Algae fuel : Next Generation Biofuel

Biodiesel is usually made by combining methanol and lye with vegetable oil, animal fat, or recycled cooking grease. It can be blended with ordinary diesel to reduce vehicle emissions or used in its pure form. And it can even be transformed into a kerosene-like jet fuel. Unfortunately, the world doesn't currently have enough vegetable oil or old grease to make sizable quantities of biodiesel. Even if the United States were to devote its entire annual crop of soybeans to producing biodiesel, it would barely make a dent. But no nation would ever do that, because food production is still the No. 1 use for soybean oil. Algae, on the other hand, need not present such a conflict.

Algae fuel might be an alternative to fossil fuel and uses algae as its source of natural deposits. Several companies and government agencies are funding efforts to reduce capital and operating costs and make algae fuel production commercially viable. Harvested algae, like fossil fuel, release CO₂ when burnt but unlike fossil fuel the CO₂ is taken out of the atmosphere by the growing algae.

Algae are tiny biological factories that use photosynthesis to transform carbon dioxide and sunlight into energy so efficiently that they can double their weight several times a day.

As part of the photosynthesis process algae produce oil and can generate 15 times more oil per acre than other plants used for biofuels, such as corn and switch grass. Algae can grow in salt water, freshwater or even contaminated water, at sea or in ponds, and on land not suitable for food production.

On top of those advantages, algae — at least in theory — should grow even better when fed extra carbon dioxide (the main greenhouse gas) and organic material like sewage. If so, algae could produce biofuel while cleaning up other problems.

Algae cultivation

Algae can produce up to 300 times more oil per acre than conventional crops, such as rapeseed, palms, soybeans, or jatropha. As algae have a harvesting cycle of 1–10 days, it permits several harvests in a very short time frame, a differing strategy to yearly crops (Chisti 2007). Algae can also be grown on land that is not suitable for other established crops, for instance, arid land, land with excessively saline soil, and drought-stricken land. This minimizes the issue of taking away pieces of land from the cultivation of food crops (Schenk et al. 2008). Algae can grow 20 to 30 times faster than food crops.

Oil Production from Algae in Four Steps:

1.Pick a Strain

Algae naturally produce oil as a way to store chemical energy. Companies begin by selecting from more than 60,000 strains and then growing the algae. Some strains are more productive or efficient; others thrive better in different regions or climates. Another option is to splice and breed new varieties.

 2.Grow the Algae

Small amounts of algae are then put into a tank with water and nutrients similar to those in household fertilizer. Typically the algae are now exposed to sunlight, whereupon it rapidly reproduces and undergoes photosynthesis, converting carbon dioxide into sugar. The cell then metabolizes the sugar into lipids, or oil. The cell's cavity fills with as much as 60 percent of its weight in oil.

3.Extract the Oil

 Some companies press the algae like olives, physically squeezing the oil out. Others apply compressed carbon dioxide, which vaporizes the lipids until the pressure is lowered and the oil re-condenses away from the remaining cell. Other methods include solvents that remove the lipids, or sonic waves that burst the algae and cause the oil to spill out. The remaining parts of the algae cells can be used in other products, including animal feed.

4.Refine

A catalyst removes oxygen from the oil and replaces it with hydrogen molecules, making diesel fuel. Though more expensive, by altering the length of carbon chains, refiners can also convert the algae oil into gasoline and jet fuel.

Biofuels of the first generation are those produced from food as raw materials, whereas the second generation biofuels are those produced from inedible woody biomass such as grasses, waste woods and some kinds of algae. Generation-1 biofuels were strongly criticized that they caused a significant increase of food prices. Consequently, research and development races for Generation-2 biofuels are more and more accelerated.

Biofuel: Advantages

The use of algae for biofuels has received attention recently as a promising source of biofuel oils, in contrast with the high prices of traditional sources. It has been shown to require 1/100th of the water per acre compared to other crops, and the carbohydrate and protein elements can be used for other purposes including feed and fertilizer. It is low maintenance and its ability to ingest carbon dioxide and excrete oxygen is attractive because it reduces carbon emissions.

Drawbacks

A new study suggests that while algae might produce good fuel, the environmental costs involved in the production would be heavy. A life-cycle assessment published in the journal Environmental Science and Technology argues that algae production consumes more water and energy than other biofuel sources like corn, canola, and switch grass, and also has higher greenhouse gas emissions.

While the study’s results are sobering, they’re also being met with harsh criticism from algae-based biofuel companies and their trade group, the Algal Biomass Association.

Possibilities in Bangladesh and other south Asian countries

Here in Bangladesh, power sector is dying for energy sources. Using sugarcane and other crops we could not possibly produce the ultimate production of required energy that we need. However, second generation of biofuel makes it easier for us to consider the substitute energy factor of fossil fuel.

Recently, Algae.Tec closed a deal with Holcim Lanka Limited to build its first algae biofuels production facility in Asia that will reduce carbon dioxide emissions from cement manufacturing.

World Health Energy Holdings, Inc. (WHEN) has announced the signing of Letter of Intent (LOI) with Prime Inc., an India Industrial and transport Company, to develop a biodiesel production facility ramping up to 250 acres with a budget of up to $ 100 million.

The proposed sites for development are in Tamil Nadu and Karnataka in India. The project will employ an Algae Enhancement Technology, known as the GB3000 system, for growing algae for the production of fish feed, proteins and bio-fuel in India. Prime Inc. India’s current clients include Exxon, Shell, General Electric (GE) and Siemens.

Conclusion:

Most people consider algae a nuisance. But it turns out that one man's pond scum is another man's gold, to draw on an old expression. An algal species with the right properties could be immensely valuable.  Like ours, many third world developing countries are suffering for energy crisis, especially in recent decades, when the whole world is searching for alternative source of energy. Algae fuel can be a solution? Can be, but we have to wait and see what is coming from the researchers in the next few years. 

(Collected and Moderated)

এই লেখার সর্বস্বত্ব লেখকের ।এই লেখা লেখকের অনুমতি ব্যাতীত প্রকাশ,মুদ্রণ,অনুলিখন কিংবা কোন রচনায় প্রকাশ করিলে লেখক আইনানুগ ব্যাবস্থা নিতে বাধিত হইবেন।লেখকের মৃত্যুর পর লেখাগুলির সর্বস্বত্ব লেখকের পরিবারের।