Elis Co., Ltd., based in Okayama Prefecture, Japan, is garnering global attention for its small hydropower technology, which boasts enhanced efficiency through innovation. The company’s system adjusts the weir wall and turbine position to harness water flow dynamically, enabling stable power generation year-round even with fluctuating water volumes. This flexibility makes it ideal for agricultural irrigation channels, reducing production costs and facilitating IT integration.

Elis’s hydropower technology features a movable weir wall that adjusts in response to changes in water flow. Combined with a mechanism that raises or lowers the turbine, this design ensures optimal water flow angles for efficient power generation, overcoming efficiency losses caused by water level fluctuations. Extensive research into turbine blade angles and configurations has further enhanced performance.

The turbine operates by skimming water from the surface, allowing debris to pass beneath, simplifying maintenance. Additionally, the system is fish-friendly, minimizing environmental impact.

Founded in 2001, Elis obtained a patent for its advanced small hydropower technology in 2020 and began installation in Niigata Prefecture in 2021, with plans to commence electricity sales in December. With patents in 55 countries, the company is receiving strong interest from Europe, where environmental awareness drives demand, and emerging markets like Ethiopia, where infrastructure development is ongoing.

Elis’s system benefits from Japan’s feed-in tariff (FIT) scheme, which offers higher buyback rates for small hydropower (34 yen/kWh) compared to solar (9.2–16 yen/kWh). A single unit, measuring 1.5 meters wide, generates 20 kW, with installation costs ranging from 50 to 60 million yen, enabling a payback period of 10–15 years.

Unlike dams, small hydropower requires less water and smaller infrastructure, making it cost-effective. Unlike solar and wind, it is less dependent on weather conditions, ensuring stable, efficient power generation.

Elis plans to collaborate with local farmers to integrate its hydropower technology into greenhouse horticulture, reducing electricity costs and supporting high-value crop production. The technology also helps lower carbon footprints and integrates IoT and AI for remote monitoring. Beyond agriculture, it has potential applications in disaster resilience, regional industry promotion, and job creation, contributing to a sustainable green economy. (Souta Nakano)

Nikkei Shimbun