In a significant advancement for the renewable energy sector, researchers have introduced a novel low‐head pumped hydro storage system that could transform how we balance energy supply and demand, particularly in coastal and shallow sea environments. This innovative technology is designed to address the pressing challenges associated with traditional pumped hydro systems, which often struggle with efficiency and scalability in low-head applications.
Justus Peter Hoffstaedt, a lead author from the Faculty of Mechanical Engineering at Delft University of Technology, emphasizes the importance of this development in the context of the ongoing energy transition. “Large-scale energy storage solutions are essential for ensuring grid stability and reliability as we shift towards a low-carbon, renewable energy-based electricity supply,” Hoffstaedt stated. The new system’s design incorporates several units of contra-rotating reversible pump-turbines linked to axial-flux motor generators, all within a strategically designed ring dike. This configuration allows for independent control of each turbine, enabling the system to adapt to varying operational conditions effectively.
The researchers conducted extensive numerical simulations to evaluate the system’s performance across different scenarios, including energy generation, storage, and grid support for a 1 GW system with 4 GWh of storage capacity. The data revealed that the low-head pumped hydro storage system could achieve round-trip efficiencies exceeding 70%, a remarkable feat that enhances its commercial viability. By increasing the maximum power of the electric machines, the system can also expand its maximum head range, resulting in a threefold increase in energy density per unit area.
The implications of this research extend beyond just efficiency. The dynamic simulations indicated that the system could rapidly adjust its power output, a critical feature for providing frequency regulation services to the grid. “Allocating 20% of its nominal power as a reserve, the new power setpoints can be reached within a maximum of 5 seconds, independent of its initial state of charge,” Hoffstaedt noted. This rapid response capability positions the technology as a valuable asset for grid operators, particularly as the integration of variable renewable energy sources like wind and solar continues to grow.
As the energy sector grapples with the challenges of integrating renewables while maintaining grid stability, Hoffstaedt’s research offers a promising solution. The low-head pumped hydro storage system could play a pivotal role in enhancing frequency stability and supporting power grids in a sustainable manner. The findings are published in the journal ‘IET Renewable Power Generation’ (translated as ‘IET Renewable Power Generation’), highlighting the potential of this technology to reshape energy storage strategies.
For more information on this groundbreaking research, you can visit the Delft University of Technology’s website at Delft University of Technology. This development not only signifies a leap in energy storage capabilities but also sets the stage for future innovations that could redefine energy management in a low-carbon world.
