Pima Energy Storage System: 10 MW Pumped Hydro Storage in Tucson, Arizona

Pima Energy Storage System is a pumped hydro storage facility located in Tucson, Arizona, United States. With a capacity of 10 MW, it operates as a medium-scale energy storage plant, supporting grid stability and renewable energy integration in the region. The facility uses pumped hydro technology, which stores energy by pumping water to an upper reservoir and releasing it through turbines to generate electricity. In the United States, pumped hydro storage is the most mature and widely deployed grid-scale storage technology, accounting for the majority of installed storage capacity. The plant operates under the regulatory framework of the Federal Energy Regulatory Commission (FERC) and adheres to safety standards such as NFPA 855 for energy storage systems. Pima Energy Storage System plays a key role in the local grid by providing peak shaving and frequency response services. Its location in Arizona, a state with high solar penetration, helps mitigate the intermittency of renewable energy. The facility contributes to grid reliability and supports the transition to a cleaner energy mix in the region.

Pumped hydro storage facilities like Pima Energy Storage System involve the use of two reservoirs at different elevations, which can impact local hydrology and ecosystems. The operation of such plants requires careful management of water resources and consideration of downstream effects. In arid regions like Arizona, water use and evaporation losses are important environmental factors. Additionally, the facility's role in integrating variable renewable energy sources helps reduce greenhouse gas emissions by enabling higher penetration of solar and wind power.