,000 and one million algal species in the world. This biological diversity, responding to an exceptional adaptability, allows to prejudge a proportional richness in original molecules and lipids (algo-fuels). In comparison with terrestrial oil species, microalgae have many favorable characteristics for the production of fatty acids that could be used to produce algo-fuels. The main assets are about 10 times higher biomass yield and no conflict with freshwater and agricultural land. The production could represent 20000 to 60000 liters of oil per hectare per year against6000 liters for palm oil, one of the best land-based yields. »
According to Yusuf Chisti of Massey University in New Zealand (Institute of Technology and Engineering), the yield of diatoms and chlorophycea is much higher than that of terrestrial plants such as rape because they are unicellular organisms; their growth in suspension in an aqueous medium allows them better access to resources: water, CO2 or minerals. According to scientists at the National Renewable Energy Laboratory (NREL), microscopic algae are able to ” synthesize 10 times to 100 more oil per hectare than terrestrial oil plants used to make agrofuels.”.
The fuels needed for road transport in the United States could be covered by the production of algofuels over an area of 90 000 km 2, roughly the total area of Hungary. A performance to compare with that of palm oil, which for the same use would require the total area of a country like Pakistan. A researcher who conducted a study for the Department of Energy of the United States believes meanwhile that the fuel used today in the United States could be produced on a smaller surface area equivalent to that of the State of Maryland that 27 091 km2, or a square of 165 km on the side. In comparison, the Sahara represents 9,400,000 km2.
The report “Agrofuels and Environment” published in late 2008 in France by the Ministry of Ecology, states for its part that the conversion efficiency of solar energy by microalgae is of the order of W m2, that is two to ten times less than wind energy (between 5 and 20 W m2), or mountain hydroelectricity (between 10 and 50 W m2). The conclusion drawn by this report is that”The agrofuels are in the zone of the lowest yields, they are actually limited by the yield of photosynthesis which is very low (<1%). The third generation, using algae, will remain largely less effective than any “electrical” solutions, including the use of solar energy, ” so agrofuels have no other justification than that to provide usable fuel for transport alternatives to fossil fuels”.
Estimates of the cost of industrial production differ.
The French scientific team Shamash evaluates in January 2009at 10 euros per liter the cost of industrial production of the algocarburant.
A Canadian company, Seed Science Ltd estimates the cost of industrial production in developed countries at a figure of between 3.5 and 6.9 euros per liter (between $ 4.5 and $ 9).
The program Biomass, the US Department of Energy estimates the cost of industrial production to more than 8 $ per gallon, or 1.80 euros per liter, given the known dataNovember 2008.
Algenol announces a low-cost distribution of $ 1.30 per gallon in 2015 18, or € 0.30 per liter.
In comparison with terrestrial-based biofuel crops such as corn or soybeans, microalgal production results in a much less significant land footprint due to the higher oil productivity from the microalgae than all other oil crops. Algae can also be grown on marginal lands useless for ordinary crops and with low conservation value, and can use water from salt aquifers that is not useful for agriculture or drinking. Algae can also grow on the surface of the ocean in bags or floating screens. Thus microalgae could provide a source of clean energy with little impact on the provisioning of adequate food and water or the conservation of biodiversity. Algae cultivation also requires no external subsidies of insecticides or herbicides, removing any risk of generating associated pesticide waste streams. In addition, algal biofuels are much less toxic, and degrade far more readily than petroleum-based fuels. However, due to the flammable nature of any combustible fuel, there is potential for some environmental hazards if ignited or spilled, as may occur in a train derailment or a pipeline leak. This hazard is reduced compared to fossil fuels, due to the ability for algal biofuels to be produced in a much more localized manner, and due to the lower toxicity overall, but the hazard is still there nonetheless. Therefore, algal biofuels should be treated in a similar manner to petroleum fuels in transportation and use, with sufficient safety measures in place at all times.
Studies have determined that replacing fossil fuels with renewable energy sources, such as biofuels, have the capability of reducing CO2 emissions by up to 80%. An algae-based system could capture approximately 80% of the CO2 emitted from a power plant when sunlight is available. Although this CO2 will later be released into the atmosphere when the fuel is burned, this CO2 would have entered the atmosphere regardless. The possibility of reducing total CO2 emissions therefore lies in the prevention of the release of CO2 from fossil fuels. Furthermore, compared to fuels like diesel and petroleum, and even compared to other sources of biofuels, the production and combustion of algal biofuel does not produce any sulfur oxides or nitrous oxides, and produces a reduced amount of carbon monoxide, unburned hydrocarbons, and reduced emission of other harmful pollutants. Since terrestrial plant sources of biofuel production simply do not have the production capacity to meet current energy requirements, microalgae may be one of the only options to approach complete replacement of fossil fuels.
Microalgae production also includes the ability to use saline waste or waste CO2 streams as an energy source. This opens a new strategy to produce biofuel in conjunction with waste water treatment, while being able to produce clean water as a byproduct. When used in a microalgal bioreactor, harvested microalgae will capture significant quantities of organic compounds as well as heavy metal contaminants absorbed from wastewater streams that would otherwise be directly discharged into surface and ground-water. Moreover, this process also allows the recovery of phosphorus from waste, which is an essential but scarce element in nature – the reserves of which are estimated to have depleted in the last 50 years. Another possibility is the use of algae production systems to clean up non-point source pollution, in a system known as an algal turf scrubber (ATS). This has been demonstrated to reduce nitrogen and phosphorus levels in rivers and other large bodies of water affected by eutrophication, and systems are being built that will be capable of processing up to 110 million liters of water per day. ATS can also be used for treating point source pollution, such as the waste water mentioned above, or in treating livestock effluent.
Nearly all research in algal biofuels has focused on culturing single species, or monocultures, of microalgae. However, ecological theory and empirical studies have demonstrated that plant and algae polycultures, i.e. groups of multiple species, tend to produce larger yields than monocultures. Experiments have also shown that more diverse aquatic microbial communities tend to be more stable through time than less diverse communities. Recent studies found that polycultures of microalgae produced significantly higher lipid yields than monocultures. Polycultures also tend to be more resistant to pest and disease outbreaks, as well as invasion by other plants or algae. Thus culturing microalgae in polyculture may not only increase yields and stability of yields of biofuel, but also reduce the environmental impact of an algal biofuel industry.
There is clearly a demand for sustainable biofuel production, but whether a particular biofuel will be used ultimately depends not on sustainability but cost efficiency. Therefore, research is focusing on cutting the cost of algal biofuel production to the point where it can compete with conventional petroleum. The production of several products from algae has been mentioned[weasel words] as the most important factor for making algae production economically viable. Other factors are the improving of the solar energy to biomass conversion efficiency (currently 3%, but 5 to 7% is theoretically attainable)and making the oil extraction from the algae easier.
In a 2007 report a formula was derived estimating the cost of algal oil in order for it to be a viable substitute to petroleum diesel:
C(algal oil) = 25.9 × 10−3 C(petroleum)
where: C(algal oil) is the price of microalgal oil in dollars per gallon and C(petroleum) is the price of crude oil in dollars per barrel. This equation assumes that algal oil has roughly 80% of the caloric energy value of crude petroleum.
With current technology available, it is estimated that the cost of producing microalgal biomass is $2.95/kg for photobioreactors and $3.80/kg for open-ponds. These estimates assume that carbon dioxide is available at no cost. If the annual biomass production capacity is increased to 10,000 tonnes, the cost of production per kilogram reduces to roughly $0.47 and $0.60, respectively. Assuming that the biomass contains 30% oil by weight, the cost of biomass for providing a liter of oil would be approximately $1.40 ($5.30/gal) and $1.81 ($6.85/gal) for photobioreactors and raceways, respectively. Oil recovered from the lower cost biomass produced in photobioreactors is estimated to cost $2.80/L, assuming the recovery process contributes 50% to the cost of the final recovered oil. If existing algae projects can achieve biodiesel production price targets of less than $1 per gallon, the United States may realize its goal of replacing up to 20% of transport fuels by 2020 by using environmentally and economically sustainable fuels from algae production.
Whereas technical problems, such as harvesting, are being addressed successfully by the industry, the high up-front investment of algae-to-biofuels facilities is seen by many as a major obstacle to the success of this technology. Only few studies on the economic viability are publicly available, and must often rely on the little data (often only engineering estimates) available in the public domain. Dmitrov examined the GreenFuel’s photobioreactor and estimated that algae oil would only be competitive at an oil price of $800 per barrel. A study by Alabi et al. examined raceways, photobioreactors and anaerobic fermenters to make biofuels from algae and found that photobioreactors are too expensive to make biofuels. Raceways might be cost-effective in warm climates with very low labor costs, and fermenters may become cost-effective subsequent to significant process improvements. The group found that capital cost, labor cost and operational costs (fertilizer, electricity, etc.) by themselves are too high for algae biofuels to be cost-competitive with conventional fuels. Similar results were found by others, suggesting that unless new, cheaper ways of harnessing algae for biofuels production are found, their great technical potential may never become economically accessible. Recently, Rodrigo E. Teixeira demonstrated a new reaction and proposed a process for harvesting and extracting raw materials for biofuel and chemical production that requires a fraction of the energy of current methods, while extracting all cell constituents.
Use of Byproducts
Many of the byproducts produced in the processing of microalgae can be used in various applications, many of which have a longer history of production than algal biofuel. Some of the products not used in the production of biofuel include natural dyes and pigments, antioxidants, and other high-value bio-active compounds. These chemicals and excess biomass have found numerous use in other industries. For example, the dyes and oils have found a place in cosmetics, commonly as thickening and water-binding agents. Discoveries within the pharmaceutical industry include antibiotics and antifungals derived from microalgae, as well as natural health products, which have been growing in popularity over the past few decades. For instance Spirulina contains numerous polyunsaturated fats (Omega 3 and 6), amino acids, and vitamins, as well as pigments that may be beneficial, such as beta-carotene and chlorophyll.
Ease of growth
One of the main advantages that using microalgae as the feedstock when compared to more traditional crops is that it can be grown much more easily. Algae can be grown in land that would not be considered suitable for the growth of the regularly used crops. In addition to this, wastewater that would normally hinder plant growth has been shown to be very effective in growing algae. Because of this, algae can be grown without taking up arable land that would otherwise be used for producing food crops, and the better resources can be reserved for normal crop production. Microalgae also require fewer resources to grow and little attention is needed, allowing the growth and cultivation of algae to be a very passive process.
Impact on food
Many traditional feedstocks for biodiesel, such as corn and palm, are also used as feed for livestock on farms, as well as a valuable source of food for humans. Because of this, using them as biofuel reduces the amount of food available for both, resulting in an increased cost for both the food and the fuel produced. Using algae as a source of biodiesel can alleviate this problem in a number of ways. First, algae is not used as a primary food source for humans, meaning that it can be used solely for fuel and there would be little impact in the food industry. Second, many of the waste-product extracts produced during the processing of algae for biofuel can be used as a sufficient animal feed. This is an effective way to minimize waste and a much cheaper alternative to the more traditional corn- or grain-based feeds.
Minimalisation of waste
Growing algae as a source of biofuel has also been shown to have numerous environmental benefits, and has presented itself as a much more environmentally friendly alternative to current biofuels. For one, it is able to utilize run-off, water contaminated with fertilizers and other nutrients that are a by-product of farming, as its primary source of water and nutrients. Because of this, it prevents this contaminated water from mixing with the lakes and rivers that currently supply our drinking water. In addition to this, the ammonia, nitrates, and phosphates that would normally render the water unsafe actually serve as excellent nutrients for the algae, meaning that fewer resources are needed to grow the algae. Many algae species used in biodiesel production are excellent bio-fixers, meaning they are able to remove carbon dioxide from the atmosphere to use as a form of energy for themselves. Because of this, they have found use in industry as a way to treat flue gases and reduce GHG emissions.
Algae biodiesel is still a fairly new technology. Despite the fact that research began over 30 years ago, it was put on hold during the mid-1990s, mainly due to a lack of funding and a relatively low petroleum cost. For the next few years algae biofuels saw little attention; it was not until the gas peak of the early 2000s that it eventually had a revitalization in the search for alternative fuel sources. While the technology exists to harvest and convert algae into a usable source of biodiesel, it still hasn’t been implemented into a large enough scale to support the current energy needs. Further research will be required to make the production of algae biofuels more efficient, and at this point it is currently being held back by lobbyists in support of alternative biofuels, like those produced from corn and grain. In 2013, Exxon Mobil Chairman and CEO Rex Tillerson said that after originally committing to spending up to $600 million on development in a joint venture with J. Craig Venter’s Synthetic Genomics, algae is “probably further” than “25 years away” from commercial viability, although Solazyme and Sapphire Energy already began small-scale commercial sales in 2012 and 2013, respectively. By 2017, most efforts had been abandoned or changed to other applications, with only a few remaining.
The biodiesel produced from the processing of microalgae differs from other forms of biodiesel in the content of polyunsaturated fats. Polyunsaturated fats are known for their ability to retain fluidity at lower temperatures. While this may seem like an advantage in production during the colder temperatures of the winter, the polyunsaturated fats result in lower stability during regular seasonal temperatures.
The National Renewable Energy Laboratory (NREL) is the U.S. Department of Energy’s primary national laboratory for renewable energy and energy efficiency research and development. This program is involved in the production of renewable energies and energy efficiency. One of its most current divisions is the biomass program which is involved in biomass characterization, biochemical and thermochemical conversion technologies in conjunction with biomass process engineering and analysis. The program aims at producing energy efficient, cost-effective and environmentally friendly technologies that support rural economies, reduce the nations dependency in oil and improve air quality.
At the Woods Hole Oceanographic Institution and the Harbor Branch Oceanographic Institution the wastewater from domestic and industrial sources contain rich organic compounds that are being used to accelerate the growth of algae. The Department of Biological and Agricultural Engineering at University of Georgia is exploring microalgal biomass production using industrial wastewater. Algaewheel, based in Indianapolis, Indiana, presented a proposal to build a facility in Cedar Lake, Indiana that uses algae to treat municipal wastewater, using the sludge byproduct to produce biofuel. A similar approach is being followed by Algae Systems, a company based in Daphne, Alabama.
Sapphire Energy (San Diego) has produced green crude from algae.
Solazyme (South San Francisco, California) has produced a fuel suitable for powering jet aircraft from algae.
The Marine Research station in Ketch Harbour, Nova Scotia, has been involved in growing algae for 50 years. The National Research Council (Canada) (NRC) and National Byproducts Program have provided $5 million to fund this project. The aim of the program has been to build a 50 000 litre cultivation pilot plant at the Ketch harbor facility. The station has been involved in assessing how best to grow algae for biofuel and is involved in investigating the utilization of numerous algae species in regions of North America. NRC has joined forces with the United States Department of Energy, the National Renewable Energy Laboratory in Colorado and Sandia National Laboratories in New Mexico.
Universities in the United Kingdom which are working on producing oil from algae include: University of Manchester, University of Sheffield, University of Glasgow, University of Brighton, University of Cambridge, University College London, Imperial College London, Cranfield University and Newcastle University. In Spain, it is also relevant the research carried out by the CSIC´s Instituto de Bioquímica Vegetal y Fotosíntesis (Microalgae Biotechnology Group, Seville).
The European Algae Biomass Association (EABA) is the European association representing both research and industry in the field of algae technologies, currently with 79 members. The association is headquartered in Florence, Italy. The general objective of the EABA is to promote mutual interchange and cooperation in the field of biomass production and use, including biofuels uses and all other utilisations. It aims at creating, developing and maintaining solidarity and links between its Members and at defending their interests at European and international level. Its main target is to act as a catalyst for fostering synergies among scientists, industrialists and decision makers to promote the development of research, technology and industrial capacities in the field of Algae.
CMCL innovations and the University of Cambridge are carrying out a detailed design study of a C-FAST (Carbon negative Fuels derived from Algal and Solar Technologies) plant. The main objective is to design a pilot plant which can demonstrate production of hydrocarbon fuels (including diesel and gasoline) as sustainable carbon-negative energy carriers and raw materials for the chemical commodity industry. This project will report in June 2013.
Ukraine plans to produce biofuel using a special type of algae.
The European Commission’s Algae Cluster Project, funded through the Seventh Framework Programme, is made up of three algae biofuel projects, each looking to design and build a different algae biofuel facility covering 10ha of land. The projects are BIOFAT, All-Gas and InteSusAl.
Since various fuels and chemicals can be produced from algae, it has been suggested to investigate the feasibility of various production processes(conventional extraction/separation, hydrothermal liquefaction, gasification and pyrolysis) for application in an integrated algal biorefinery.
Reliance industries in collaboration with Algenol, USA commissioned a pilot project to produce algal bio-oil in the year 2014. Spirulina which is an alga rich in proteins content has been commercially cultivated in India. Algae is used in India for treating the sewage in open/natural oxidation ponds This reduces the Biological Oxygen Demand (BOD) of the sewage and also provides algal biomass which can be converted to fuel.
The Algae Biomass Organization (ABO) is a non-profit organization whose mission is “to promote the development of viable commercial markets for renewable and sustainable commodities derived from algae”.
The National Algae Association (NAA) is a non-profit organization of algae researchers, algae production companies and the investment community who share the goal of commercializing algae oil as an alternative feedstock for the biofuels markets. The NAA gives its members a forum to efficiently evaluate various algae technologies for potential early stage company opportunities.
Pond Biofuels Inc. in Ontario, Canada has a functioning pilot plant where algae is grown directly off of smokestack emissions from a cement plant, and dried using waste heat. In May 2013, Pond Biofuels announced a partnership with the National Research Council of Canada and Canadian Natural Resources Limited to construct a demonstration-scale algal biorefinery at an oil sands site near Bonnyville, Alberta.
Ocean Nutrition Canada in Halifax, Nova Scotia, Canada has found a new strain of algae that appears capable of producing oil at a rate 60 times greater than other types of algae being used for the generation of biofuels.
VG Energy, a subsidiary of Viral Genetics Incorporated, claims to have discovered a new method of increasing algal lipid production by disrupting the metabolic pathways that would otherwise divert photosynthetic energy towards carbohydrate production. Using these techniques, the company states that lipid production could be increased several-fold, potentially making algal biofuels cost-competitive with existing fossil fuels.
Algae production from the warm water discharge of a nuclear power plant has been piloted by Patrick C. Kangas at Peach Bottom Nuclear Power Station, owned by Exelon Corporation. This process takes advantage of the relatively high temperature water to sustain algae growth even during winter months.
Companies such as Sapphire Energy and Bio Solar Cells are using genetic engineering to make algae fuel production more efficient. According to Klein Lankhorst of Bio Solar Cells, genetic engineering could vastly improve algae fuel efficiency as algae can be modified to only build short carbon chains instead of long chains of carbohydrates. Sapphire Energy also uses chemically induced mutations to produce algae suitable for use as a crop.
Some commercial interests into large-scale algal-cultivation systems are looking to tie into existing infrastructures, such as cement factories, coal power plants, or sewage treatment facilities. This approach changes wastes into resources to provide the raw materials, CO2 and nutrients, for the system.
A feasibility study using marine microalgae in a photobioreactor is being done by The International Research Consortium on Continental Margins at the Jacobs University Bremen.
The Department of Environmental Science at Ateneo de Manila University in the Philippines, is working on producing biofuel from a local species of algae.
Genetic engineering algae has been used to increase lipid production or growth rates. Current research in genetic engineering includes either the introduction or removal of enzymes. In 2007 Oswald et al. introduced a monoterpene synthase from sweet basil into Saccharomyces cerevisiae, a strain of yeast. This particular monoterpene synthase causes the de novo synthesis of large amounts of geraniol, while also secreting it into the medium. Geraniol is a primary component in rose oil, palmarosa oil, and citronella oil as well as essential oils, making it a viable source of triacylglycerides for biodiesel production.
The enzyme ADP-glucose pyrophosphorylase is vital in starch production, but has no connection to lipid synthesis. Removal of this enzyme resulted in the sta6 mutant, which showed increased lipid content. After 18 hours of growth in nitrogen deficient medium the sta6 mutants had on average 17 ng triacylglycerides/1000 cells, compared to 10 ng/1000 cells in WT cells. This increase in lipid production was attributed to reallocation of intracellular resources, as the algae diverted energy from starch production.
In 2013 researchers used a “knock-down” of fat-reducing enzymes (multifunctional lipase/phospholipase/acyltransferase) to increase lipids (oils) without compromising growth. The study also introduced an efficient screening process. Antisense-expressing knockdown strains 1A6 and 1B1 contained 2.4- and 3.3-fold higher lipid content during exponential growth, and 4.1- and 3.2-fold higher lipid content after 40 h of silicon starvation.
Numerous Funding programs have been created with aims of promoting the use of Renewable Energy. In Canada, the ecoAgriculture biofuels capital initiative (ecoABC) provides $25 million per project to assist farmers in constructing and expanding a renewable fuel production facility. The program has $186 million set aside for these projects. The sustainable development (SDTC) program has also applied $500 millions over 8 years to assist with the construction of next-generation renewable fuels. In addition, over the last 2 years $10 million has been made available for renewable fuel research and analysis
In Europe, the Seventh Framework Programme (FP7) is the main instrument for funding research. Similarly, the NER 300 is an unofficial, independent portal dedicated to renewable energy and grid integration projects. Another program includes the Horizon 2020 program which will start 1 January, and will bring together the framework program and other EC innovation and research funding into a new integrated funding system
The American NBB’s Feedstock Development program is addressing production of algae on the horizon to expand available material for biodiesel in a sustainable manner.
Source from Wikipedia