Algae as energy vegetation is considered to be a very promising renewable raw material for the production of biofuels in the world today.
But why algae is so special?
Biofuels as an alternative source of energy are of particular interest to study, because they would help solve such problems as the depletion of oil reserves and global warming. Unlike oil, biofuels are produced from renewable natural resources, and when they are burned, less greenhouse gases are emitted. Brazil, for example, already provides 40% of its needs with biofuels. Agricultural crops and other plants are used as raw materials for biofuels. However, in this case, you have to occupy fertile land that could feed people instead. A promising feedstock for biofuels is marine microalgae, which require neither clean water nor land. Algae actively absorb carbon dioxide, which means that their use is really useful for reducing the greenhouse effect. Microalgae fuels are referred to as third generation biofuels and are currently under active development to produce them.
Algae is a significant improvement over alternative biofuel sources for several reasons:
- Unlike ethanol and biodiesel production, algae production does not compete with food sources by converting algae into flour.
- Because algae can be produced in salt water, including seawater, their production will not deplete fresh water resources, as is the case with ethanol production.
- Algae consume CO2 and have much lower emissions throughout their life cycle than corn ethanol, given the energy used to make fertilizers, purify ethanol, and process and transport it.
- Algae can produce more biofuels per unit area than crop biofuels: currently about 1,500 gallons of fuel per acre per year. That’s nearly five times more fuel per acre than using sugarcane or corn.
Cultivation features and world research. How algal fuel is gaining global attention
The US Department of Energy has tested high oil content algae under the Aquatic Species Program. The researchers concluded that California, Hawaii and New Mexico are suitable for industrial production of algae in open ponds. For 6 years, algae has been grown in 1000 m2 ponds. A pond in New Mexico has been shown to be highly effective in capturing CO2. The yield was more than 50 grams. algae from 1 m2 per day.
In addition to growing algae in open ponds, there are technologies for growing algae in small bioreactors located near power plants. The waste heat of the CHP plant is capable of covering up to 77% of the heat needs for algae growing. This technology does not require a hot desert climate.
BioKing (Hangzhou Bioking Biochemical Engineering Co., Ltd.) has begun mass production of its patented, out-of-the-box algae bioreactors, which include fast growing algae with a high oil content.
Spanish scientists have found one of the types of microalgae that are able to reproduce much faster than other biological counterparts under certain lighting conditions. If in the open sea each cubic meter of water accounts for up to 300 specimens of algae, then the researchers received 200 million specimens for the same cubic meter of water.
Microalgae grow in a plastic cylinder 70 cm in diameter and 3 m long. Algae reproduce by division. They divide every 12 hours, and gradually the water in the cylinder turns into a green dense mass. Once a day, the contents of the cylinder are centrifuged. The remainder is almost 100% biofuel. Part of this mass saturated with fats is converted into biodiesel, and hydrocarbons – into ethanol.
ExxonMobil’s global endeavor
Today, ExxonMobil and Viridos (formerly Synthetic Genomics, Inc.; a California-based biotechnology company
harnessing the power of photosynthesis to create transformative solutions to mitigate climate change) are conducting a basic research program to develop advanced algal biofuels. The joint effort aims to achieve the technical capacity to produce 10,000 barrels of algae biofuel per day by 2025. Their goal is both to develop advanced algal biofuels and to make these revolutionary technologies available to consumers. The program includes, among other things, the entire amount of data we received, it represents all the progress that they have achieved since the very beginning of cooperation with Viridos in 2009.
Using advanced cell engineering technologies at Viridos, the joint research group ExxonMobil and Viridos recently modified algae to increase the oil content from 20% to 40% or more.
Researchers at the Viridos lab in La Jolla have discovered a new process for increasing oil production by identifying a genetic switch that could be fine-tuned to regulate the conversion of carbon to oil in Nannochloropsis gaditana algae. The team established a conceptual approach that resulted in the algae doubling their lipid fraction of cellular carbon compared to their parent – while maintaining growth.
The ability to support growth while increasing oil content is an important step forward. Algae have other advantages over traditional biofuels because they can grow in salt water and thrive in harsh environmental conditions, thus reducing the pressure on food production and fresh water supply.
Algae oil can also potentially be processed in conventional refineries, producing a fuel no different from the convenient, energy-intensive diesel fuel. Oil derived from algae also promises to be a potential feedstock for the chemical industry.
Prospects and retrospectives of algal biofuels
Japanese carmaker Mazda Motor Corporation plans to use microalgae biofuels instead of regular gasoline and diesel. The automaker is currently supporting a number of research projects aimed at exploring the possibility of using biofuels.
Barring the global economic crisis, by 2030, 12% of aviation fuel will be produced from algae. Mexico expects to reach 1% within 4 years. The first algae biofuel vehicle was built in 2009. This biofuel – a liquid that resembles vegetable oil. The main problem remains money – the cost of production will have to be reduced by 90%.
Biofuel technology is very relevant and in demand the current development of civilization is an industry. Its significance lies not only in partial replacement of fossil fuels and reduction of greenhouse gas emissions gases into the Earth’s atmosphere, but also that its development will contribute to cleansing the Earth from the artifacts of human activity.