Natel’s Restoration Hydro Turbine (RHT) enables safe downstream passage across fish species.

What Fish-Safe Means

A “fish-safe” turbine causes negligible injury or mortality to all resident and migratory fish species at all life stages, as compared to natural hazards encountered during a fish’s life cycle.

Abe Schneider holds an eel.

We conduct original fish passage science and apply a data-informed approach to creating renewable energy solutions that are truly fish-safe.

Why Fish-Safe Turbines?

Downstream migrating fish want to go with the flow, but the conventional approach to fish protection at hydropower plants relies on screening to route fish around turbines through low-flow fishways. This can delay migrations and expose fish to predators. Additionally, many fish still enter turbines where they are subject to traumatic injuries or death. Screened turbines are less effective at protecting fish than fish-safe turbines.

Data-Informed Design

Sterling Watson lifts a large trout out of a holding tank during a fish passage test at the Monroe Hydro Plant.

From the beginning, collecting information about how real fish interact with the Restoration Hydro Turbine has been an integral part of our design process. We’ve performed controlled laboratory and field studies with biologists and engineering partners from Alden Research Laboratory, Pacific Northwest National Laboratory, and Kleinschmidt Associates to understand the effects of the RHT on migratory fish species across a range of operating conditions.

Read our peer-reviewed study in the Journal of Ecohydraulics examining how turbine blade angle and thickness affect survival rates in rainbow trout:
"Improving Survival: Injury and Mortality of Fish Struck by Blades with Slanted, Blunt Leading Edges."


Read our peer-reviewed study in Transactions of the American Fisheries Society documenting a 100% survival rate for American eel passing through the RHT:
"Safe Passage of American Eel Through A Novel Hydropower Turbine."

Read our peer-reviewed study in North American Journal of Fisheries Management demonstrating that the RHT, which is designed for fish safety, is an effective way to pass juvenile alosines downstream at hydropower facilities:
"Juvenile Alewife Passage through a Compact Hydropower Turbine Designed for Fish Safety."

Why is Live Fish Passage Testing Important?

Natel’s commitment to design and build the most fish-safe, high-performance, compact turbines in the world places fish and their safety at the center of all we do. To learn how to protect fish best, the use of fish in scientific research remains critical to the development of safe and responsible hydropower.

The humane treatment of all fish used for hydropower turbine testing is vital, both ethically and scientifically. If the fish are not treated well, the research results are not useful since they cannot be replicated, a critical hallmark of the scientific method.

Our researchers are strong advocates of animal welfare and view their work with fish as a privilege. We take our responsibility for the ethical treatment of fish in our research very seriously and abide by all rules and regulations dictated by the American Fisheries Society’s Guideline for Use of Fishes in Research. Furthermore, we ensure compliance with the National Institutes of Health Office of Laboratory Animal Welfare and their Public Health Service Policy on Humane Care on Use of Laboratory Animals.