Sofar Solar Mono 3 kW Hybrid Inverter – ESI-3K-S1

Sofar Solar ESI 3kVA: Guaranteed reliability and performance

What this inverter actually does

The Sofar ESI 3K-S1 performs three functions continuously:

• It converts the energy from your solar panels (direct current) into electricity that can be used in your home (230 V AC), with a maximum efficiency of 97.7%
• It stores surplus energy in a Sofar BTS high-voltage battery for use in the evening or at night
• It automaticallyswitches to the battery in the event of a grid outage within 10 ms, with no noticeable interruption to your appliances

With a system comprising 6 to 8 solar panels (3 to 4 kWp) and a 5 to 10 kWh battery, a small household can achieve 55 to 70% self-consumption, representing an estimated saving of between €400 and €700 per year on your electricity bill, depending on your consumption profile and local tariff.

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Who is this 3 kW model for?

The ESI-3K-S1 is the right choice if you fit one of these profiles:

Small household or flat (1 to 3 people, 40 to 80 m²)
Annual consumption under 3,000 kWh — the 3 kW model perfectly covers the needs for lighting, refrigeration, television, computers and small electric water heaters.

First step into solar with a small budget
This is the most affordable entry-level option in the ESI Sofar range. Start with 6 panels and a battery, then upgrade later without changing the inverter.

Second home or holiday home
The inverter automatically manages generation and storage, even when you’re away. Remote monitoring via SolarMan Smart.

Tenant with landlord’s consent
Lighter installation, fewer panels, lower investment — ideal for a simple setup on a small south-facing roof or balcony.

High-voltage battery: modern and scalable architecture

Like the entire ESI Sofar range, the 3K-S1 works with the Sofar BTS 5K high-voltage battery system (400 V LiFePO4):

• Start with 1 BTS 5Kmodule (5.12 kWh) — enough to cover a full night’s energy needs for a small household
• Add up to 6 modules over time to reach 30.72 kWh — without changing the inverter
• CATL LiFePO4 cells: safe technology, long service life, BMS integrated into each module
• Max. charge/discharge current: 20 A — suitable for the inverter’s 3 kW power rating
• 400 V high-voltage system: better conversion efficiency and simplified wiring compared to 48 V systems

Advanced features

• 5 operating modes: priority self-consumption, off-peak hours, full sell-back, battery reserve, off-grid standalone
• AC Coupling: integrate an existing grid-connected inverter to charge the Sofar battery without replacing everything
• OTA updates: remote software updates, without physical intervention
• Compatible with CHINT DDSU666 meter: accurate monitoring of grid injection/withdrawal

Installation: what you need to know

Installation must be carried out by a qualified electrician for grid connection. Key points:

This model can operate without a battery from the moment of installation — add one when your budget allows

The main circuit breaker must be rated for 3 kW single-phase (minimum 16 A)

The battery cabling is rated for 20 A — standard cable cross-section is sufficient

Set up viathe built-in display or the SolarMan Smart app in just a few minutes

Sofar PowerAll

SolarMan Smart

SofarSolar is redefining the future of energy with smart inverters. Equipped with advanced monitoring features, our inverters come with a WiFi Stick as standard, paving the way for seamless connectivity. Choose your path to efficiency with options such as Ethernet, GPRS or LTE dongles. Transform every installation into a digital symphony, where solar power becomes a connected, smart and sustainable experience. SofarSolar, your partner for smarter and brighter energy.

Apple Store - Solarman Smart

Android - Google Play - Solarman Smart

Setup steps:

1. After launching the app, register as a new user or enter your current SOLARMAN login details.
2. Create a new system and enter the system data.
3. Scan the barcode on the logger stick to assign an inverter to the system.
4. Go to the newly created system to configure the logger stick (device/logger).
5. Press the button on the WiFi dongle for 1 second to activate the dongle’s WPS mode so that the smartphone can connect to the WiFi dongle.
6. Now select your local WiFi network for internet access and enter your WiFi password.
7. The WiFi dongle is now configured with the access details.