125kW/265kWh AC-Coupled ESS — Seamless Solar Retrofit in Romania

Location: Romania | System: Dawnice BS07-265-ES-X (125kW / 265kWh) | Application: AC-Coupled Solar Retrofit, Peak Shaving, Tariff Arbitrage

Dawnice has successfully deployed a 125kW/265kWh Commercial & Industrial (C&I) All-In-One Energy Storage System (ESS) in Romania. Utilizing an advanced AC-coupling scheme, the system seamlessly integrates with the client's existing 450kW Solar PV array and 450kW Huawei grid-tied inverters. As the first commissioned test unit of a planned 6-unit parallel system, this solution optimizes energy efficiency through smart peak-valley tariff arbitrage, significantly maximizing the client's ROI and accelerating their transition to green energy.

Project Background

With fluctuating commercial electricity tariffs across Europe, businesses in Romania are actively seeking ways to mitigate rising operational costs. While this industrial client had previously installed a high-performing 450kW rooftop solar system with Huawei inverters, they lacked the flexibility to store excess energy for peak-rate hours.

To solve this challenge, Dawnice implemented an AC-coupled storage retrofit. By integrating our ESS directly onto the AC side, the client can now perform energy arbitrage without altering their existing solar infrastructure.

Project Highlights

1. 125kW/265kWh All-In-One ESS (First Unit of 6-Unit Planned Project)

The successful commissioning of the first 125kW/265kWh cabinet paves the way for a total deployment of 6 parallel units. This modular scalability highlights the flexibility of Dawnice solutions to meet expanding energy demands for large-scale factories and commercial facilities.

2. Seamless Retrofit via Advanced AC-Coupling

The system integrates effortlessly with the pre-existing 450kW solar panels and 450kW Huawei grid-tied inverters on the AC side. This elimination of DC-side rewiring dramatically reduces installation time and onsite labor costs, making it the perfect solution for solar plant upgrades.

3. Smart Peak-Valley Arbitrage & Cost Optimization

Managed by an intelligent EMS, the system automatically charges during hours of surplus solar generation or low grid tariffs and discharges during peak-rate periods. This targeted "peak shaving and tariff arbitrage" directly slashes the factory's electricity expenses.

4. Highly Integrated & Plug-and-Play Design

The Dawnice All-In-One cabinet integrates the storage inverter, long-lifecycle LiFePO₄ batteries, advanced cooling thermal management, and an intelligent EMS. Factory-preconfigured, it requires minimal onsite wiring, ensuring safe, swift, and hassle-free commissioning.

5. Universal Compatibility with Tier-1 Inverters

This project stands as a testament to the seamless compatibility and stable communication between Dawnice C&I storage systems and global Tier-1 grid-tied inverters like Huawei, providing a proven, reliable template for the European market and beyond.

System Configuration

Component	Specification
Model	BS07-265-ES-X
Rated Power	125kW
Nominal Capacity	265kWh
Existing Solar	450kW PV + 450kW Huawei Inverters
Coupling	AC-Coupled Retrofit
Planned Expansion	6 Units in Parallel (Total 750kW / 1.59MWh)

Why Dawnice for Your European Solar Retrofit?

✅ AC-coupled retrofit — no DC-side rewiring required
✅ Tier-1 compatible — seamless integration with Huawei and other major inverters
✅ Scalable design — planned expansion to 6 parallel units
✅ Smart arbitrage — peak-valley tariff optimization
✅ 5+5 years warranty — long-term peace of mind

*Real installation case in Romania. System performance may vary based on local conditions.