Report of National Power Reliability: Quarter 1, 2020

Operational Reliability of Generating Equipment

In the first quarter of 2020, the equivalent availability factors of coal-fired power units and conventional hydropower units of major power generation enterprises in China increased year-on-year. The average unplanned outage time of coal-fired units  decreased, and the average unplanned outage frequency of coal-fired units remained the same as last year; the unplanned outage frequency and unplanned outage time of conventional hydropower units increased year-on-year.

In the first quarter of 2020, the equivalent availability factors of coal-fired power units of major power generation enterprises reached 96.62%, an increase of 1.16 percentage points year-on-year. The average utilization hours of units were 933.31 hours, with a year-on-year decrease of 156.13 hours. The average frequency and time of unplanned outage of units were 0.10 times and 7.12 hours respectively, of which the  unplanned outage frequency was the same as last year, and the unplanned outage time decreased by 2.03 hours. The average planned outage time of units was 65.88 hours, with a year-on-year decrease of 20.99 hours.

Among them, the utilization hours of 1000MW units were 843.38 hours, a year-on-year decrease of 304.94 hours. The average outage frequency and time caused by the first three types of unplanned outage  were 0.04 times and 0.9 hours respectively, and the frequency of forced outages decreased by 0.01 times and the forced outage time increased by 0.1 hours year-on-year. Forced outages occurred 4 times, and the cumulative forced outage time was 89.1 hours.

In the first quarter of 2020, the equivalent availability factors of conventional hydropower units of major power generation enterprises were 91.71%, with a year-on-year increase of 2.37 percentage points. The average utilization hours of units were 687.29 hours, a year-on-year decrease of 63.99 hours; the average frequency and time of unplanned outages of units were 0.01 times and 0.19 hours, respectively, with the frequency of unplanned outages remained the same as last year, and the unplanned outage time decreased by 0.5 hours.

Among them, the utilization hours of 700MW conventional hydropower units were 735.02 hours, with a year-on-year decrease of 37.05 hours. No forced outage happened for the 700MW units, the average frequency and time of forced outage of which decreased by 0.02 times and 2.06 hours respectively.  Both of the forced outage frequency and the forced outage time of such units were 0 .

Operational Reliability of Power Transmission and Transformation Facilities

In the first quarter of 2020, the indicators of 13 types of transmission and transformation facilities with voltage level of 220 kV and above showed that their reliability performance were satisfactory. A total of 18999 transformers, 48782 circuit breakers and 834366km of overhead lines were incorporated into the power reliability statistics.

In the first quarter of 2020, the availability factor of transformers with voltage levels of 220 kV and above nationwide was 99.869%, a year-on-year increase of 0.02 percentage points. The forced outage rate was 0.106 times per 100 unit·year, down 0.021 times per 100 unit·year. The unplanned outage frequency and time were 24 times and 0.079 hours per unit·year respectively, up 13 times and 0.06 hours per unit·year.

The availability factor of the circuit breakers was 99.965%, with a year-on-year increase of 0.019 percentage points. The forced outage rate was 0.008 times per 100 unit·year, down 0.094 times per 100 unit·year. The frequency and time of unplanned outage were 4 times and 0.004 hours per unit·year, respectively, with a year-on-year decrease of 22 times and 0.01 hours per unit·year.

The availability factor of overhead lines was 99.737%, with a year-on-year increase of 0.162 percentage points. The forced outage rate was 0.029 times per 100 km per year, down 0.032 times per 100 km per year. The frequency and time of unplanned outage were 72 times and 0.126 hours per 100 km per year, respectively, with a decrease of 83 times and 0.514 hours per 100 km per year.

Reliability of power supply

In the first quarter of 2020, about 10.5122 million 10kV (20kV, 6kV) consumers were incorporated into the reliability statistics, with an increase of 796400 households over the same period of last year. The total length of 10 kV lines was 4.9619 million km, of which the insulation rate (insulation rate=length of insulated lines/total line length) of overhead lines was 29.43%, and the cable rate (cable rate=length of cable lines/ total line length) of lines was 18.42%. 

In the first quarter of 2020, the national average power supply reliability rate was 99.9321%, an increase of 0.0417 percentage points year-on-year; the average power outage time was 1.48 hours per household, a year-on-year decrease of 0.89 hours per household. Among them, the failure interruption time was 1 hour per household, a decrease of 0.10 hour per household year-on-year; the pre-scheduled outage time was 0.48 hours per household, a year-on-year decrease of 0.79 hour per household. The average frequency of power outages was 0.44 times/household, a decrease of 0.12 times/household year-on-year.

In the first quarter of 2020, the average power supply reliability rate of the urban area is 99.9756%, with a year-on-year increase of 0.0101 percentage points; the average power outage time is 0.53 hours per household, with a year-on-year decrease of 0.22 hours per household; and the average power failure frequency is 0.16 times per household, with a year-on-year decrease of 0.03 times per household. The average power supply reliability rate in rural areas was 99.9159%, with a year-on-year increase of 0.0530 percentage points; the average power outage time was 1.84 hours per household, with a year-on-year decrease of 1.12 hours per household; the average power failure frequency was 0.54 times per household, with a year-on-year decrease of 0.15 times per household.