Distributed photovoltaic (PV) power stations refer to small-scale power generation systems located near users, typically connected to a power grid with a voltage level of 10 kV or lower. The small-scale residential rooftop PV power stations we commonly see are examples of distributed PV power stations.
Distributed photovoltaic power stations are a new type of power generation and comprehensive energy utilization method with broad development prospects. They advocate the principles of local power generation, local grid connection, local conversion, and local use. This not only effectively increases the power generation of photovoltaic power stations of the same scale, but also effectively solves the problem of power loss during voltage boosting and long-distance transmission.
Advantages of distributed photovoltaic power stations
1. Relatively small output power, scale can be flexibly adjusted.
Distributed photovoltaic (PV) power generation projects have capacities ranging from several kilowatts to several megawatts, with output power far less than that of large-scale ground-mounted PV power plants. The scale can be adjusted through modular design of PV power generation. The capacity of the PV system can be adjusted according to factors such as roof area and construction conditions. The installation method is relatively flexible and suitable for decentralized construction in areas with concentrated energy consumption.
2. The project generates minimal pollution and offers significant environmental benefits.
Like other new energy projects, distributed photovoltaic power generation produces no pollution or noise during the power generation process, and does not pollute the air or water. It is suitable for development in livable cities and remote areas, and is also one of the effective means to prevent smog and achieve energy conservation and emission reduction goals.
3. Power generation and consumption coexist, resulting in less loss on transmission lines.
Large-scale ground-mounted photovoltaic (PV) power generation involves stepping up the voltage and connecting to the transmission grid, participating solely as a power source in grid operation. Distributed PV power generation, on the other hand, connects to the distribution network, generating and using the power directly, with most of it being consumed locally. Because it doesn't require long-distance transmission, there are no line losses, and it's directly consumed within the distribution network, resulting in generally higher utilization rates than ground-mounted PV power plants.
4. Located near load centers, with minimal impact on the power grid.
Distributed photovoltaic systems are typically located in load centers in central and eastern China, selling electricity directly to large industrial and commercial users and residences. They do not require long-distance transmission, saving grid costs. Their scale is generally smaller than that of ground-mounted grid-connected photovoltaic power plants, and their impact on grid frequency and voltage fluctuations is limited.
5. Saves land resources and development costs
Distributed photovoltaic (PV) power station projects do not require development on contiguous land, thus effectively saving land resources and improving the utilization efficiency of idle rooftops and factory buildings. Furthermore, given the increasing electricity demand from large industrial and commercial enterprises, owners are motivated to build distributed PV power stations, and the development costs are generally lower than those of large grid-connected PV power stations.
Disadvantages of distributed photovoltaic power stations
1. With a large number of participants, uncertainties have increased.
Distributed photovoltaic power stations involve a large number of rooftop owners and energy-consuming enterprises. Due to their decentralized and diverse nature, the resulting business models are also different during project implementation. They generally have more uncertainties than ground-mounted photovoltaic power station projects. For example, some projects may encounter uncertainties such as rooftop ownership transfer, force majeure, and contract risks. Therefore, the development and operation of distributed photovoltaic power stations are more complex than large-scale grid-connected photovoltaic power stations.
2. Low efficiency in electricity bill settlement.
Currently, electricity bill settlement for distributed photovoltaic power stations largely adopts the energy performance contracting model, which lacks guarantees for collection and performance. The timeliness and stability of electricity bill collection are affected by the operating conditions of electricity-consuming enterprises, and this is a concern.
