Innovative DC Coupling Architecture Transforms Solar Storage Systems: Sige New Energy Unveils Solutions at ESIE Energy Expo

On April 10, the 13th International Energy Storage Summit and Exhibition (ESIE 2025) commenced at the Capital International Exhibition Center. Sige New Energy made a significant appearance, showcasing its fully modular photovoltaic (PV) and energy storage integration solutions. This presentation highlighted the company’s advantages in PV-storage integration, high integration, flexible deployment, and AI intelligence, supporting the transition of new energy towards a high-quality development phase.

As the pricing of new energy enters a fully market-driven phase, the energy storage industry is evolving from a traditional supportive infrastructure to a crucial component of the new power system. This shift positions energy storage as a vital force for ensuring energy security and promoting low-carbon transformation. Sige New Energy has keenly recognized this opportunity and is advancing intelligent PV-storage integration systems across all scenarios, providing robust support for achieving carbon neutrality targets. The Sige Zero Carbon Park solution includes a series of commercial and industrial inverters (50kW-125kW) and modular energy storage systems, applicable in various settings such as industrial parks, commercial centers, data centers, and ground installations. The inverters are designed with reserved energy storage interfaces, allowing for easy adaptation to pure PV, pure storage, or a combination of both, enabling users to flexibly configure according to their actual needs.

With electricity prices undergoing market-driven fluctuations, the value of energy storage is being reassessed. The volatility of new energy prices will significantly increase, making the regulation capabilities and intelligence of energy storage systems increasingly crucial. The Sige commercial PV-storage system supports a “charge and discharge as needed” function, featuring an in-house developed Energy Management System (EMS) and Battery Management System (BMS). Combined with AI applications, this technology enables millisecond-level data collection and response, automatically adjusting charge and discharge strategies based on real-time electricity prices and load changes. When prices dip, the system prioritizes energy storage; conversely, during peak prices, it prioritizes discharging to supply loads or feed back into the grid, helping users implement economic strategies of “buy low, use high” or “buy low, sell high,” significantly enhancing storage returns.

The Sige Zero Carbon Park utilizes a fully modular design, greatly facilitating the maintenance of spare parts and lifecycle management for customer stations. Each module has a capacity of 12kWh, supporting flexible configurations from 50kWh to hundreds of megawatt-hours tailored to user storage needs. The commercial inverters have reserved energy storage interfaces, allowing users to install PV first and then storage, or vice versa, effectively reducing initial investment and operational costs while unleashing the potential value of energy storage in a market-driven electricity landscape.

The ability to consume photovoltaic energy has become a key factor for profitability. The Sige Zero Carbon Park can automatically adjust its storage strategy based on current electricity supply and demand: when PV generation is abundant, excess energy is stored in batteries; when demand exceeds PV capacity, battery power is called upon to supply the load. This dynamic management model maximizes the utilization of PV generation, significantly increases self-consumption rates, reduces dependence on the grid, and effectively cuts electricity costs.

Furthermore, the innovative direct current (DC) coupling architecture introduced by Sige Zero Carbon Park allows for a matching ratio of up to 2. During peak sunlight hours, excess DC energy beyond the load or inverter output capability can be efficiently stored in batteries without requiring AC conversion. This significantly enhances overall system efficiency and energy utilization, greatly increasing the proportion of green electricity for enterprises.

Additionally, the DC coupling architecture enhances the cycle efficiency of the PV-storage system. Energy only needs to be converted in a DC state during charging, avoiding extra losses from AC inversion and subsequent DC conversion, thus minimizing energy losses from multiple current and voltage conversions, potentially improving system round-trip efficiency (RTE) by up to 2%. In large grid-connected projects, the DC coupling system is simpler compared to AC systems, saving on energy conversion devices and medium-voltage cabinets. Fewer components not only mean lower initial investment costs but also reduced maintenance workload, leading to higher returns for customers.

In the electricity spot market environment, where market prices and load demands fluctuate rapidly, energy storage systems must possess high flexibility and responsiveness to fully realize their value. The Sige Zero Carbon Park PV-storage system deeply integrates artificial intelligence with big data analysis and machine learning algorithms, enabling the system to manage PV generation, energy storage, and grid interaction flexibly based on price fluctuations, weather changes, and load variations. It automatically optimizes battery charge and discharge timing, generating real-time optimal energy solutions to minimize electricity costs and enhance the operational efficiency of energy storage systems. This adaptability allows for seamless integration with dynamic pricing, virtual power plants, and complex energy trading scenarios, providing users with the most intelligent energy experience.

Ensuring system safety is paramount. The Sige energy storage system incorporates battery pack-level safety protections, including sensors, active fire modules, high-temperature insulation mats, insulated thermal layers, explosion-proof valves, and smoke detection devices. This six-layer battery safety protection system detects thermal runaway in battery cells and responds within seconds, significantly faster than traditional solutions, which can be over a minute late in responding to thermal events. Furthermore, an independent fire protection device is installed for every 12kWh, providing comprehensive safety for the system. In contrast, conventional energy storage systems can allow fire incidents to spread throughout the entire system, leading to broader impacts and slower fire protection responses.

The maintenance-free and modular design of the Sige system ensures stability and reliability. It features a fully sealed design rated at IP66, while traditional solutions typically reach only IP55, making them more prone to damage and requiring monthly checks and biannual replacements of parts. Additionally, the modular design allows for module replacement in just 2 hours, significantly improving reliability compared to traditional containerized energy storage systems, which can take over two days for repairs. The Sige solution also offers comprehensive monitoring, from automatic device diagnostics to remote inspections, further optimizing intelligent operation and maintenance management.

The installation efficiency of Sige PV-storage solutions is significantly better than traditional methods. Thanks to the modular design and stackable installation, the installation process is greatly simplified, requiring no cranes or poured foundations, allowing for the installation of a complete system in less than one hour. The pioneering fully networked communication system, which dramatically increases communication speeds compared to traditional RS485 communications, supports device self-recognition and system self-networking, completing system debugging in just 15 minutes. By contrast, traditional systems require specialized installation equipment, taking 8 hours per system, substantially increasing user wait times and installation costs.

For residential and small commercial applications, the Sige Zero Carbon Home solution integrates PV inverters, energy storage converters, energy storage batteries, DC charging modules, and energy management systems, introducing the SigenStor integrated PV-storage charger. This system supports rapid switching between grid-connected and off-grid modes, providing stable power supply during outages. With efficient energy management, advanced safety features, and innovative AI integration, it has garnered high recognition from exhibition attendees. The company has stated its commitment to continue advancing technological innovation and product optimization, expanding the boundaries of PV-storage integration, and providing more efficient and reliable green energy solutions to users across various industries, contributing to the construction of a new power system that accelerates the energy transition towards low-carbon, efficient, and intelligent solutions.