Waste Bamboo Turns into Fuel: HIROTEC and Kindai University Achieve Successful Demonstration

HIROTEC CORPORATION (headquartered in Saeki Ward, Hiroshima City, Hiroshima Prefecture; hereinafter "the Company"), a global engineering company specializing in automotive components, has successfully demonstrated the prototype production of "bio-formed coal" comparable to conventional coal coke. This achievement was made through joint research with the Faculty of Engineering at Kindai University (Higashi-Hiroshima City, Hiroshima Prefecture) under the Company's internal new business program, "HIROTEC neXt Biz Challenge" (hereinafter "HIROCHARE"), as its first project, the "Oyster Upscale" initiative. The bio-formed coal uses waste bamboo materials (primarily oyster farming rafts) generated in Hiroshima Prefecture and surrounding areas as its main raw material.

By combining HIROTEC's long-standing press forming and production technologies from the automotive industry with material development and raw material processing expertise from Professor Kohei Shiraishi of the Department of Chemical and Life Engineering at Kindai University's Faculty of Engineering, the project successfully produced bio-formed coal with heat output equivalent to existing coal coke and high density matching industrial standards. Detailed evaluations of the prototype's mechanical properties and combustion efficiency were conducted at Kindai University's Faculty of Engineering and completed by the end of April 2026. Moving forward, the Company aims to commercialize the product by the end of 2026, positioning it as an additive that contributes to CO2 reduction when blended into coal for combustion, and as a combustion-efficiency booster during the transition from coal to biomass fuels.

[Key Points of This Release]

● Resource utilization of 5,000 tons of waste bamboo

Targeting resource recovery using approximately 5,000 tons of waste bamboo (mainly oyster farming rafts) generated annually in Hiroshima Prefecture and nearby areas as the primary raw material

● Performance comparable to coal coke

Achieved high-density formation through press molding technology; compatible with existing coal-fired equipment without modification

● Minimized adverse effects on combustion furnaces

Significantly reduced potassium, chlorine, and sodium—elements known to cause furnace corrosion

● Scientific validation through industry-academia collaboration

Material and mechanical properties evaluated at Kindai University's Faculty of Engineering; evaluation completed by the end of April 2026

● Targeting commercialization by end of 2026

Planning sales to power generation companies and material industries

● Business concept developed by the second cohort of HIROCHARE, the Company's internal startup program

Employees with expertise in automotive components conceived and advanced the project from scratch

Background of Development: Annual 5,000 Tons of Waste Bamboo and the Accelerating Trend of "Returning to Coal"

Hiroshima Prefecture accounts for about 60% of Japan’s oyster production, making it a major production hub. However, the disposal of used bamboo rafts after their service life has become a significant environmental challenge for local communities. Approximately 5,000 tons of waste bamboo from oyster farming are generated annually, most of which is currently disposed of by open burning, raising concerns about CO2 emissions and impacts on neighboring areas. To address this issue, the Company collaborated with Maruei Co., Ltd., which has been working with the Hiroshima Prefectural Fisheries Cooperative and local fishing cooperatives to establish a regional circular economy model for sourcing waste oyster rafts, ultimately enabling the successful development of bio-formed coal.

Meanwhile, globally, electricity demand from data centers due to the rapid spread of generative AI, along with energy security concerns, has led to a short-term increase in reliance on coal. Coal demand remains high, with the International Energy Agency (IEA) reporting that global coal consumption reached a record high of approximately 8.7 billion tons in 2024. In Japan, a greenhouse gas emissions trading scheme (GX-ETS) will fully launch in spring 2026, targeting around 300–400 businesses whose annual average CO2 emissions exceed 100,000 tons. This places increasing pressure on companies to reduce emissions. Given the reality that coal cannot be immediately phased out and the growing cost burden of emission allowances, biomass-based supplementary fuels or additives that can be directly fed into existing coal infrastructure while maintaining combustion efficiency and reducing CO2 emission intensity are gaining attention as practical decarbonization solutions during the transition period.

Additionally, domestically, the use of "carbon offsetting"—compensating for unavoidable CO2 emissions through credits from reforestation or renewable energy projects—is rapidly spreading across construction, transportation, and material industries. With the emergence of environmentally certified carbon offset products under Japan’s Ministry of the Environment, efforts to achieve carbon neutrality by combining "real emission reductions" with "effective decarbonization via credit utilization" are gaining momentum. HIROTEC’s bio-formed coal aims to serve as a direct solution within this framework, strengthening the portfolio of tangible, real-decarbonization tools that can be integrated into various industries’ decarbonization strategies.

In this context, HIROTEC launched the internal new business project "Oyster Upscale" to apply its automotive component press-forming technologies to solve regional environmental challenges. In collaboration with Kindai University's Faculty of Engineering, the Company has advanced demonstration experiments toward the practical application of bio-formed coal using waste bamboo as the primary raw material, achieving performance comparable to conventional coal and coal coke.

▲ Bio-formed coal jointly prototyped by HIROTEC and Kindai University (φ60mm × L40mm)

Overview of the Demonstration Experiment: Achieving High Density via Press Forming Technology

From February to March 2026, joint tests were conducted using HIROTEC’s press equipment under the following conditions:

Main Raw Material

Bamboo charcoal derived from waste oyster rafts + waste-derived binder

Prototype

Cylindrical shape (test piece): φ60mm × L40mm

Evaluation Body

Faculty of Engineering, Kindai University (and related institutions)

[Process from Raw Material to Final Product]

1 Waste oyster rafts (bamboo) → 2 Bamboo charcoal after carbonization and pulverization → 3 Bio-formed coal after press forming

After numerous trials in powder forming, high-quality formed coal was successfully produced. The following three points represent key technical features enabling future mass production:

1 Optimized particle size of bamboo charcoal

By optimizing particle size, uniform shaping and high-density products became achievable.

2 Reduced production time

Increased pressing force shortened both heating and pressing durations, improving production speed.

3 Optimized mold temperature

Adjusting mold temperature allowed smooth product ejection with minimal use of anti-sticking agents.

Industry-Academia Collaboration with Kindai University's Faculty of Engineering

Kindai University's Faculty of Engineering actively promotes research contributing to a sustainable society. In this project, the University contributed its expertise and facilities in optimizing the pulverization and carbonization conditions of waste bamboo, as well as in evaluating the mechanical properties of the formed coal. By combining HIROTEC’s press-forming technology as an automotive parts manufacturer with the University’s materials science knowledge, the project has scientifically validated and established practical-level product quality.

Upscale Business Utilizing HIROTEC’s Press-Forming Technology

HIROTEC has traditionally focused on mold design, manufacturing, and press processing for automotive body components such as doors. The high-pressure forming technology using large-scale presses and mold design expertise developed through large automotive component manufacturing are directly applicable to this project’s high-density powder forming process.

In parallel with this initiative, the Company is also developing powder-forming technologies for other products primarily using oyster shells, aiming to establish a new circular economy-based business centered on the "Oyster Upscale" concept.

Future Outlook: Collaboration with Companies Using Coal Combustion Systems and Commercialization

Going forward, the Company will promote this product to heat supply and power generation companies, as well as manufacturers, as an additive that reduces CO2 emissions when blended into coal combustion, and as a combustion-efficiency enhancer during the fuel transition from coal to biomass. The Company also plans to exhibit at energy and building materials trade shows to explore diversified applications. As a company headquartered in Hiroshima—a hub of oyster industry—the Company aims to contribute to regional resource circulation and reduced environmental impact through this business.

Comment from Professor Shiraishi, Faculty of Engineering, Kindai University

At the Laboratory of Biomaterials Chemistry, Department of Chemical and Life Engineering, Kindai University, we have been developing recycling technologies for difficult-to-recycle waste plastics, supported by Professor Taminori Ida of the Kindai University Bio-Coke Research Institute. Previously, our lab has advanced research—under the NPO Hiroshima Organization for Promotion of a Recycling Society—on producing mixed bio-coke from waste plastics and biomass resources such as waste bamboo. This time, we successfully developed a method to produce bamboo charcoal/waste plastic bio-coke with a density of approximately 1.0 g/cm3 (up to 1.3 g/cm3 by adjusting plastic content) within minutes, using only 5–10 wt% waste plastic (dependent on plastic type). While biomass resources often require high-energy processes and specialized mills to pulverize below 1 mm, carbonized materials are easier to grind. Combining pulverized charcoal with waste plastics significantly improves processing time and temperature, enabling room-temperature preparation in as little as five minutes—made possible only by HIROTEC CORPORATION’s high-pressure forming technology. Waste plastics from oyster raft floats or cover sheets can be used. Furthermore, utilizing waste heat from HIROTEC’s other production processes for carbonization and solidification opens the possibility of continuous production, making the goal of 50% CO2 reduction by 2030 increasingly realistic.

About HIROCHARE (Internal New Business Program)

The "Oyster Upscale" project was conceived by the second cohort of HIROTEC CORPORATION’s internal startup program, "HIROCHARE."

While the Company has traditionally centered on automotive component manufacturing and development, the rapid advancement of electrification and automation in the automotive industry has made it urgent to reduce dependency on this sector and diversify business areas. To directly address this challenge, employees with automotive industry expertise initiated this project, challenging themselves in an entirely new field and driving a zero-based business concept from inception.

Through "HIROCHARE," HIROTEC aims to foster an organizational culture where every employee can continuously explore new industries and ventures, driving corporate transformation to navigate the pivotal transition in the automotive industry.

[Company Overview]

Company Name

HIROTEC CORPORATION

Head Office Address

5-2-1 Ishiuchi-Minami, Saeki Ward, Hiroshima City, Hiroshima Prefecture

Business Activities

Design and manufacture of automotive components (doors, exhaust system parts), molds, jigs, and assembly lines

Corporate Website

https://www.hirotec.co.jp/