As Japan’s rice fields turn fallow and its farming communities decline, a new army of workers is preparing to make the countryside fertile again. This time the crop is motor fuel and the laborers are microscopic algae.

At least 75 developers globally are studying algae, which has the potential to generate more energy per hectare than any other crop used for making fuel, according to Bloomberg New Energy Finance. The technology has attracted the U.S. Department of Energy and big oil including Exxon Mobil Corp., which plans to spend as much as $600 million on research over five years.
Japan abandoned a $132 million algae project in the 1990s, when oil prices dropped below $10 a barrel and climate change took a back seat to reviving the economy in what became known as “the Lost Decade.” Now companies including Toyota Motor Corp. and refiner Idemitsu Kosan Co. may join a study into the microorganisms that can turn waste water into oil, scrub carbon dioxide out of the air and reduce dependence on fossil fuels.
“It could be a kind of alchemy,” said Makoto Watanabe, an environmental science professor at Tsukuba University, which has invited the companies to join the study. “It has enormous potential to become one of our major energy sources.”
Microalgae use sunlight, water and carbon dioxide to produce oxygen and biofuel through photosynthesis. The plants, which look like a green film on the surface of water, can be cultivated on marginal land in open ponds or in “photobioreactors,” incubators that protect them from contamination and maintain a steady temperature for more intensive production.
Emissions from factories and power plants can be pumped into the reactors. That makes algae an alternative to carbon- capture and storage projects, which inject carbon dioxide into underground rock formations, according to a New Energy Finance report. Carbon dioxide, one of the greenhouse gases blamed for global warming, makes algae grow faster.
Algae are more productive than crops because they keep making fuel regardless of the weather, according to the research group. All the transport fuel needs of the U.S. could in theory be met by algae cultivated in an area the size of Belgium, it said.
Algae is among “second-generation” biofuels, designed to overcome the disadvantages of fuels from food grains. Riots broke out in cities from Cairo to Jakarta in 2008 after food prices soared, fueling widespread perceptions that U.S. subsidies were encouraging farmers to plant crops to make ethanol for American cars while the world’s poor starved.
Researchers are now pursuing agricultural waste, fungus and other fuel sources that don’t compete with food crops.
The Botryococcus algae being studied by Tsukuba University produces fuel that’s almost identical to diesel, said Watanabe, who is leading the project. Watanabe said he met a production target of 1,000 metric tons per hectare a year in a laboratory experiment.
Costs are about 800 yen a liter, compared with gasoline, which retails for about 130 yen in Tokyo, Watanabe said. He estimates he can reduce costs sufficiently by 2022 to compete with ordinary oil products.
“The challenge is to create an environment for the algae to grow fast and produce a significant amount of oil,” he said.
Academics have projected algae fuel could fall to as low as $2 to $4 a liter, according to the New Energy Finance report. That compares with surgarcane ethanol, usually the cheapest biofuel, which costs between 20 cents and 45 cents.
Algae fuels are still a long way from replacing fossil fuels, said Robert Rapier, chief technology officer for Merica International, a bioenergy holding company.
(Source: Bloomberg)