Precision Flow Measurement for High-Efficiency Hydropower

Hydropower’s Renewed Relevance in a Power System That Must Be Both Clean and Controllable

Hydroelectric power generation is more than ever a secure and reliable source of electricity generation. This is not only due to the fact of being a 100% renewable energy source, but equally because of its stabilizing effect on frequency regulation in the power grid - a technical feature that becomes increasingly important as energy production from wind and solar continues to grow. The strategic value of a hydropower plant therefore lies not only in the amount of sustainable energy it generates, but in its ability to stabilize frequency, provide reserves and shift energy across time. Storage and pumped-storage power plants stand out in particular. This shifts the benchmark: hydropower is measured not only by its generated electrical power, but by efficiency, reliability and the robust quantification of performance and losses.

Regarding the efficient operation of hydroelectric power plants, accurate water flow measurement becomes one of the critical factor. Electrical power is proportional to flow rate, to the difference in elevation between water intake and turbine and to the turbine- and power generator efficiency. The flow through a turbine or pump-turbine is the most difficult quantity to determine. Uncertainties in flow measurement have a direct impact into calculated efficiency. International standards such as IEC 60041 and ASME PTC 18 therefore define methods how the flow rate shall be measured to calculate efficiency. In practice, however, the conditions are very complex: large, often difficult-to-access pressure pipelines, disturbed flow profiles and the requirement to measure during operation without impacting availability.

This is where GWF's expertise in ultrasonic flow measurement comes into play. Multi-path ultrasonic technology in particular measures the velocity field across the entire cross-section, reduces sensitivity to local disturbances and enables precise and reliable calculation of total flow. GWF's Ductus flow meter, equipped with integrated self-diagnostics, processes up to 20 ultrasonic paths simultaneously, ensuring the highest measurement accuracy even in short and complex situations with the resulting disturbed flow velocity profiles. Safe and reliable operation of pumped-storage applications is thereby guaranteed. Greater confidence in flow measurement means greater confidence in efficiency and thus better operational decisions, early detection of performance losses and robust acceptance testing.