What is the utilization hours of power generation equipment？

The utilization hours of power generation equipment is the number of operating hours of power generation equipment at rated power within a certain period of time (usually calculated as 1 year), that is, the ratio of power generation to rated installed capacity, reflecting the utilization rate of power generation equipment. The higher the utilization hours of power generation equipment, the higher the economic value created by the equipment. The utilization hours of power generation equipment are generally referred to as utilization hours, effective utilization hours, and power generation hours.

01. For thermal power (hydropower) units, the rated installed capacity is the sum of the rated power of all steam turbines (hydropower units). Therefore, as long as the power generation of thermal power (hydropower) units in a certain period of time is known, the utilization hours can be calculated (there is no unit expansion during the calculation period).

02. For wind power projects, the rated installed capacity is the sum of the rated capacities of all wind turbines. Similarly, as long as the power generation of the fan in a certain period of time is known, the utilization hours can be calculated.

03. For photovoltaic power generation projects, in the early years, everyone only paid attention to how many photovoltaic modules were installed (namely the nominal installed capacity), which refers to the sum of the nominal power of all photovoltaic modules. Until the NB/T 10394-2020 "Photovoltaic Power Generation System Performance Specification" released in 2020, the installed capacity and rated capacity of the photovoltaic power generation system were defined.

Installation capacity of PV modules refers to the sum of the nominal powers of PV modules installed in a PV power generation system, and the unit is peak watts (Wp).

Rated capacity refers to the sum of the rated active power of the inverters installed in the photovoltaic power generation system, and the unit is watts (W).

Therefore, the utilization hours of photovoltaic power generation projects should be calculated on the AC side. In fact, we should treat the photovoltaic power generation project as a whole, without considering how many photovoltaic modules are installed, just consider the rated capacity of the box inverter. On the other hand, assuming that the project has been connected to the grid at full capacity, the industry authorities do not know the installed capacity of the DC side of each power station when calculating the number of utilization hours, but calculates it based on the recorded capacity (AC side).

confusing concept

GB 50797-2012 "Code for Design of Photovoltaic Power Stations" proposes the annual peak sunshine hours of PV station, which refers to the annual total solar radiation received on the photovoltaic square array, converted into Hours under 1000W/m2 irradiance. Generally referred to as peak sunshine hours.

The peak sunshine hours describes the solar energy resources obtained (on the inclined surface of the module) from the perspective of energy source, and is equivalent to the standard of 1000W/m2, and does not reflect the concept of utilization, so the name "utilization" appears. , such as peak utilization hours and equivalent utilization hours are incorrect names, the editor believes that the actual meaning to be expressed is the utilization hours of power generation equipment.