Algae have long been touted as a next-generation resource for manufacturing a whole range of essential products. However, the challenge is to grow and process them sustainably.
In one of the latest attempts to achieve this, the University of Greenwich, London, U.K., is leading a €10-million ($13.6-million) international project to develop the microalga Dunaliella as a sustainable raw material.
Dunaliella has been chosen because it produces a wide range of compounds appropriate for the project's biorefinery concept that aims to use every element of a biomass. It can cope with extreme conditions, from salt caves in the Antarctic to salt pans in the tropics. The high salinity and light intensity turn the microalgae orange by producing protective carotenoids, for which the alga already is used.
Overall, algae are known for their ability to convert carbon dioxide and sunlight into chemical energy five times faster than crops grown in soil. Dunaliella can produce up to 80% of its mass as fuel. Currently, cultivating the alga for fuel alone is too expensive, but it has the important added advantage of producing a range of compounds of great interest for pharmaceutical, cosmetic, nutraceutical and other applications.
"The race is on to develop a broader spectrum of compounds from algae which can be turned into high-value products including food and medicines. If we can make algae biorefineries commercially viable, we will have developed a new industry founded on an environmentally kind raw material which is also sustainable. The potential is huge," explains Patricia J. Harvey, who is project leader, professor of biochemistry and head of bioenergy research at Greenwich.
At the heart of the project's strategy is developing a biorefiney, called the "D-Factory," designed to turn every part of the alga into useful products. "By 2020 these algae may also provide us with sustainable fuel — the science is there, but at the moment the costs don't add up," notes Harvey.
The project brings together 13 research institutions and businesses from eight countries, including experts in the biochemistry of Dunaliella, large-scale cultivation of microalgae, novel harvesting technologies and bioprocessing development. Together they aim to set a world benchmark for a biorefinery based on microalgae. Plans include the largest commercial cultivation of the single-cell organisms — in water raceways, lakes and photobioreactors.
The project hopes to demonstrate the business case for global investment in algae biorefineries and large-scale production of microalgae. The group hopes to raise investment for the first prototype D-Factory in Europe within three years.
Based on prospects for the D-Factory, drug discovery company IOTA Pharmaceuticals, Cambridge, U.K., has chosen Greenwich as its academic partner to research the potential of the microalga Dunaliella as a route to new medicines.
"Over half of all human medicines originate from natural products," says Dr. David Bailey, CEO of IOTA Pharmaceuticals. "We are focusing on the proteins catalyzing these chemical transformations, using next-generation DNA sequencing approaches to identify, design and develop new processes for natural product synthesis."
Greenwich also is a key player in efforts to develop seaweed as a biofuel. The university is part of a 12-strong consortium of U.K. universities and companies that aims to develop manufacturing processes that can overcome two major challenges posed by seaweed: removing its high water content, and preserving it for year-round use.
Ensilage — a method traditionally used by farmers to turn grass into hay for winter animal feed — has potential to stop the seaweed from rotting. This research, backed by £1.6 million ($2.7 million) from the U.K.'s Engineering and Physical Sciences Research Council, also will explore the conversion of wet seaweed to gas, which can in turn be converted to liquid fuel.
Like Dunaliella, seaweed also is a microalga and capable of turning into chemical energy three times more efficiently than land plants.
"Current biofuels may not be sustainable," says Dr. John Milledge, research fellow in the school of science at Greenwich and an expert in the commercialization of algae. "First-generation fuels such as bioethanol from sugarcane and corn, or biodiesel from rapeseed and palm oil, are in direct competition with food for arable land and water. They have an adverse effect on food prices and supply. Salt-water algae are therefore a very attractive proposition as an alternative biofuel if we can overcome the challenges."
Milledge is working closely with Harvey to determine whether U.K.'s coasts can sustain large-scale biofuel production.
Seán Ottewell is Chemical Processing's Editor at Large. You can e-mail him at firstname.lastname@example.org