As Residential Energy Storage Demand Rises, All-in-One Units Emerge

Diverse Scenarios & Stable Demand

With diverse application scenarios and stable residential demand, energy storage applications can be categorized into three main scenes: generation-side storage, transmission and distribution-side storage, and consumption-side storage.

Applications on the generation and transmission/distribution sides primarily revolve around the grid, where energy storage is commonly used for peak shaving, frequency regulation, integrating renewable energy sources, alleviating grid congestion, and delaying the expansion and upgrade of transmission and distribution equipment.

Consumption-side scenarios typically involve households, businesses, and public institutions, where energy storage systems are mainly used for self-consumption of electricity, peak/off-peak price arbitrage, capacity fee management, and enhancing power supply reliability. According to BNEF statistics, residential demand accounts for roughly 20%-30% of global energy storage applications, significantly higher than industrial and commercial sectors.

Profit Models for Residential Energy Storage

In conjunction with photovoltaics (PV), increasing self-consumption ratio, and peak/off-peak price arbitrage. Residential energy storage is usually paired with rooftop PV systems, and currently, there are three main profit models:

1. Self-consumption: Before the phase-out of feed-in tariffs (FIT), FIT electricity prices were higher than residential electricity prices, incentivizing rooftop PV installations with "benchmark prices, full-grid access." As residential electricity prices rise and FIT subsidies taper off, overseas rooftop PV users are turning to energy storage to achieve higher self-consumption ratios.

2. Peak/off-peak arbitrage: Time-of-use pricing mechanisms are implemented in regions like California, Australia, major European countries, China, etc. Under this mechanism, energy storage systems charge during off-peak periods at night and discharge during peak daytime periods, leveraging price differentials to save on electricity costs.

3. Virtual power plant (VPP): This model involves integrating distributed energy storage systems into a single platform managed by energy management software. It analyzes, controls, and optimizes the operation of distributed energy storage systems scattered across user premises, participating in grid services to generate revenue.

All-in-One Units Utilize Direct Current Coupling for High Comprehensive Efficiency

Currently, for various household energy storage demands, household energy storage systems can be mainly categorized into integrated PV storage units (all-in-one units) and split energy storage units.

All-in-one units integrate PV inverters and bidirectional inverters, forming a single integrated system internally. The integrated mode typically utilizes direct current coupling, enabling plug-and-play functionality and realizing an integrated "PV + storage" solution, suitable for synchronously installing incremental household PV and storage systems.

On the other hand, split energy storage units are suitable for existing household PV systems and typically utilize alternating current coupling internally, facilitating connection with existing PV inverters.

Under the daytime generation and nighttime consumption model, direct current coupling mode exhibits significantly higher efficiency compared to alternating current coupling mode and aligns with the electricity consumption habits of most households. Their efficiencies are approximately 95% and 90%, respectively.