From PV Curtailment to 30% Revenue Boost: The Poustka PV Plant Upgrade in the Czech

Located in the rolling green valleys of western Czech Republic, the Poustka PV plant unlocked the full potential of its solar generation in June 2025 with the installation of an advanced energy storage system. With a total capacity of 6.88 MWh, the PV plant is powered by Hoymiles’ HoyPrime containerized battery energy storage system and the HIM Series PCS-MV Station. This project not only resolved PV curtailment but also maximized energy value through time-of-use optimization.

SPL a.s., an established pioneer in the Czech renewable energy sector, manages a diverse portfolio spanning solar PV, hydropower, and second-generation biofuels. With years of expertise, the company has successfully operated several PV plants, including Poustka.

Yet, despite stable power generation, the Poustka PV plant faced persistent challenges. Limited grid capacity during peak hours often led to wasted solar energy. Volatile time-of-use tariffs restricted profitability, while grid-imposed power restrictions further limited the plant’s output. For SPL a.s., the need for a reliable energy storage solution became urgent—one that could eliminate waste, stabilize operations, and secure sustainable financial returns.

Two months ago, Hoymiles partnered with SPL a.s. to deliver a customized energy storage solution designed to overcome these barriers. The system integrated the HoyPrime containerized battery system with the HIM Series PCS-MV Station, creating a highly efficient and collaborative setup for power generation, storage, and grid interaction.

The project also marked SPL a.s.’s first demonstration of a fully integrated PV + storage model. Despite construction challenges such as summer heat and complex device installations, the Hoymiles team provided on-site guidance throughout, ensuring timely commissioning with excellent quality. As one SPL a.s. representative recalled:

“The installation wasn’t easy, but the Hoymiles team impressed us with their thorough preparation and flexible response. Their professionalism made sure everything was completed on time and to a high standard,” said a Poustka representative when looking back on the installation work.

Since going live, the Poustka PV plant has seen a dramatic transformation. PV curtailment during peak hours has been virtually eliminated, with excess solar energy stored and released precisely when needed. Operational data shows that revenues increased by over 30%, thanks to optimized use of time-of-use tariffs.

Beyond direct revenue gains, the system is also qualified for grid regulation services, opening new income streams for SPL a.s. Moreover, the plant achieved local green energy certification, further strengthening the company’s sustainability credentials.

As an SPL a.s. representative noted:

“This is our first time using Hoymiles products, but certainly not the last. The system not only makes our plant more efficient, but also realizes a more sustainable operation mode as we move along.”

This project represents more than a simple upgrade. It is a showcase of how advanced energy storage can transform renewable power plants into flexible, profitable, and future-ready energy hubs. For Hoymiles, the success at Poustka marks another step in helping to drive the global energy transition by delivering reliable, intelligent solutions that maximize energy value for partners around the world.