Japan’s ‘clean coal’ power experiment is starting to bear fruit

Japan is winding down a project aimed at using technology to make the burning of coal to generate power less environmentally damaging.

On a small island in western Japan’s Hiroshima prefecture, reachable only by a 30-minute ferry ride from the mainland, a decadelong attempt to prove coal can be made “clean” is drawing to an end — though its accomplishments face a murky future. A 118,000-square-meter jungle of tanks, chimneys and pipes spreads out against the sparkling Seto Inland Sea and green mountains. Visitors are largely prohibited from taking photos for fear of leaking Japan’s front-line technologies. The project is aimed at making burning coal, a major source of energy for resource-poor Japan, less environmentally damaging. The site is backed by 49 billion yen ($384 million) of public funding. But much of the world now wants coal use to be reduced to avoid climate damage.

“I’m deeply moved that our years’ worth of efforts are starting to take shape,” said Tetsuo Kikuchi, president of the project’s manager Osaki CoolGen, a joint venture established in 2009 between utilities Electric Power Development, commonly known as J-Power, and Chugoku Electric Power.

The three-stage project in the town of Osakikamijima, scheduled to conclude by March, produces coal power “drastically differently” from past ways, he told Nikkei Asia.

In the first stage, researchers developed technology to lessen the amount of coal used. Conventional plants generate power by burning coal and producing steam to spin a turbine. The Osaki plant tested spinning one by heating the coal while blowing oxygen on it to produce gas. That enabled about 15% higher efficiency, meaning coal used and carbon dioxide emitted would decrease by the same rate.
Such technology has also been tested in China, South Korea and the U.S., but with little practical success. Osaki researchers achieved a level sufficient for commercial use, Kikuchi said, declining to disclose details.

Nevertheless, the company says a plant using the technology alone would still emit almost twice the amount of carbon dioxide compared with a liquefied natural gas one. So it added a carbon capture facility in the second stage to further cut emissions. Testing confirmed they could be lowered another 90% by using a relatively cheaper method of carbon capture technology, thus also increasing commercial viability.

The company also found that gasifying coal produces not just CO2 as a byproduct but also hydrogen. The test plant added a fuel cell battery in the third stage to use the hydrogen to produce more power.

“A coal plant with low emissions and [that] even makes hydrogen, an energy source that is rapidly gaining attention today — this can completely alter the notion of coal,” Kikuchi said.

Osaki has attracted visitors from the government in Australia, a major coal exporter, and Asian countries that are also exporters or heavy users of coal, Kikuchi said. Japan, which sources about one-third of its power from coal, sees the project as key to its policy of safely achieving energy security as well as economic and environmental efficiency. Coal is “an important energy source with excellent stability of supply and economic efficiency at present, because it has the lowest geopolitical risk related to procurement, is cheap and is easy to store,” said the nation’s latest energy plan in 2021.

Hopes for the fuel grew after 2011, said Kentaro Tamura, head researcher for the climate and energy unit at Japan’s Institute for Global Environmental Strategies. The then-government’s hopes that nuclear power would help decarbonize the power sector “fell apart” after the Fukushima nuclear disaster, while the economy was burdened with high natural gas prices. “The notion that coal-fired power was the way to go came to be deep-seated in the [Japanese] industrial world,” Tamura said. That feeling has remained, even as renewables took off worldwide in the 2010s as more countries acknowledged the urgency of the climate crisis.

In 2020, Japan committed to phasing out inefficient plants toward 2030, but did not join over 40 countries in signing a treaty in 2021 to exit coal power. Its energy plan still includes an expectation that coal will remain a “regulating power source” supplementing renewables.

Technologies to make coal cleaner will “contribute to Japan’s climate targets” of cutting carbon dioxide emissions by 46% by 2030 from 2013 levels and reaching net zero by 2050, said an official in the coal department of the Ministry of Economy, Trade and Industry. Japan has hinted at wanting to export “clean” coal technologies to developing countries in Asia, which have young coal plants and are expected to face difficulty phasing them out. But questions remain, including whether such coal power will be competitive against renewables and other eco-friendly energy sources, not to mention if its use will benefit decarbonization.

Currently, there is one plan to use the findings through the second stage of the Osaki project at J-Power’s 42-year-old coal plant in southern Japan’s Nagasaki prefecture. Commercial operation is set for 2026, by which time it expects the business environment for carbon capture, storage and utilization (CCUS) — an expensive endeavor not yet in wide use — will also be ready.

But Japan has set a 2030 target for operationalizing carbon storage and faces numerous hurdles, from developing legislation to subsidies.

“I hope the government will work quickly to establish a system and work out regulations that would enable carbon storage for Japan,” Kikuchi said.

For Southeast Asia, Japan’s target region for coal technologies, additional investment in coal power hinges on the region’s own energy security needs amid pressure to invest in more widely acknowledged clean technologies like renewables. Japan, meanwhile, has struggled to scale up renewables like offshore wind power. It has also been slow to embrace carbon pricing — a key for renewables to take off — due to industry reluctance.

Prime Minister Fumio Kishida hails from Hiroshima prefecture, where the project is taking place. Hiroshima will also be the venue for the annual Group of Seven summit of advanced economies in May. Kishida is likely to promote the experiment as a Japanese-style carbon-neutral model technology, while expectations are also high for it as a growth strategy for the country through its export to Southeast Asia.

But Tamura of IGES expects Japan to face increasing pressure to strengthen climate commitments, including on coal, especially as chair of the G-7 this year. The nation is out of step with the group on coal.

“Other members of the grouping are deeply concerned that current codes to reduce emissions are not enough, and will want to send strong messages to the world to speed this up,” Tamura said. “Whether Japan can lead that discussion is unclear, and negotiations could be rough.”