According to the information in Fig. 3, the theoretical utilization hours of wind power and PV power can be calculated as 1913 hours and 1550 hours, respectively.
Almost the same amount of annual generation utilization hours would be allocated to power units within the same category, without considering the differences in efficiency among power units.
However, the annual utilization hours of the peaking demand-oriented generation and transmission equipment is small and the average generation cost of the peaking unit is high.
kern-0pt} {H_{i} }}} right| le Delta Hquad forall i in N (3)where h i,t is the actual utilization hours of unit i at day t; H i is the approved annual utilization hours for unit i; ΔH is the relative deviation limit; T is the number of days in one year; N is the number of units to be dispatched.
Since the annual utilization hours of power units are determined by authorities and power dispatching centers are responsible for dispatching power units using a consistent process [24], it is essentially a planned dispatch.
However, the annual wind power equipment utilization hours were 1728 h, which dropped by 172 h over the previous year, because the development of the national transmission grid has not kept up with the development of wind power.
The installed capacity of coal-fired units accounts for 74.6% of the total capacity of thermal power units and the annual utilization hours of coal-fired units are more than those of gas-fired units.
For simplicity, this paper does not consider load prediction deviations, and the simulation program will assign the annual utilization hours to the daily generating plan according to the daily load rate, in order to meet the "Open, Just and Fair" principles.
sumnolimits_{t = 1}^{{T_{x} }} {sumlimits_{i in G} {left( {N_{ti} cdot W_{i} } right)} } ge Dm_{t} cdot left( {1 + R} right) (11 where T ti is the annual utilization hours for units on platform i in year t; Em t the predicted electricity demand; and E the percentage of electricity reserve.
Under PD, based on the forecast annual load, the corresponding authorities approve the annual utilization hours for each generation category, which will be successively decomposed into the monthly generating plan and the daily generating plan combined with appropriate adjustments [28], which can be described by (3).
