The first slide shows the history and the future prediction of worldly oil production. It is generally believed that worldly oil production will peak in less than 10 years. As you can see from the figure, USA and Russia passed their oil production peaks decades ago, in 1970s and 1990s respectively.
After world oil production peaks and declines, the world will face a severe situation. The situation is that the world simply cannot produce enough fossil oil to meet the demand from transportation.
This oil gap for transportation has to be filled. Biofuels are one of the candidates to fill this oil gap. Biofuels are derived from biomass. And biomass used for producing biofuels can be grains, hay, weeds, woods and others.
The first generation biofuels derived from crops. For example, in USA, corns are used for producing ethanol; in Brazil sugarcane are used for producing ethanol; and soybeans are widely used for producing biodiesel. But corn, sugarcane and soybean are crops. The main problem facing crop-derived biofuels is conflict between food production and biofuels production. Other problems concerning crop-based biofuels production include deforestation, high production cost and limited potential. Take the limited potential for example: Even if all the corn currently produced in the USA were used for producing ethanol, it could only replace about 15% of oil currently consumed in the USA.
Microalgae are single-celled lower plants that make seas, lakes and rivers green. When you walk around a natural pond in the spring and summer, you can find the surface of water is covered by green stuff. That are microalgae. Microalgae are "plants" because they can grow by using sunlight, CO2 and water.
There are several advantages of using micro-algae for biofuels production over crops.
First, microalgae grow much faster than land plants. It can grow 7 to 30 times faster than the next best crop. Under the optimum conditions, microalgae can double its biomass in several hours.
Second, cultivation of microalgae doesn’t compete for farmland. Algae can be grown on land that is not suitable for crops, for instance, arid land, land with excessively saline soil, and drought-stricken land. Moreover, 70.8% of the earth’s surface is cover by water. Microalgae can be cultivated in open ponds, and even in the sea.
Third, algae-based biofuels are CO2 neutral, which does not deteriorate Global Warming effect. Algae absorbs CO2 from atmospheres when it grows and the CO2 is released back into atmospheres when the biofuels is used.
Fourth, microalgae can be harvested daily or any time needed, not like crops that are limited by their long growth cycle.
The main challenges facing algae-based biofuels are lack of cost-effective technologies to cultivate, harvest microalgae and to process microalgae into biofuels. But this is not strange. Human Beings have been planting crops, such as corn, sugarcane and soybean, for at least five thousand years, but cultivating and processing microalgae for biofuels is still in experimental stage. There is a lot of space to develop an improve algal cultivation, harvesting and processing technologies.
Utilizing microalgae for biofuels production will bring many benefits to the society and the country, such as breaking the USA’s dependence on foreign oil, creating a new source of green energy and adding job opportunities.
Microalgae are one of the most promising sources for biofuels production. But to make it reality, renovation of technology in this area is needed. And to renovate the technology, more money and more human resources should be invested.
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The above is one of 8 - 10 min speeches I delivered in my Toastmasters club. The speech is based on AC#2: The Proposal.
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