American scientists, working in the framework of the project OMEGA, were able to establish the mass cultivation of algae on wastewater to obtaining from them biofuels. According to one of the participants, it is very similar to "Neolithic revolution" in the energy sector: from "hunting and gathering" energy people are gradually moving to their cultivation.

Why would "green" replace oil for biofuels, while this idea seems completely unreasonable from the economic point of view. Here's a simple example - the major plants, of which now have the biodiesel rapeseed and soybeans, give a year more than 20 billion gallons of fuel. But it all turns around for agriculture? In huge losses of acreage under plants giving food.

As of 2010, the area given over to "biodiesel" rape has already amounted to 15 million hectares. But this is the most efficient fuel and culture, if the whole world biodiesel made from soybeans, from food turnover would bring 40 million ha of land. This is not to say that all these sacrifices helped biofuels to replace oil.

According to calculations in the same year 2010, the whole world "burned" then about 4.8 trillion liters "black gold", that is, in a quarter of thousands of times more than was produced biodiesel. It is easy to calculate that the alleged replacement even 40% of oil at such biofuels would lead to the withdrawal of food millions't even hectares and square kilometres of farmland. Given the looming food crisis!

So while the transition to biofuel keeps one simple rule, which can be formulated as follows: "or food or fuel". It is not surprising that from this couple humanity still chooses first. However, according to some data, sugar cane is more effective producer "green" fuel than rape, but the trouble is that natural area, where it can normally grow very, very small.

However, claim the experts of the Research center Ames (California, USA), alternative after all. And this is microalgae (among which the most popular is known to all single-celled particular Chlorella), a large group of single-celled, which differ from higher plants not only ultra-fast reproduction, but also the fact that in their cells contains up to 70% natural oils. It is from them that using interesterification can easily get the desired biodiesel, and pressing calmly be fed to livestock (because it is very rich in protein). And, most interestingly, the fuel of Chlorella is quite high-quality - tractor at least working on it quite normal.

Scientists say that if higher terrestrial plants productivity by oil, that is the source of raw material for biodiesel, rarely exceeding 1 000 l/ha, the algae will give the same oil in volume of 18 700 to 95 000 liters per hectare of water surface. By the way, the benefits are still here because the Chlorella growth needs water, not the soil. And it's guaranteed to exclude competition from ood" crop acreage - in fact in the water then they do not grow.

However, these water hectares also need somewhere to get it. For example, if in the coming years in the USA, as is planned, will begin to consume 80 billion liters of biodiesel a year, for its production will require "SMB" algae area of 43 thousand km2. To replace half used by mankind oil will need space 30 times. But where to take as much freshwater - if to consider, that now the rapid growth of the population each ml of drinking water on the account.

There is another problem - all microalgae have a bad habit to fill the entire exposed surface of the water body and cause "flowering" of water. The consequences are devastating for all other inhabitants of the given area - cell algae withdraw from the water all the oxygen and, moreover, block the receipt from the air, catching valuable gas on the way. All this creates a phenomenon which is colloquially called "Zamora", in which all the inhabitants of reservoirs suffocate to death, and their bodies develop anaerobic bacteria, toxic water hydrogen sulfide, which eventually kills themselves perpetrators "Zamora".

However, the American biotechnologists believe that all this can be avoided, if we grow the algae in the ocean. However, no open water (but then so is the ocean "be" not for long), and in special containers. Specialists managed Jonathan Trent from Oceanographic SCRIPPS institution of Oceanography at UC San Diego have developed a special transparent plastic tube, sealed at both ends. They are free to swim in the ocean not far from major cities, where it is believed, is home to 40% of the world's population, in the offshore waters, large bays or at least behind the line of artificial breakwaters.

But what is most interesting is that in these pipes-bioreactors will be injected fresh sewage, which will grow Chlorella. And as with them, no problems should not be - according to the UN now their volume is 1 500 km3 per year, with 80% of this stinking liquid generally does not cleaned, and cleaned the remaining 20% goes from 2 to 3% of the electricity produced in developed countries. Chlorella and her relatives can make these clean water for several days, deleting all of them are necessary for vital activity of algae organic.

As you can see, this project promises a double benefit - and clean water will become more and biofuels can be reserved. By the way, deleting already purified water must pass through the plastic walls made of semi-permeable membranes that are not manufactured only by algae and organic molecules and everything else through them freely comes out. And if such a wall will damage the storm, who spilled the contents of the bioreactor will not be able to damage to marine ecosystems as freshwater algae will just die in salt water.

It should be noted, that now such photobioreactors, created in the framework of the project OMEGA, who oversees NASA, already tested in San Francisco. Interestingly, they are processed and associated technologies - for example, the combination of growing "biodiesel" algae cultivation of mussels. Scientists have already created on the surface of the Gulf experienced "field" for sewage treatment area in a half hectares - and the results are very encouraging. According to Jonathan Trent, it is very similar event "Neolithic revolution", but in the energy sector: from pumping oil and gas, that is "hunting and gathering" people can go to the cultivation of liquid fuel, and the cost of energy supply will be less.

However, even if such technology and prove their profitability, alas, not all countries will be able to use it. Cheap biodiesel can get only those States that are near the warm seas - the USA, Australia, countries of Africa and Latin America, Southeast Asia, etc., But Russia, with its tamerselim waters probably have to find another way biofuel production at reasonable prices...