The breakthrough idea came after two years of work. Sea6 Energy
founders were convinced till then that microalgae held the secrets to a clean
energy future. So did thousands of other entrepreneurs, researchers and
investors around the world.
Algae could produce many times more oil per unit area than any plant in
the world. But two years into the project, and some serious calculations
later, four students and their professor at IIT Madras were convinced that
microalgae economics just wouldn't work for some time.
Renewable energy isn't anyway economical at the moment without subsidies,
but algal biofuels seemed hopelessly uneconomical. It was then that they
thought of macroalgae.
Macroalgae is a technical term for seaweed. It seemed an extremely
attractive proposition as an oil source even at first look. Seaweed grows in
the shallow ocean waters and doesn't need land.
Technology for its cultivation is well-established: it is being grown in
the Tamil Nadu coast as a raw material for some cosmetics. Seaweed does not
need external nutrients for growth: the sea is the ultimate nutrient
reservoir. It grows quickly, is cheap and easy to harvest.
Microalgae on the other hand needed fresh water, large nutrient inputs
and plenty of land. "We were preparing to abandon the project when we realised
that we were chasing the wrong idea," says Sea6 Energy chairman Shrikumar
Suryanarayan. Suryanarayan was for two decades the head of R&D at Biocon.
He had left his job there in 2008 and was teaching at IIT Madras when
some students sought his help to enter the prestigious iGEM competition at the
Massachusetts Institute of Technology (MIT) in the US. They were denied a visa
but still won a prize after making a video presentation.
Shrikumar then got them interested in biofuels. "We went to algal biofuel
conferences and realised that we were at the same level as others," says
Sayash Kumar, one of the students. Two years later, when they had finished
their master's degree and were beginning to disperse, somebody thought of
seaweed.
Only three other organisations then worked on macroalgal biofuel: Bio
Architecture Labs based in San Francisco, the Korean Institute of Industrial
Technology and the Philippines government. The microalgal biofuels landscape
was littered with startups, but with no commercial breakthrough in sight, many
of them were no longer able to raise money. Yet the sector has seen some of
the biggest investments in renewable energy.
Silicon Valley-based Synthetic Genomics got $300 million from
ExxonMobil, and San Diego-based Sapphire Energy has so far raised $100
million. Pike Research has predicted the global biofuels market to reach $247
billion by the year 2020. It was a good business in the long term.
Sea6 Energy was formed in July 2010. Shrikumar and a few IIT alumni
chipped in with about Rs 1 crore to get the company going. Their first
challenge was to tackle the seaweed cultivation itself. Pepsi had got together
people in coastal Tamil Nadu to cultivate seaweed for its food products. The
price of seaweed is now Rs 20 a kilogram. To be viable as a biofuel input, its price
has to come down to Rs 5 a kilogram.
Since the entire cost of cultivation was in labour, mechanisation was the
only way to bring it down. Farmers cultivate seaweed on floating bamboo rafts
in calm waters. Biofuel demands its cultivation on a very large scale, and in
rough waters around most of the country's shores.
So the first job of Sea6 Energy was to create a strong framework to
anchor the seaweed, which is heavier than water and sinks to the sea bottom.
It was not a trivial problem but not impossible either.
The sea is a hostile environment but marine engineers had been working
with several good materials. Sea6 realised that bamboo rafts break because
they were rigid structures. A mesh structure that can move at the vertices
would absorb the stress quite easily.
The company developed an offshore farming system, based on a marine
plastics polymer, within six months of incorporation. It has also filed a
provisional patent application. The founders are tackling the next steps, of
finding a biological method to break down the plant into sugars and then
converting the sugars into alcohol.
Unlike plants, seaweed contains no lignin and is easier to break down.
Sea6 needs a microorganism that works in sea water. It has found a few.
Converting the sugars into alcohol or other fuels is the easiest task. "Once
you have sugars," says KB Ramachandran, professor of biotechnology at IIT
Madras, who is incubating the company now, "we can make any petrochemical
product."
Microalgae work a bit differently as they produce oil directly. When
compared to plants and microalgae, the economics and technology are loaded
heavily in favour of seaweed. Sugarcane has the highest productivity among
plants, but you can get only 30 tonnes of it in a hectare. A similar area can
produce 100 tonnes of seaweed. Simple calculations will show that you need an
area roughly the size of Punjab to produce all the oil that the country needs
using seaweed.
"At the moment, from a technology point of view, seaweed is superior to
microalgae," says Syed Yazdani, synthetic biologist and scientist at the
International Centre for Genetic Engineering and Biotechnology (ICGEB) at
Delhi. Sea6 Energy would need Rs 50-60 crore over the next four years to
develop a farm of one sq kilogram with a demonstration plant that produces ethanol
and other petrochemical products.
By then the rest of the world would have also made substantial progress,
judging from the increasing interest on seaweed. By then we should know
whether large-scale seaweed cultivation brings up unforeseen environmental
problems.
