Thursday, 30 June 2011

on the algae trail - the most important plant in the world?

algae are important plants, are useful in the soil - some help fix nitrogen or make it bio-available, but of course one of the most interesting uses for algae would be in the production of biofuels.  We blogged here about algae being used in reactors (or living foundries) to create a biodiesel, for example.

So what is Algae?  Is it just seaweed?

want to know more?  here's a 50 minute in-depth seminar/presentation on algae:

but (if you survived that in-depth study) there are continuing developments in farming algae, reported just recently. Recall the algae bio-reactors?  Well in this news item here i spied a novel way of locating reactors with minimum land-use and greater efficiency of production - in bags at sea!

If you have been paying even the slightest attention to the algae industry, you probably have heard of companies like Solazyme or Synthetic Genomics, the big names that are making big public strides in the field. Algasol Renewables, on the other hand, is one name in the industry that you have probably never heard mentioned. However, Algasol looks to be on the brink of joining those big names as one of leaders in the algae industry with their photobioreactor system.

Photobioreactors (or PBR’s) come in many different shapes, sizes, and designs. Essentially, they consist of some clear material formed in a way that it can hold an algae-containing liquid. Typically, you will find them looking like long tubes, snaking back and forth, that allow sunlight to reach the algae-water concentration that is pumped through it. They work great for growing algae but have typically suffered from high initial and operating costs.

This is where Algasol comes into play. They have designed a photobioreactor system that can potentially cut costs by 90 percent. How have they done this? Well, their thinking has taken them outside the tube and placed them into a bag.

Basically, their system grows freshwater microalgae in large plastic bags that float on top of bodies of saltwater. There, as in any other bioreactor, nutrients and CO2 are pumped in to feed the algae.
This design led Frost & Sullivan to give Algasol their 2010 “Global Algae Biofuels Award.” According to them, “Algasol Renewables provides a critical and innovative method for micro algae biomass production. Its modular floating bag technology, a new variation of photobioreactors (PBRs), provides a low-cost design coupled with industrial scalability, optimal light exposure, high biomass concentration, low energy consumption, and efficient system control.”

The oceans of the world have a great potential to be the location for floating algae farms. First off, oceans cover around 70 percent of the world. With land (especially agricultural land) becoming a very precious commodity, moving production of fuel offshore is a major bonus.

Additionally, the ocean cuts out a lot of the energy costs associated with traditional PBR’s. For example, the water surrounding the bags acts as a temperature buffer, a process that would require spraying down the outsides of the photobioreactor in typical systems. Also, the wave action in the ocean helps to mix the algae in the bags, something that would otherwise take additional energy in land-based designs.

Now, some may be concerned about putting all this plastic into the ocean should a storm comes along or worried about what happens if these bags break. Luckily, engineers at Algasol have addressed both of these problems. If a storm comes along, the bags have been designed to be submerged beneath the water to levels up to 250 feet. There, they can wait out a tropical storm, hurricane, etc.

Researchers are also not too concerned if one of the bags breaks. Since the algae will be freshwater species, they will die when exposed to saltwater and there, researchers have concluded, they can become food for fish and other marine life.

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