Emerging Technologies Bid Hope for Clean Power Generation

Many researches are going on around the globe to further improve the process of clean power generation. Some of them are producing quite satisfactory results too. This article is to provide information on two such recent developments… - P. K. Chatterjee (PK)

There is no need to state that the demand of electricity will continue to scale up with the growth of world population. However, at present, we are facing a big challenge to mitigate further deterioration of the global climate. Fossil fuel use is the primary source of CO2. Thus, many steps are being taken around the globe to stop the traditional use of fossil fuels.

We all know that the renewable energy sources are the only alternatives. Still global renewable generation capacity at the end of 2022 was only 3, 372 GW (Source: IRENA). In the first half of 2022, total global electricity demand reached 13,393 TWh. Thus, we have to increase the use of renewables and continue to develop the field through R&D.  Today, here I will present two such promising initiatives.

A joint research agreement

Electric Power Development Co., Ltd. (J-POWER), Tokyo Electric Power Company Holdings, Inc. (TEPCO HD), Chubu Electric Power Co., Inc. (Chubu Electric), Kawasaki Kisen Kaisha, Ltd. (K LINE), and Albatross Technology Inc. (Albatross), have entered into a joint research agreement for a next-generation (floating axis) offshore wind turbine demonstration project.

The Japanese government has announced the intention to maximize the adoption of renewable energy sources as part of the nation’s commitment to achieving carbon neutrality by 2050. There offshore wind power, in particular, is considered a vital part of the initiative to make renewables a primary source of power due to the potential for large-scale installation, lower cost, and economic ripple effects. In Japan, with limited shallow sea areas, there is growing interest in floating offshore wind power because it can be deployed in deep water. To promote the widespread adoption, it is essential to significantly reduce costs through technological development. In addition, increasing the ratio of domestic production (in Japan) is expected to create a strong economic ripple effect.

Against this backdrop, the five partnering companies in this demonstration project will jointly develop a small-scale (20kW) next-generation experimental floating axis wind turbine that is expected to reduce costs and increase the domestic production ratio.

The floating axis wind turbine (FAWT) is a concept under which a vertical-axis wind turbine is supported by a ‘rotating’ cylindrical floating foundation. Its main features are as follows:

The wind turbine can be tilted 20 degrees at
maximum output, as it is designed to maintain effectiveness even when tilted. This allows for downsizing for the floating foundation and a significant reduction
in equipment costs.

The wind turbine section can be manufactured at low cost through continuous pultrusion moulding process used to form composite materials into long shapes, with carbon fibre reinforced plastics (CFRP).

By taking advantage of the characteristics to install vertical axis wind turbines close to sea level due to their specific characteristics, operation and maintenance costs for the major apparatus are also anticipated to be substantially lower.

The wind turbine blades can be manufactured in lengthwise sections with the same cross-sectional shape, eliminating the need for large-scale manufacturing facilities. Additionally, this design makes sections easier to transport, and is therefore suited for domestic production.

Japanese companies hold approximately 80% of the market share for carbon fibre, the raw material used in the carbon composite for the wind turbine.

Artist’s concept of a floating axis wind turbine (FAWT) wind farm…
Image Courtesy: Albatross Technology Inc.

J-POWER, Osaka University’s Graduate School of Engineering and Albatross are jointly conducting initial studies of the FAWT concept. Embarking on the tests signifies the next step under a new framework. For the project, small-scale experimental versions of the FAWT will be installed in Japanese waters. After confirming the validity of the analysis and design method, this will lead to an even larger scale (megawatt class) offshore demonstration project.

The five companies involved in the project will use their individual expertise to jointly develop the FAWT, which is anticipated to be a ‘gamechanger’ in floating offshore wind power generation. Through this collaboration, they aim to make offshore wind power generation the primary source of electricity and contribute to the realization of a carbon-neutral society.

Roles of the cooperating organizations: The wind turbine section of the small-scale experimental units will be developed by Fukui Fibertech Co., Ltd. (Aichi Prefecture), and the floating section will be developed by Mirai Ships Inc. (Miyagi Prefecture). The carbon composite material moulding technology will be developed in partnership with the Innovative Composite Center (ICC) at the Kanazawa Institute of Technology, and the motion analysis technology will be developed in partnership with Osaka University’s Graduate School of Engineering.

Senior chemist Di-Jia Liu inspects catalyst sample inside tube furnace after heat treatment while postdoc Chenzhao Li carries a pressure reactor for catalyst synthesis.
Image Courtesy: Argonne National Laboratory

Clean fuel from water

A multi-institutional team led by the U.S. Department of Energy’s (DOE) Argonne National Laboratory has developed a low-cost catalyst for a process that yields clean hydrogen from water. Other contributors include DOE’s Sandia National Laboratories and Lawrence Berkeley National Laboratory, as well as Giner Inc.

Focusing on their work, Di-Jia Liu, Senior Chemist at Argonne who also holds a joint appointment in the Pritzker School of Molecular Engineering at the University of Chicago, said, “A process called electrolysis produces hydrogen and oxygen from water and has been around for more than a century.” Proton Exchange Membrane (PEM) electrolyzers represent a new generation of technology for this process. They can split water into hydrogen and oxygen with higher efficiency at near room temperature. The reduced energy demand makes them an ideal choice for producing clean hydrogen by using renewable but intermittent sources, such as solar and wind.

This electrolyzer runs with separate catalysts for each of its electrodes (cathode and anode). The cathode catalyst yields hydrogen, while the anode catalyst forms oxygen. A problem is that the anode catalyst uses iridium, which has a current market price of around $5,000 per ounce. The lack of supply and high cost of iridium pose a major barrier for widespread adoption of PEM electrolyzers.

The main ingredient in the new catalyst is cobalt, which is substantially cheaper than iridium. “We sought to develop a low-cost anode catalyst in a PEM electrolyzer that generates hydrogen at high throughput while consuming minimal energy. By using the cobalt-based catalyst prepared by our method, one could remove the main bottleneck of cost to producing clean hydrogen in an electrolyzer,” said Liu.

Giner Inc., a leading research and development company working toward commercialization of electrolyzers and fuel cells, evaluated the new catalyst using its PEM electrolyzer test stations under industrial operating conditions. The performance and durability far exceeded that of competitors’ catalysts.

Important to further advancing the catalyst performance is understanding the reaction mechanism at the atomic scale under electrolyzer operating conditions. The team deciphered critical structural changes that occur in the catalyst under operating conditions by using X-ray analyses at the Advanced Photon Source (APS) at Argonne. They also identified key catalyst features using electron microscopy at Sandia Labs and at Argonne’s Center for Nanoscale Materials (CNM). The APS and CNM are both DOE Office of Science user facilities.

Final words

The world of technology is changing very fast. Whether we will be able to limit the rise of mother earth’s temperature within 1.5 degree C or not, that’s a different question. But scientists are trying their level best to do that.

In today’s world, if a country succeeds in developing a new technology, the very technology or something parallel to it spreads fast. I have narrated only two recent developments here, however, lot of other developments are taking place around the globe. Therefore, we can keep hope to get back a clean world, where all sources of electrical energy will be clean.

By P. K. Chatterjee (PK)

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