# Greenvolt picks BYD Haohan for Poland's largest battery, a 600 MW / 2.4 GWh plant at Siedlce

Canonical page: https://technooptimist.io/stories/greenvolt-picks-byd-haohan-for-poland-s-largest-battery-a-600-mw-2-4-a97a5788
Date: 1 Jul 2026
About: [BYD](https://technooptimist.io/companies/byd.md) · [Haohan / MC Cube grid storage](https://technooptimist.io/energy/byd-grid-storage.md)
Original source: https://www.ess-news.com/2026/07/01/greenvolt-byd-energy-sign-supply-deal-for-600-mw-bess-in-poland/

Greenvolt Power signed a supply deal with BYD Energy Storage for Haohan systems at Siedlce, a 600 MW / 2.4 GWh plant that will be Poland's largest battery and one of Europe's largest. Construction starts in the third quarter of 2026, with commercial operation targeted for the end of 2027; the plant already has revenue from Poland's capacity market.

## Key facts

- Builds on 2025 deals for two 200 MW / 800 MWh Polish sites (1.6 GWh combined).
- Revenue secured through Poland's capacity market.
- Commercial operation targeted for end-2027.

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