A recent study by researchers at the Otto von Guericke University Magdeburg [52.1°N, 11.6°E] addresses a pressing challenge in hydropower: the risk of injury and mortality to fish passing through turbines. Hydropower is a crucial component of renewable energy systems, yet its ecological impact has long been a concern, particularly for aquatic ecosystems. This research introduces an innovative laboratory blade strike rig to test and refine turbine designs, making them safer for fish while improving the overall sustainability of hydropower.
The Problem: Hydropower and Aquatic Ecosystems
Hydropower facilities often disrupt river ecosystems, particularly for fish migrating downstream. Many fish face risks from mechanical collisions with turbine blades, which can lead to high mortality rates. Current methods to address this include bypass systems and field testing with live fish. However:
- Bypass systems are not always effective, with up to 88% of fish still passing through turbines in some cases.
- Live fish testing, while valuable, is expensive, difficult to standardise, and raises ethical concerns.
The study highlights that as hydropower expands globally, these challenges require innovative solutions to balance renewable energy production with ecological preservation.
The Innovation: A New Testing Rig
The research team developed a digitally controlled blade strike rig that offers unprecedented precision and control. This open-access design allows researchers to evaluate fish injury risks and turbine designs without relying on live fish.
Key Features:
- Controlled Blade Velocities: The rig achieves speeds from 1 to 10 metres per second, closely simulating real turbine conditions.
- Standardisation: Unlike previous methods, this rig provides repeatable and comparable data for different turbine designs.
- Flexibility: It supports testing for both live fish and sensor probes, enabling researchers to gather comprehensive data.
Findings: Tests with sensor probes revealed that the commonly used 95g acceleration threshold, often assumed to predict fish injuries, may overestimate risks. This calls for refined injury models based on more accurate measurements.
Implications for Hydropower
This research bridges the gap between energy production and ecological conservation by:
- Guiding Safer Designs: The rig helps optimise turbine blades to reduce fish injuries, supporting a transition to fish-friendly hydropower.
- Reducing Costs: With fewer live fish tests needed, hydropower operators can save on expensive ecological assessments.
- Promoting Sustainability: By addressing ecological concerns, hydropower becomes a more balanced renewable energy source.
A Sustainable Future for Rivers and Energy
The study provides a vital tool for modernising hydropower systems, many of which were built decades ago. By prioritising ecological safety alongside renewable energy goals, this research lays the groundwork for a future where clean energy does not come at the expense of biodiversity.
Source
An Open Laboratory Blade Strike Rig to Evaluate the Risk of Injury and Mortality to Fish and Test Passive Sensors, Sustainable Energy Technologies and Assessments, 2025-01-25
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