Environment Agency includes Natel’s FishSafe™ turbines in Best Achievable Eel Protection guidance

Bristol, United Kingdom, February 2025 – The UK’s Environment Agency has confirmed the inclusion of Natel's FishSafe RHT within their Best Achievable Eel Protection guidance. 

This decision follows an in-depth review of multiple reports and scientific evidence, including a 2022 peer-reviewed study that found 100% immediate and 48-hour survival for eels up to 66 cm (26 in). Additionally, the agency reviewed 2023 test results documenting eel passage through a turbine operating at tip speeds up to 28 m/s—that’s 63 mph, or 101 km/h—conditions that closely match real-world hydropower operations. That study recorded 100% immediate and 99.2% 48-hour survival for eels.

Based on this assessment, the Environment Agency has concluded that Natel’s hydropower turbine designs will pose minimal risk to entrained migrating eels. The agency is responsible for protecting and enhancing England’s environment, including its freshwater and migratory fish populations.

Freshwater eels play a vital role in aquatic ecosystems, but their populations have declined dramatically in recent decades. The European eel is now critically endangered, facing a greater risk of extinction than the giant panda or blue whale, according to the International Union for Conservation of Nature. Historically, they made up over 50% of fish biomass in some European freshwater environments, feeding a host of other species like otters and herons and providing valuable stock for commercial fisheries.

The causes of eel decline are multifold, but one major challenge to eels has been hydropower turbines, which can cause significant injury or mortality when eels migrate downstream. With the right design, however, hydropower turbines can protect these important fish while also producing baseload renewable energy.

In addition to allowing >99% through-turbine downstream passage survival for eels, Natel’s FishSafe designs can directly replace existing turbines or turbine runners. Plant owners can thereby upgrade to FishSafe equipment with minimal additional cost and no sacrifice of output or efficiency. When FishSafe turbines satisfy downstream fish passage requirements, they offer the lowest total cost of ownership and fastest return on investment over conventional turbines paired with conventional fish protection measures. 

This recognition from the Environment Agency sets a new benchmark for downstream fish passage at hydropower plants in Europe. Natel is excited to begin implementing projects in the UK and to make a difference for eels and other migratory fish globally.

About Natel Energy

Natel Energy is a technology & engineering company working to support healthy rivers, promote biodiversity and decarbonize the grid by developing hydropower turbines that enable 98-100% downstream passage survival for fish. Natel delivers high-performance FishSafe™ turbine designs informed by industry-leading CFD modeling and analysis. Natel conducts feasibility studies, performs fish passage and performance testing, and works with trusted turbine manufacturers to implement its runner designs worldwide. Natel is a privately held company located in Alameda, California in the United States. Visit www.natelenergy.com for more information.

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