With energy storage systems (ESS) increasingly deployed in commercial centres and residential areas, noise levels have become a critical factor for project approval. Hoymiles’ HoyUltra 2, its liquid-cooled C&I battery system, has achieved≤60 dB noise level certification in a noise evaluation test conducted according to the international ISO 3744:2010 standard by the Zhejiang Electric Safety and Quality Inspection Centre. While the industry average is 65–75 dB, the breakthrough certification of HoyUltra 2 sets it apart as one of the quietest in the industry.
Unlike tests conducted in noisy industrial environments, HoyUltra 2 was tested in a professional semi-anechoic chamber with a background noise level of just 24 dB—quieter than a bedroom at night. The evaluation covered the system’s entire operational cycle, including full-power charging and discharging, the results confirming that even under maximum load, the noise remains consistently low and stable, free from a mechanical hum.
The breakthrough enables the product to blend seamlessly into noise-sensitive environments, including commercial business districts, industrial parks and residential communities.
The silence of the HoyUltra 2 is the result of “System-Level Quiet Engineering”, which integrates acoustics into product design from the very beginning, addressing multi-dimensional noise suppression, the balance of efficiency and quietness, fully liquid-cooling architecture and acoustic stability and control. .