NTNU Energi

Water turbines must live longer

Skrevet av NTNU Energi | Sep 19, 2023 11:56:38 AM

Jim Abregu believes that we are working in the right direction to support a better world with green energy by increasing turbine lifetimes. 

This is a blog post. The opinions expressed here are those of the author.

I believe that we are working in the right direction to support a better world with green energy by increasing turbine lifetimes.

 

The global change to clean and affordable energy requires hydraulic turbines that support higher demands and can handle high sediment loads. We are investigating erosion in Pelton turbines, which is a key factor in the turbine’s operating life. It occurs due to sediments in rivers, mainly near mountains like the Alps, the Himalayas, and the Andes. These are the areas where new hydroelectric projects are located.

By studying how the water hits the so-called buckets of the turbines (shaded area above my finger), we can learn more about turbine design to increase its lifetime. Photo: Maren Agdestein/NTNU
 

More starts and stops, and more sediment in the rivers

The new renewable energy sources like wind and solar require support to keep the electricity grid stable. Hydroelectric turbines are the best choice for this job (in Norway). But the exigency on the turbine increases with rapid load variations, and more starts and stops.

 

Additionally, climate change brings erratic patterns in the sediment load in the rivers. We need to have a better understanding of erosion in turbines to improve their design, thus increasing the lifetime of the turbine.

During experiments, water shoots out of the nozzle and hits the buckets at a high velocity. Photo: Maren Agdestein

High-speed camera to study the details

We are using the Pelton test rig at Waterpower Laboratory. We have a high-speed camera installed within the turbine runner looking at one of the buckets. That allows us to verify numerical analyses of the flow inside the turbine and better understand erosion mechanisms.

 
About the author

Jim Abregu is a PhD Candidate at NTNU – Department of Energy and Process Engineering, affiliated with FME HydroCen, a Centre for Environment-friendly Energi Research (FME).