Advancements in Renewable Energy Control Technology for CO2 Reduction Demonstrated by Pacific Consultants

Achievements in Renewable Energy Control Technology

Pacific Consultants Co., Ltd., based in Chiyoda Ward, Tokyo, and its group company Pacific Power Co., Ltd., have successfully concluded a project focused on developing and demonstrating optimal control technology for renewable energy based on hourly CO2 emission coefficients. This initiative falls under the Ministry of the Environment's program aimed at fostering regional collaboration for carbon neutrality through advanced technological solutions.

Overview and Objectives of the Technologies Developed

On September 9, 2024, Pacific Consultants and Pacific Power publicly announced their independently calculated hourly CO2 emission coefficients. These coefficients illustrate that CO2 emissions result from electricity generation and are not constant throughout the day; rather, they fluctuate based on various factors. For instance, cleaner electricity generation occurs during sunny weather due to a higher proportion of renewable energy, in contrast to times of rain or peak hours when fossil fuel-generated electricity predominates, leading to increased CO2 emissions.

The goal of the hourly CO2 emission coefficients is to visualize the temporal variations in CO2 emission intensity that are not captured by typical annual averages. By shifting electricity generation or consumption to different times, it is possible to achieve substantial reductions in CO2 emissions. Moreover, the technology developed during this project predicts the upcoming day’s CO2 emission coefficients and controls biogas power generation from wastewater treatment facilities, a renewable energy source that can be readily managed.

Demonstration Project Summary

The demonstration phase, conducted at the Fukuoka Chubu Power Plant (with a rated output of 1,999 kW), managed by Tsukishima JFE Aqua Solution Co., Ltd., utilized a project-specific control system. This plant, located at the Fukuoka Chubu Water Treatment Center, currently operates under a feed-in tariff (FIT) system for the complete sale of generated electricity.

The newly developed system functions by creating generation plans that maximize production during hours predicted to have higher hourly CO2 emission coefficients. This is achieved by sending commands to local generators to initiate power generation at optimal times. The system utilizes gas holders to temporarily store generated gas, ensuring that the production fits within predetermined maximum and minimum limits.

Control of Biogas Power Generation Using Gas Holders

The developed control system has efficiently demonstrated its ability to regulate power generation times based on the gas produced at the wastewater facility while maintaining a balance within the gas holders.

Outcomes of the Demonstration Project and Future Perspectives

During the demonstration period from February 12 to 21, 2025, the sold electricity quantities correlated significantly with the controlled hourly CO2 emission coefficients, showing about a 5% increase in CO2 reduction effectiveness compared to previous operational methods. Furthermore, transitioning from the FIT to the feed-in premium (FIP) system, evaluations based on the spot market prices indicated a roughly 7% increase in sales revenue. Throughout this period, the gas holders maintained appropriate upper and lower limits, ensuring all generated biogas was utilized effectively while optimizing the timing of power generation.

Visualization of Successful Control Outcomes

Pacific Consultants and Pacific Power aim to expand the application of their developed system to biogas power facilities across the country. This technology is adaptable not only to biogas from wastewater but also to other organic materials such as food waste and livestock manure. As announced on February 25, 2025, the new system will be applicable to installations generating electricity for self-consumption, further broadening its reach.

Pacific Consultants Group is committed to contributing to local energy initiatives, promoting community development, and advancing carbon neutrality efforts through sustainable practices.

About Pacific Consultants Co., Ltd.

Established in 1951, Pacific Consultants has over 70 years of experience as a leading construction consultancy. The company is deeply involved in the planning, design, and operation of various social infrastructures including urban development, transportation, and water management across Japan and internationally. Emphasizing the vision of 'Producing the Future,' Pacific Consultants aims to provide new value that contributes to a secure and sustainable society.

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