SolarEdge Nexis – a three-phase PV system with energy storage

SolarEdge Nexis is a solution that combines an inverter and a modular energy storage system into a single system. The design is intended for both new installations and the retrofitting of existing systems, and it can work with solutions connected on either the DC or AC side.

The SolarEdge Nexis inverter covers a power range of 8–20 kW, while the energy storage system can have a capacity ranging from 5 to 19.6 kWh per stack. The system supports up to four stacks, providing a total storage capacity of up to 78.4 kWh.

SolarEdge Nexis 8–20 kW Inverter

The Nexis inverter is designed to support installations with various power levels. The range covers units from 8 to 20 kW.

SolarEdge also highlights the inverter’s high efficiency at low power levels. The design utilizes SiC (silicon carbide) technology, which is intended to support high inverter efficiency under both high and low loads.

The unit uses active cooling and heat dissipation, and according to the manufacturer’s documentation, the fanless design enables virtually silent operation.

The inverter can be installed indoors or outdoors.

Solutions to Simplify Installation and Commissioning

The SolarEdge Nexis was also designed to simplify system installation and commissioning.

The inverter uses:

• a single part number for different power variants of the device,
• cabling that allows for installation without opening the enclosure,
• the option for indoor or outdoor installation,
• commissioning via the SolarEdge Go app.

The energy storage system uses the Simple-Click™ solution, which allows consecutive modules to be stacked. Individual blocks are positioned and locked into place, and then the entire stack can be mounted on the wall.

SolarEdge Nexis Inverter Safety

One of the areas of development in the Nexis system is installation safety. The inverter features arc-fault circuit interrupter ( AFCI) protection compliant with the IEC 63027 standard.

SolarEdge’s materials also highlight the SolarEdge Sense Connect solution, which operates at the power optimizer connector level.

The system also utilizes SafeDC™ and a remote shutdown function.

System Cybersecurity

The manufacturer also highlights cybersecurity solutions, including:

• encrypted data transfer,
• a unique default password available to a certified SolarEdge installer,
• a built-in security agent,
• a secure boot mechanism,
• compliance with cybersecurity standards, including the European NIS2 Directive.

SolarEdge Nexis Modular Energy Storage System

The Nexis energy storage system is designed as a modular and scalable solution. A single stack can have a capacity ranging from 5 to 19.6 kWh, and up to four stacks can be connected to a single inverter, providing a total capacity of up to 78.4 kWh.

The same energy storage system can be used in both single-phase and three-phase applications.

The system also provides emergency power for an entire home with a capacity of up to 20 kW.

Flexible Energy Storage Configuration

A single energy storage stack can consist of 1–4 Battery Blocks. Each block is 194 mm deep and weighs 55 kg.

The energy storage system can be set up as a freestanding or wall-mounted unit and can be installed indoors or outdoors.

The maximum charging power of the energy storage system is 28 kW.

Independent management of battery modules

SolarEdge Nexis uses a built-in energy storage optimizer, which allows each Battery Block to be managed independently.

According to the manufacturer, this solution allows the storage system to continue operating even if one of the battery modules fails.

The system also allows for the integration of previously used and new modules through automatic recalibration. The manufacturer also highlights improved temperature management for individual blocks.

Energy Storage Operation Across a Wide Temperature Range

The SolarEdge Nexis energy storage system is designed to operate at temperatures ranging from –20°C to +55°C.

The design also incorporates heating films to support the device’s operation at low temperatures.

The manufacturer also highlights the system’s quiet operation, which is important for installation in residential spaces.

Multi-level safety features of the energy storage system

The energy storage system uses lithium iron phosphate (LFP) cells.

SolarEdge describes the battery’s safety features across several levels. ThermoShield™ technology protects individual cells and limits the propagation of thermal runaway between them. The solution meets the requirements of the UL 9540A standard.

At the Battery Block level, a set of temperature sensors monitors individual modules, and the Always-On design ensures the storage system remains operational even if one of the blocks malfunctions.

Protection at the stack level includes a design resistant to thermal runaway propagation, as well as protection against dust and water.

Energy Storage and Dynamic Tariffs

SolarEdge also highlights the possibility of using AI-based operating modes for the energy storage system.

The system can make decisions regarding the use of solar energy, its storage, and drawing power from the grid. This feature was developed, among other things, with dynamic rates in mind.

SolarEdge Nexis as an Integrated PV and Energy Storage System

SolarEdge Nexis combines an 8–20 kW inverter with a modular energy storage system scalable from 5 to 78.4 kWh.

The system includes solutions for installation, safety, emergency power supply, independent battery module management, and operation across a wide temperature range.

The ability to use Nexis in both new installations and retrofits of existing systems allows the solution to be deployed in various configurations of photovoltaic systems with energy storage.