While most people do not pay much attention to the electric power grid except when there are issues, pumped storage plants rarely receive attention unless and until they become a critical part of the overall system. Therefore, the recent Voith Hydro’s award in Switzerland to upgrade an existing pumped storage plant in Switzerland may reflect how ordinary-looking infrastructure decisions have important implications.
A pumped-storage site built for those “uncomfortable” moments
When supply rapidly changes or demand increases suddenly, pumped storage plants are expected to help correct these rapid changes quietly, without creating a public relations issue for plant owners. Therefore, pumped storage plants act as a stabilizer for the electric power system rather than a generator of headlines.
As more renewable resources are added to the electric generation mix, flexibility in the form of storage is becoming increasingly important. Instead of building new conventional generation capacity, utilities are relying more and more on storage to mitigate variability. Within this framework, new pumped storage developments are viewed as maintaining the integrity of the system rather than expanding capacity.
Grimsel 4 is situated in this reality. The purpose of the Grimsel 4 development is to improve the responsiveness of the Grimsel pumped storage plant to meet future grid needs. Like other aspects of the electric power system, as more renewable energy comes online, meeting future grid requirements becomes more difficult.
What Voith will install — and why the numbers matter
Voith Hydro recently received a contract for the Grimsel 4 pumped storage project. The scope of work included supplying and installing two variable-speed pump turbine sets along with their corresponding motor-generators. These components were selected to increase both pumping and generating capabilities at the site.
Each pump‑turbine set is rated at 70 MW. More importantly, the ability to vary speed permits the plant operator to react more quickly to changes in the system, thereby increasing the plant’s potential to be used as a flexible resource.
However, one key aspect is that the plant can produce that amount of capacity consistently and repeatedly. Therefore, although the quantity of capacity provided by a particular installation is a consideration, it is merely one component of determining whether or not that particular installation has produced economic value. Consequently, operators are concerned with not just providing capacity but also providing high-quality performance in delivering that capacity reliably and repeatedly.
Why Voith won the Grimsel 4 contract
Voith noted that it was successful in receiving the contract due to its competitive bid coupled with a technically sound solution based on proven hydraulic designs. This indicates that one major area of concern for developers and operators is that flexibility does not come at an increased level of risk.
Operators seek to create certainty in a large-scale network through pumped storage plants. Operators view equipment selection as a way to minimize risk in a large-scale network. Thus, selecting tried-and-true solutions as opposed to innovative solutions demonstrates that operators prioritize reliability over innovation in assets used to stabilize larger-scale networks.
The Grimsel 4 project marks another significant step forward in the partnership between Voith and the project owner. Additionally, beyond the boundaries of Grimsel 4 itself, Voith demonstrated that suppliers who provide dependable products are rewarded by operators seeking innovative approaches to meet future demands while minimizing risk.
What does this mean for Europe’s build-out of storage?
The decision regarding Grimsel 4 illustrated how much value lies in developing reliable access to stored capacity alongside added capacity. As European grids rely more heavily on intermittent energy sources, projects that enhance flexibility while reducing risk will attract growing interest. Ultimately, the value of a pumped storage project lies in its ability to provide consistent support to maintain electrical system stability.
