Utilize Carbon Capture Technology Effectively to Tackle Global Warming

Interest in technology to capture and bury underground carbon dioxide emitted from thermal power plants and other sources is growing worldwide as part of decarbonization efforts. Japan must also swiftly put the technology into practical use.

Called carbon dioxide capture and storage (CCS), the technology involves separating and capturing CO2 from exhaust gases emitted from such facilities as power plants and factories, using materials such as special membranes and aqueous solutions.

The collected CO2 is then transported by ship or pipeline to a storage site, where it is injected into a geological layer at a depth of about 1 to 3 kilometers. After being compressed, it is stored in hard geological formations deep underground to prevent CO2 leakage.

Japan is increasing the use of renewable energy sources such as solar power in an effort to reduce CO2 emissions, but the lack of suitable sites makes rapid expansion difficult. For the time being, the country has no choice but to rely on thermal power generation using natural gas and coal.

With the spread of CCS, it will become easier to continue thermal power generation. There are other industries, such as iron and steel, where CO2 emissions are difficult to reduce, so it can be said that the benefits of the technology will be significant for these industries.

In Japan, domestic companies in the petroleum, electric power and trading sectors, among others, are planning to commercialize the technology. In June, the Economy, Trade and Industry Ministry announced that it will focus support on projects at seven locations in Japan and abroad, including sites off the coast of Kyushu, along the coast of Hokkaido and in the Tokyo metropolitan area. The government intends to subsidize costs for surveying geological layers, among other efforts that will lead to practical applications of the technology.

The ministry expects the projects at the seven locations to be able to store about 13 million tons of CO2 in fiscal 2030, equivalent to slightly more than 1% of Japan’s annual CO2 emissions.

According to one estimate, an annual storage capacity of 120 million to 240 million tons of CO2 will be necessary to achieve the nation’s goal of virtually zero emissions by 2050. The government plans to increase the number of domestic storage sites to 20 to 25 by 2050.

However, according to the ministry, the initial costs are expected to be several tens of billions of yen, and it will cost at least about ¥10,000 per ton from collection to storage. Lowering costs is essential. The hope is that the public and private sectors will cooperate in developing technologies to bring costs down.

It is also important to gain understanding from local residents and fishers near planned storage sites. The ministry has already conducted a feasibility test off the coast of Hokkaido and succeeded in storing 300,000 tons of CO2 by 2019. The ministry said there was no leakage, even after earthquakes.

In addition to carefully explaining the significance of CCS and the process, the government must make it mandatory for operators to implement thorough safety measures to alleviate the concerns of local residents and others.

Overseas, the U.S. government announced in May a new regulatory proposal that would require thermal power plants and other facilities to use CCS. There are about 150 CCS projects worldwide, including in the United States, Europe and China, with 30 already in operation.

The Japanese government and business operators should also strengthen cooperation with the United States and Europe, which are ahead in the field of CCS.

(From The Yomiuri Shimbun, June 23, 2023)