Anhui's first demonstration project for distributed new energy DC cluster consumption put into operation

Recently, Anhui's first distributed new energy DC cluster consumption demonstration project was officially launched in Dawan village, Jinzhai county, Lu'an city. The project has successfully integrated and accommodated diverse elements, including 428 kW of distributed photovoltaic power, a 150 kWh energy storage system, 60 kW charging stations, and conventional agricultural loads.

In order to reduce the high proportion of distributed photovoltaic spillover power in Dawan village, a "Red Tourism" area, and enhance the efficiency of new energy power generation utilization, the Anhui Electric Power Economic Research Institute of the State Grid, in collaboration with the Jinzhai County Power Supply Company and other entities, initially established a joint research and application team encompassing industry, academia, and research. This team has been continuously engaged in technical research, focusing on flexible networking of AC/DC hybrid distribution grids and coordinated scheduling of source, network, load, and storage. This effort aims to facilitate the research and implementation of demonstration project schemes.

Based on the trends in new energy power generation and electricity load curves, the research team categorized the five substations within the demonstration area into three clusters: overflow, self-balancing, and load-bearing. Taking into account the current state of the regional power grid, as well as the typical characteristics of distributed generation and load, they constructed the first AC/DC hybrid distribution network based on a "local-cluster-inter-cluster-remote" consumption model. This model enabled the transfer of excess power from overflow substations to load-bearing substations via DC lines during the day, when new energy generation was abundant, thus preventing photovoltaic power backflow and excessive voltage at the consumer end. Simultaneously, load balancing within the substations was achieved through load transfer between clusters. At night, excess power was directed to areas with insufficient load via DC lines, significantly enhancing power supply reliability and ensuring safe and stable power delivery for the "Red Tourism" loads in the demonstration area.

After the project is put into operation, the utilization efficiency of distributed photovoltaic power generation in the demonstration area can be increased by over 6 percent. With an annual increase of more than 10,000 kWh in distributed photovoltaic power generation, this can reduce carbon emissions by about 8.5 tons. Additionally, the comprehensive line loss rate in the station area has fallen by about 25 percent, significantly enhancing the consumption level of distributed photovoltaic power in the village. This provides a referable and replicable experience for reducing rural distributed photovoltaic overflow power.