Tuesday 18 October, 2011

Forget petrol & LPG, duckweed is here as the silverbullet

At a time when availability of petroleum, cost & environmental issues of various energy sources are haunting the mankind, duckweed comes as a great solution. Duckweed is the family of smallest flowering plants which are found floating on ponds and still waters all over the world. The capability of duckweeds, to multiply and double its mass in less than a day, is the promising factor that everyone is interested in. It grows better on waste water. Also duckweeds give many times more protein yield per hectare compared to other biomass/biofuel producing plants.

Duckweeds are being used
• As feed for cattle, poultry, fish, etc. Even humans eat duckweed in some places like Thailand.
• For cleaning grey water. Recovery of nutrients and treatment of municipal wastewaters done in India and other countries using duckweeds.

Advantages of using duckweed as energy source
• Can be used to generate methane gas or can be burned (Heating value comparable with coal).
• Very less transportation cost, if grown onsite.
• Zero pollution – pollutants during burning (directly or methane produced) are absorbed back during their growth.
• Can produce energy on demand (Don’t require expensive storage devices unlike renewable energy sources such as solar and wind energy).
• Very less energy required to ‘harvest’ duckweed compared to fast growing algae.
• Don’t require sophisticated technology to generate methane gas or electricity.
(Scientists foresee the future of renewable energy in bio-methane as it is equivalent to natural gas.)

• Edible crops like soybean and corn can be spared from using it for creating biofuel.

And finally Pacific Domes proves that it is practically possible.

Make electricity from duckweed“An Ashland company has teamed up with an East Coast engineer who has figured out how to generate cheap, clean electricity from a plant all too familiar to people who frequent the Lithia Park ponds — duckweed — and then use exhaust from the generator to grow more duckweed.
Pacific Domes of Ashland, a global marketer of geodesic domes, is now selling BioEnergy Domes developed by Rudy Behrens, an aerospace engineer whose patented system is capable of producing a megawatt of electricity for the same price as coal or nuclear energy — and significantly cheaper than wind or solar. The systems are green, sustainable, and can be either small enough for a single home or large enough for a municipal utility.”

If somebody can grow the energy source cheaper in the climatic conditions prevailing in the US, any takers for this in tropical countries where sunlight and climatic conditions are favourable for duckweed?