A Comparative Study on the Efficiency and Economic Performance of Distributed Photovoltaics in Buildings Using Low-Voltage AC and Low-Voltage DC Power Distribution Systems

With the development of distributed photovoltaic and power electronics technology, buildings are using low-voltage Direct-Current (DC) distribution technology increasingly. In building projects using distributed photovoltaics, whether it is more appropriate to use low-voltage Alternating Current (AC) or low-voltage DC for power distribution has become a problem to be addressed. This study compares the cost and transmission efficiency through sorting out the bill of materials, market survey, and node data analysis for the identical functional target, based on typical low-voltage DC and low-voltage AC power distribution systems. The efficiency performance of the two systems and the main equipment required for each under the condition of accessing different photovoltaic capacities are summarized. Provide analysis methods and reference data for whether to use low-voltage DC power distribution or low-voltage AC power distribution in actual projects.