What can it be used for?

This is a complete, three-phase solar energy storage package consisting of the FoxESS P3-15.0-SH hybrid inverter and an EP12 high-voltage (HV) battery. The hybrid inverter is the heart of the system: it manages solar panel output, battery charging and discharging, and grid connection—all in a single device. The EP12 is the energy storage component—this is where unused solar energy is stored, which you can then draw upon in the evening or during peak hours. Together, the two form a fully functional BESS (battery energy storage system) for homes or small businesses.

FoxESS 15 kW Hybrid HV 3-Phase + 12 kWh HV Heated Energy Storage Package

This is a complete, three-phase solar energy storage package consisting of the FoxESS P3-15.0-SH hybrid inverter and an EP12 high-voltage (HV) battery. The hybrid inverter is the heart of the system: it manages solar panel output, battery charging and discharging, and grid connection—all in a single device. The EP12 is the energy storage component—this is where unused solar energy is stored, which you can then draw upon in the evening or during peak hours. Together, the two form a fully functional BESS (battery energy storage system) for homes or small businesses.

What can it be used for?

Typical applications include larger households and smaller C&I (commercial and industrial) sites with three-phase power input and power requirements exceeding 10 kW. It’s a good choice where maximizing self-consumption is important: you generate and charge during the day, and cover your consumption from the battery in the evening. Thanks to the built-in EPS (uninterruptible power supply) output, designated loads continue to operate during a power outage. Since the battery can be expanded up to 4 units (up to ~46 kWh), the system is highly scalable should your needs grow in the future.

How does it work?

The inverter continuously monitors generation and consumption and decides where the energy should go: to the loads, to the battery, or to the grid (if permitted; otherwise, it curtails the excess). It uses three MPPT trackers, allowing it to handle strings of different orientations or sizes separately—which makes a big difference on more complex rooftops. The EP12 communicates with the inverter at high voltage (nominal 384 V) via a CAN bus, which provides higher discharge cycle efficiency than low-voltage solutions. The “heated” feature is key in winter: with the built-in heating function, the battery can be charged down to –25 °C, whereas without heating it would only go down to 0 °C—in Hungary and the region, this makes a real difference.

Technical and System-Level Benefits

On the PV side, the system can be over-paneled up to 30 kWp of installed capacity (max. 22.5 kW DC input), which helps maximize output in winter and on cloudy days. A 50 A charge/discharge current is available for the battery, and the EP12 provides ~10.4 kWh of usable energy (11.52 kWh nominal, at 90% DoD), with a discharge cycle efficiency of ≥95%. The entire system is IP65-rated and can be installed outdoors; monitoring is done via FoxCloud V2.0 from a smartphone or web browser. It also offers a wide range of communication options (Ethernet, RS485/EMS, Meter, Wi-Fi/LAN/Bluetooth, optional 4G, DRM, SG Ready), making it easy to integrate into an energy management system or smart home.

Differences

The P3-S family ranges from 5 to 15 kW; this package features the top-of-the-line 15 kW model, which, unlike the 12 and 15 kW versions, is fan-cooled (the smaller models are passively cooled). The high-voltage EP12 offers better efficiency and simpler wiring at higher power output compared to low-voltage (LV) batteries. If power consumption is lower or the input is single-phase, a smaller P3-S and fewer batteries may suffice—the 15 kW + 12 kWh configuration is specifically designed to meet more demanding requirements.

Important to know

One EP12 unit provides ~10.4 kWh, which may be insufficient for the 15 kW inverter if you want to cover longer backup times or high evening power consumption—in such cases, it’s advisable to plan for two units from the start. The heating function must be activated, and charging in winter results in additional power consumption. This is a good choice if you’re looking for a three-phase, expandable system suitable for outdoor installation and if winter operation is a priority.

SOLARKIT Reviews

We recommend this package to customers with a three-phase connection who are planning a larger PV system exceeding 10 kW—such as larger single-family homes, small workshops, or offices. The 15 kW inverter and the generous PV oversizing handle winter and cloudy-day generation well, and the EP12’s heated design ensures it keeps running even during Hungarian winters. Our realistic recommendation: start with at least two EP12 units (~20 kWh) if your goal is to maximize self-consumption and cover evening peak demand—a single unit is sufficient for entry-level storage. Those who plan to expand later will be well-served, as the system is scalable up to 46 kWh without needing to replace the inverter.