There have been significant changes in environmental requirements since many of these facilities came online, and some plants may face high costs and difficult engineering tasks as they try to comply with new rules and maintain operations. Adding screens that essentially filter out fish from the hydroelectric plant's intake is a potential solution in some cases, but both installation and maintenance of these systems can add significant costs. For these facilities, Natel's technology represents an alternative, Schneider says.
Natel has installed several projects in Maine, Oregon and Austria. They all use relatively small turbines, but the company is working on larger projects and recently won a bid process with a manufacturing partner to supply a 3-meter diameter turbine to an existing plant, Schnieder said. The company is also licensing its fish-safe turbine design to existing manufacturers.
Whether a utility adopts a fish-safe design will depend on how it affects efficiency or how much energy can be captured by a given water flow. In some cases, Natel’s turbine design will be slightly less efficient than today’s existing turbine designs, Schneider says. But the differences are minimal and will likely still be an improvement over previous designs.
There is sometimes a trade-off between fish safety design and efficiency, but not all new turbines are like that. A 2019 study by the U.S. Army Corps of Engineers found that one new design produced more power while improving fish safety.
However, installing new turbines at a hydroelectric power plant does not solve all the environmental problems associated with that technology. For example, the new equipment is only relevant for downstream migration, such as when eels move from freshwater rivers to the ocean to breed. Other solutions are still needed to allow for an upstream migration path.
Ideally, the best solution for many plants would be a natural bypass or ramp, which allows many species to pass freely in both directions. However, due to space requirements, these are not always possible to install or use.
![""](https://wp.technologyreview.com/wp-content/uploads/2024/06/Natel-CTO-Abe-Schneider-with-an-extra-large-trout-that-passed-safely-through-a-Restoration-Hydro-Turbine-at-the-Monroe-Hydro-Plant-in-Madras-Oregon.jpg?w=2460)
Natel
Michael Milstein, senior public affairs officer for NOAA Fisheries, part of the National Oceanic and Atmospheric Administration, says people have been trying to improve fish passage for a long time. Current solutions include fish ladders, where fish swim or jump to successively higher pools to get through the dam. Other dams are too high for that, so fish are caught and trucked around.
The challenge, Milstein says, is that “every river is different and every dam is different.” He adds that solutions must be tailored to each individual situation. When there is no bypass and the fish have no other option but to go through the facility, fish-safe turbines will be paramount.