Acrel Residential PV Supporting Solutions

Residential solar PV systems are small-scale photovoltaic (PV) power generation systems installedon rooftops, balconies, or other areas of a home to supply electricity to the household. They can begrid-connected or paired with energy storage for off-grid emergency use, making them a mainstream

solution for home energy self-sufficiency.

Main components of residential solar PV systems: Solar panels + Inverter

Optional Configurations:

o Energy Storage Battery: Stores excess electricity for peak-valley arbitrage or emergency power outages.

o Monitoring Equipment: Such as Acrel ADL200W/ADL400W meters, used to measure electricity generation and consumption.

o Anti-Backflow Device: Mandatory in some countries to prevent excess electricity from flowing back into the grid.

• Grid-connected: The system is connected to the power grid. Unused electricity generated by the photovoltaic system can be sold back to the grid, and insufficient electricity can be purchased from the grid (e.g., a balcony micro-storage system; unused electricity generated during

 the day is fed back to the grid, and supplemented by electricity from the grid at night).

• Off-grid: For example, during a power outage, the system relies on its own photovoltaic system and batteries for power, without using grid electricity (like "off-grid loads" in a residential photovoltaic-storage system; refrigerators and lights can still be used during a power outage).

The core customers for overseas residential photovoltaic systems mainly fall into three categories:

1. Ordinary households: This is the largest customer group, commonly found in countries with high electricity prices and abundant sunshine. Their core need is to reduce electricity bills, and some users pursue energy self-sufficiency.

2. Small farms/manor owners: In addition to meeting household electricity needs, they also need to power agricultural loads such as irrigation pumps and greenhouse equipment, often requiring multiple inverters and energy storage systems.

3. Housing Developers / Property Management Companies

In some European and American countries, developers include residential solar PV systems as part of the high-end interior design, increasing the property's premium; property management companies, on the other hand, uniformly install balcony solar PV systems in apartment buildings to attract tenants.

Our equipment's role in residential solar PV systems is reverse current monitoring, primarily monitoring the current/power at the grid connection point.

Core issues facing residential PV systems:

1. Low power generation efficiency and unclear returns: Residential PV systems often experience reduced power generation efficiency due to module shading and inverter failures, and users cannot accurately calculate power generation and electricity revenue.

Monitoring equipment can monitor the power generation of PV branches and grid interconnection in real time. The dual-loop function of the ADL200M/400M can also distinguish between direct PV power supply and energy storage charging and discharging data, 

helping users locate inefficient modules or faulty equipment, and accurately calculate the revenue from surplus electricity fed into the grid, avoiding revenue loss.

2. Poor grid connection compliance and potential fines (anti-backflow monitoring): Regions such as Europe and the United States mandate anti-backflow monitoring, and illegal grid connection can result in hefty fines.

Dangers of power backflow:

* Local grid overload: A large number of users simultaneously feeding back power into the grid can cause overload and overheating of distribution transformers, lines, and other equipment, accelerating aging and even causing damage.

* Voltage exceeding limits and power quality deterioration: Local grid voltage rises, exceeding the rated range (e.g., 230V±10%), causing damage to neighboring appliances. It may also introduce harmonic pollution.

Island effect: If a user's photovoltaic/energy storage system continues to operate and supply power to the local line during a grid outage, it can endanger the lives of electrical personnel performing maintenance.

The ADL200W/400W can monitor the grid-connected current in real time and, in conjunction with the inverter, achieve rapid current limiting to ensure grid compliance.

3. High operation and maintenance costs and difficulty in troubleshooting: Residential photovoltaic systems are scattered, making manual inspections costly and faults difficult to detect in a timely manner.

The ADL200W/ADL400W supports remote data upload via WIFI. Users and maintenance personnel can view the system's operating status in real time via mobile phone or platform. If voltage anomalies, metering deviations, or other problems occur, the system automatically 

pushes alarm information, enabling rapid fault location and significantly reducing operation and maintenance costs.

General Core Requirements (Required in All Countries)

1. Metering Accuracy Compliance

* As the basis for electricity bill settlement or subsidy calculation, the accuracy of the monitoring meter must reach Class 1 or higher.

* It must support bidirectional metering, simultaneously monitoring photovoltaic power generation, grid-purchased electricity, and surplus electricity fed into the grid, meeting the statistical requirements of net metering policies.

2. Compliance Certification Required

* Must pass the mandatory certifications of the local market, such as CE certification in the EU, UL certification in the US, SAA certification in Australia, and JET certification in Japan.

* Equipment involving grid-connected data upload must comply with the communication protocol standards of the grid side to avoid data format incompatibility.

3. Communication Function Adaptation

* Support mainstream communication methods: For home scenarios, prioritize WIFI/Bluetooth for convenient viewing via mobile APP; large residential or multi-inverter systems must support RS485/Modbus for multi-device data aggregation.

* Some countries require monitoring data to be uploaded to a government-designated platform; the equipment must support the corresponding cloud protocol.

4. Strong environmental adaptability: Household monitoring equipment is mostly installed in distribution boxes and must meet IP20 or higher protection level, withstand operating temperatures of -20℃ to 60℃, and adapt to temperature differences in outdoor distribution boxes.