By Dr Vandana Prakash
ECO Worldly
April 23, 2009
The algae! Yes – the same slimy brown-green ‘plant’ that makes a pond or a lake look yucky – is the creating a great buzz as the most promising source of alternative energy. And now nanotechnology is being leveraged to add some more zing to the promise!
Algae are some of the simplest of the living organisms and can’t even be classified as plants as they lack any differentiation into various structures such as leaves, roots or other organs that characterize a plant. Yet this simple structure is the very reason for the alarming growth rate of the algae: Under optimal conditions, it can double its mass overnight.
One interesting aspect of the bio-fuel generation from algae is other side benefits such as carbon mitigation; the algae consumes carbon-dioxide (CO2) to grow, besides water and sunlight. What also adds to the potential is the fact that oil forms up to 50% of the algae’s mass. Compare this with palm-oil trees having at most 20% of their mass as oil. Furthermore, it is not only the algae-oil that can be used for bio-diesel generation but algae-carbohydrates can also be fermented into ethanol or gasified into bio-gas, or into methane, or into hydrogen. Indeed, the time is ripe for doing more than simple pilots for bio-fuel generation from algae. The Venice example, discussed on Ecoworldly earlier, is one such recent initiative that demonstrates co-operation and building of complete infrastructure for bio-reactors and CO2 provisioning etc. India too has another example to offer of going beyond simple pilots.
But as is the case with upcoming technologies they take time (or gestation lags) to mature before becoming commercially viable. Especially true for achieving the full projected potential of generating greater than 5000 gallons per acre per year of algae-bio-fuel as opposed to a (seemingly) measly 50 gallons per year per acre from Soy. Algae bio-fuel has become a hot topic: And there have been several summits and conferences {For example, in San Francisco(USA), Delhi(India), etc.} to discuss potentials and pitfalls. Here is a very well written article that succinctly attempts to separate the hope from hype in using algae for bio-fuel generation. Since algae-farming also demands water, there is natural anxiety about re-incarnating the food versus fuel battle in case of ethanol generation into a water versus fuel battle for algae-driven bio-fuel generation. Another hurdle in realizing the full potential of algae bio-fuel is the fact that the ambient concentrations of C02 in atmosphere are not enough for the exponential growth of algae.
Recently two interesting pilot programs to improve the commercial viability of algae bio-fuel caught my attention. Both of these pilot programs utilize the benefits of yet another technology with ‘great potential’: nanotechnology. Nanotechnology is the discipline of building machines/devices on the scale of molecules, a few nanometers wide, way smaller than a cell.
The first was the grant from the California Energy Commission to use the nano-metals as catalysts for generating bio-fuel from algae. The company called QuantumSphere will be developing a nanocatalyst-based bio-gasification process for taking wet algae from Salton Sea in California. Salton Sea is one of the largest and lowest inland seas at 227-feet below sea-level. According to the QuantumSphere technologists, Salton Sea has good algae growth, driven by large agricultural runoff. The 12 month project will build a small plant on the shores of Salton Sea to demonstrate effectiveness of algae bio-fuel generation. Besides exploring the commercial viability of the algae as source of alternative energy, this project is expected to help reduce the gap between the opposing positions about whether Salton Sea is a “cesspool of sewage and pollutants” or a clean and safe habitat as “California’s crown jewel of avian biodiversity”.
The second project leverages the nano-particles as harvesters for collecting oil from algae – without harming the algae crop!The process developed by the Ames Laboratory and Iowa University does not harm the algae like the current methods do. Thus, it reduces both the production cost as well as the generation cycle. Concerns are already rife about the safety of the nano-harvesters in case they get released into the environment. The particles themselves are considered environmentally safe as they are made of calcium and sand. Surely, the technologists and the regulators will observe due-diligence in ensuring the safety of these processes.
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