“What else is essential to a photovoltaic plant, apart from the rate of generation and the high yield?”

“Clear!”

From large-scale ground power plants to today's distributed small-scale power plants, PV is getting closer and closer to people's lives. The 17-year-old distributed PV explosion also marks the official development of PV into a viable life-style products.

The efficiency and profitability of power plants is a concern for every photovoltaic owner/investor, but there is also a fundamental but easily overlooked concern: safety.

Unlike large ground-mounted power plants, distributed photovoltaic systems are installed on homes, factories, warehouses, commercial buildings, schools, and municipal buildings. These buildings may be densely occupied, contain precision equipment, or store flammable materials. Their photovoltaic systems therefore face stricter safety requirements: they must not disrupt the buildings’ existing uses or create hazards for people, operations, or stored materials.

For safety, let us first look at the national regulations:

·In the United States, the Fire Safety Association revised its National Electrical Code to state: “In an emergency, the DC voltage of a photovoltaic system should not exceed 80 volts when its AC connection is disconnected.”

·In Italy, firefighters are not allowed to extinguish a fire in a building with a voltage.

·Germany, the first to implement the VDE fire safety standards, clearly in photovoltaic systems between the inverter and the need to add a DC power cut-off device.

·In Australia, according to Ove R11-1:2013, there must be a circuit breaker near the assembly.

High-voltage direct current is a major safety concern in photovoltaic plants worldwide. It can complicate emergency response and cause fires through DC arcing. For this reason, microinverters with a DC-side voltage of about 40 V have become popular in some overseas markets.

The safety benefits of microinverters extend beyond their 40V low voltage. A photovoltaic power plant is designed for an operating life of 25 years. Consistent generation over 25 years requires quality, safety, operation, and maintenance. Microinverters provide module-level monitoring, allowing each module’s operating status to be observed in real time throughout the 25-year operating period. If a safety fault occurs, the monitoring platform provides prompt feedback, improving system safety while supporting power-generation efficiency.