HIGH-PRECISION SOLAR RESOURCE ASSESSMENT METHOD BASED ON DOWNSCALING METHOD FOR COMPLEX TERRAIN

Abstract

A high-precision solar resource assessment method based on a downscaling method for complex terrain includes steps as follows. Step (1): an average climatic field is calculated based on monitoring data of sunshine durations, climatic field interpolation results are obtained based on the average climatic field, and a climatic field is created. Step (2): a difference between data of the sunshine durations and the climatic field is calculated, anomaly field interpolation results are obtained based on the difference, and an anomaly field is created. Step (3): the climatic field interpolation results and the anomaly field interpolation results are overlayed. Step (4): bias adjustment is performed on the high-precision sunshine duration interpolation results obtained in the step (3) based on the monitoring data of the sunshine durations to obtain final results. Step (5): daily solar radiation is estimated based on the sunshine durations and extraterrestrial solar radiation.

Claims

1. A high-precision solar resource assessment method based on a downscaling method for complex terrain, comprising: step (1), calculating an average climatic field based on monitoring data of sunshine durations, obtaining, based on the average climatic field, climatic field interpolation results, and creating a climatic field based on the climatic field interpolation results; step (2), calculating a difference between data of the sunshine durations and the climatic field, obtaining, based on the difference, anomaly field interpolation results, and creating an anomaly field based on the anomaly field interpolation results, comprising: performing, by using a thin-plate smoothing spline function with an elevation as a covariate, spatial interpolation on an anomaly value to obtain the anomaly field interpolation results, wherein a precision of the spatial interpolation is consistent with a precision required for solar resource assessment, and the difference between the data of the sunshine durations and the climatic field is the anomaly value; step (3), overlaying the climatic field interpolation results and the anomaly field interpolation results, comprising: overlaying the climatic field interpolation results and the anomaly field interpolation results with consistent spatial resolutions to obtain high-precision sunshine duration interpolation results; step (4), performing bias adjustment on the high-precision sunshine duration interpolation results obtained in the step (3) based on the monitoring data of the sunshine durations to obtain final results; step (5), estimating daily solar radiation based on the sunshine durations and extraterrestrial solar radiation, wherein a formula for estimating the daily solar radiation is expressed as follows: ${\mathrm{SR}}_{\mathrm{short}}=\left(0.25+\frac{{\mathrm{Hour}}_1}{2{\mathrm{Hour}}_2}\right).Math.{\mathrm{SR}}_{\mathrm{extra}}$ where SR.sub.short represents shortwave radiation, and the shortwave radiation is used to assess a solar resource, in units of mega joules per square meter (MJ/m.sup.2); SR.sub.extra represents the extraterrestrial solar radiation, in units of MJ/m.sup.2; Hour.sub.1represents an actual sunshine duration on a day, in units of hours (h); and Hour.sub.2 represents a maximum possible sunshine duration on a day, in units of h, and a formula of the maximum possible sunshine duration on the day is expressed as follows: ${\mathrm{Hour}}_2=\frac{24.Math.{\mathrm{Sundip}}_1}{}$ where Sundip.sub.1 represents a sunset hour angle, in units of radians (rad), and a formula of the sunset hour angle is expressed as follows: ${\mathrm{Sundip}}_1=\arccos \left(-\tan \left(\mathrm{Lat}\right).Math.\tan \left({\mathrm{Sundip}}_2\right)\right)$ where Lat represents a latitude, in units of rad; and Sundip.sub.2 represents a solar declination angle, in units of rad, and a formula of the solar declination angle is expressed as follows: ${\mathrm{Sundip}}_2=0.409.Math.\sin \left(2.Math..Math.\frac{{\mathrm{Date}}_1}{{\mathrm{Date}}_2}-1.39\right)$ where Date.sub.1 represents a day of a year, which is an ordinal number of the day in the year; and Date2 represents a total number of days of the year, which is 365 for a common year, or 366 for a leap year; and wherein a formula of the extraterrestrial solar radiation SR.sub.extra is expressed as follows: ${\mathrm{SR}}_{\mathrm{extra}}=118.08.Math.\frac{\mathrm{Distance}}{}.Math.\left({\mathrm{Sundip}}_1.Math.\sin \left(\mathrm{Lat}\right).Math.\sin \left({\mathrm{Sundip}}_2\right)+\cos \left(\mathrm{Lat}\right).Math.\cos \left({\mathrm{Sundip}}_2\right).Math.\sin \left({\mathrm{Sundip}}_2\right)\right)$ where SR.sub.extra represents the extraterrestrial solar radiation, in units of MJ/m.sup.2; Lat represents a latitude, in units of rad; Sundip.sub.1 represents a sunset hour angle, in units of rad; Sundip.sub.2 represents a solar declination angle, in units of rad; and Distance represents a relative Sun-Earth distance, in units of astronomical units (AU), and a formula of the relative Sun-Earth distance is expressed as follows: $\mathrm{Distance}=1+0.33.Math.\cos \left(\frac{2.Math..Math.{\mathrm{Date}}_1}{{\mathrm{Date}}_2}\right)$ where Date.sub.1 represents a day of a year, which is an ordinal number of the day in the year; and Date.sub.2 represents a total number of days of the year, which is 365 for a common year, or 366 for a leap year; and step (6), converting the daily solar radiation obtained from the step (5) as multi-scale cumulative solar radiation for years in a target region, and then performing, using the multi-scale cumulative solar radiation, solar energy resource assessment to obtain a solar energy resource result in the target region; in respond to the solar energy resource result exceeding a target energy demand in the target region, determining an optimal location of a solar power plant in the target region, then establishing the solar power plant in the optimal location; in respond to the solar energy resource result being less than the target energy demand in the target region, determining the optimal location of the solar power plant in the target region, and determining optimal system capacity of the solar power plant based on the solar energy resource result to ensure stable power supply during a period of scarce solar energy resources, then establishing the solar power plant with the optimal system capacity in the optimal location.

2. The high-precision solar resource assessment method based on the downscaling method for complex terrain as claimed in claim 1, wherein the step (1) comprises: performing, using the thin-plate smoothing spline function with the elevation as the covariate, spatial interpolation on the average climatic field to obtain the climatic field interpolation results, wherein the precision of the spatial interpolation on the average climatic field is consistent with the precision required for the solar resource assessment, the data of the sunshine durations for the climatic field is obtained from an average sunshine duration monitored over a period of thirty years, and the precision required for the solar resource assessment is in a range of 1 kilometer (km) to 25 km.

3. The high-precision solar resource assessment method based on the downscaling method for complex terrain as claimed in claim 1, wherein the step (4) comprises: performing, by using a distance cumulative distribution function method, the bias adjustment on the high-precision sunshine duration interpolation results and the anomaly field interpolation results.

4. A high-precision solar resource assessment method based on a downscaling method for complex terrain, comprising: step (1), calculating an average climatic field based on monitoring data of sunshine durations, obtaining, based on the average climatic field, climatic field interpolation results, and creating a climatic field based on the climatic field interpolation results; step (2), calculating a difference between data of the sunshine durations and the climatic field, obtaining, based on the difference, anomaly field interpolation results, and creating an anomaly field based on the anomaly field interpolation results, comprising: performing, by using a thin-plate smoothing spline function with an elevation as a covariate, spatial interpolation on an anomaly value to obtain the anomaly field interpolation results, wherein a precision of the spatial interpolation is consistent with a precision required for solar resource assessment, and the difference between the data of the sunshine durations and the climatic field is the anomaly value; step (3), overlaying the climatic field interpolation results and the anomaly field interpolation results, comprising: overlaying the climatic field interpolation results and the anomaly field interpolation results with consistent spatial resolutions to obtain high-precision sunshine duration interpolation results; step (4), performing bias adjustment on the high-precision sunshine duration interpolation results obtained in the step (3) based on the monitoring data of the sunshine durations to obtain final results; step (5), estimating daily solar radiation based on the sunshine durations and extraterrestrial solar radiation, wherein a formula for estimating the daily solar radiation is expressed as follows: ${\mathrm{SR}}_{\mathrm{short}}=\left(0.25+\frac{{\mathrm{Hour}}_1}{2{\mathrm{Hour}}_2}\right).Math.{\mathrm{SR}}_{\mathrm{extra}}$ where SR.sub.short represents shortwave radiation, and the shortwave radiation is used to assess a solar resource, in units of MJ/m.sup.2; SR.sub.extra represents the extraterrestrial solar radiation, in units of MJ/m.sup.2; Hour.sub.1 represents an actual sunshine duration on a day, in units of h; and Hour.sub.2 represents a maximum possible sunshine duration on a day, in units of h, and a formula of the maximum possible sunshine duration on the day is expressed as follows: ${\mathrm{Hour}}_2=\frac{24.Math.{\mathrm{Sundip}}_1}{}$ where Sundip.sub.1 represents a sunset hour angle, in units of rad, and a formula of the sunset hour angle is expressed as follows: ${\mathrm{Sundip}}_1=\arccos \left(-\tan \left(\mathrm{Lat}\right).Math.\tan \left({\mathrm{Sundip}}_2\right)\right)$ where Lat represents a latitude, in units of rad; and Sundip.sub.2 represents a solar declination angle, in units of rad, and a formula of the solar declination angle is expressed as follows: ${\mathrm{Sundip}}_2=0.409.Math.\sin \left(2.Math..Math.\frac{{\mathrm{Date}}_1}{{\mathrm{Date}}_2}-1.39\right)$ where Date.sub.1 represents a day of a year, which is an ordinal number of the day in the year; and Date.sub.2 represents a total number of days of the year, which is 365 for a common year, or 366 for a leap year; and wherein a formula of the extraterrestrial solar radiation SR.sub.extra is expressed as follows: ${\mathrm{SR}}_{\mathrm{extra}}=118.08.Math.\frac{\mathrm{Distance}}{}.Math.\left({\mathrm{Sundip}}_1.Math.\sin \left(\mathrm{Lat}\right).Math.\sin \left({\mathrm{Sundip}}_2\right)+\cos \left(\mathrm{Lat}\right).Math.\cos \left({\mathrm{Sundip}}_2\right).Math.\sin \left({\mathrm{Sundip}}_2\right)\right)$ where SR.sub.extra represents the extraterrestrial solar radiation, in units of MJ/m.sup.2; Lat represents a latitude, in units of rad; Sundip.sub.1 represents a sunset hour angle, in units of rad; Sundip.sub.2 represents a solar declination angle, in units of rad; and Distance represents a relative Sun-Earth distance, in units of AU, and a formula of the relative Sun-Earth distance is expressed as follows: $\mathrm{Distance}=1+0.33.Math.\cos \left(\frac{2.Math..Math.{\mathrm{Date}}_1}{{\mathrm{Date}}_2}\right)$ where Date.sub.1 represents a day of a year, which is an ordinal number of the day in the year; and Date.sub.2 represents a total number of days of the year, which is 365 for a common year, or 366 for a leap year; and step (6), converting the daily solar radiation obtained from the step (5) into multi-scale cumulative solar radiation for years in a target region, and then performing, using the multi-scale cumulative solar radiation, solar energy resource assessment to obtain a solar energy resource result in the target region; and in respond to the solar energy resource result exceeding a target energy demand in the target region, determining an optimal location of a solar power plant in the target region, and then establishing the solar power plant in the optimal location.

Description

BRIEF DESCRIPTION OF DRAWING

[0028] FIGURE illustrates a schematic flow chart of a high-precision solar resource assessment method based on a downscaling method for complex terrain according to an embodiment of the disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

[0029] The technical solution of the disclosure will be further explained in conjunction with the attached drawing.

[0030] As shown in FIGURE, a high-precision solar resource assessment method based on a downscaling method for complex terrain includes step (1) to step (5) as follows.

[0031] Step (1): an average climatic field is calculated based on monitoring data of sunshine durations, climatic field interpolation results are obtained based on the average climatic field, and a climatic field is created based on the climatic field interpolation results. Specifically, the spatial interpolation is performed on the average climatic field by using the thin-plate smoothing spline function with elevation as the covariate to obtain the climatic field interpolation results. Precision of the spatial interpolation on the average climatic field is consistent with precision required for the solar resource assessment, the monitoring data of the sunshine durations for the climatic field is obtained from daily average sunshine durations monitored over a period of thirty years (i.e., 30-year gridded sunshine duration average data), and the precision required for the solar resource assessment is in a range of 1 kilometer (km) to 25 km.

[0032] Step (2): a difference between the monitoring data of the sunshine durations and the climatic field is calculated, anomaly field interpolation results are obtained based on the difference, and an anomaly field is created based on the anomaly field interpolation results. Specifically, the spatial interpolation is performed on an anomaly value by using a thin-plate smoothing spline function with the elevation as a covariate to obtain the anomaly field interpolation results. The precision of a spatial interpolation is consistent with the precision required for the solar resource assessment, and the difference between the data of the sunshine durations and the climatic field is the anomaly value.

[0033] Step (3): the climatic field interpolation results and the anomaly field interpolation results are overlayed. Specifically, the climatic field interpolation results and the anomaly field interpolation results with consistent spatial resolutions are overlayed to obtain high-precision sunshine duration interpolation results.

[0034] Step (4): bias adjustment is performed on the high-precision sunshine duration interpolation results obtained in the step (3) based on the monitoring data of the sunshine durations to obtain final results. Specifically, the bias adjustment is performed on the high-precision sunshine duration interpolation results and the anomaly field interpolation results by using a distance cumulative distribution function method.

[0035] Step (5): daily solar radiation is estimated based on the sunshine durations and extraterrestrial solar radiation. Specifically, the step (5) includes a formula for estimating the daily solar radiation is expressed as follows:

[00007]$S{R}_{\mathrm{short}}=\left(0.25+\frac{{\mathrm{Hour}}_1}{2{\mathrm{Hour}}_2}\right).Math.{\mathrm{SR}}_{\mathrm{extra}}$

where SR.sub.short represents shortwave radiation, and the shortwave radiation is used to assess a solar resource, in units of mega joules per square meter (MJ/m.sup.2); SR.sub.extra represents the extraterrestrial solar radiation, in units of MJ/m.sup.2; Hour, represents an actual sunshine duration on a day, in units of hours (h); and Hour.sub.2 represents a maximum possible sunshine duration on a day, in units of h.

[0036] A formula of the maximum possible sunshine duration on the day is expressed as follows:

[00008]${\mathrm{Hour}}_2=\frac{24.Math.{\mathrm{Sundip}}_1}{}$

where Sundip.sub.1 represents a sunset hour angle, in units of radians (rad).

[0037] A formula of the sunset hour angle is expressed as follows:

[00009]${\mathrm{Sundip}}_1=\arccos \left(-\tan \left(\mathrm{Lat}\right).Math.\tan \left({\mathrm{Sundip}}_2\right)\right)$

where Lat represents a latitude, in units of rad; and Sundip.sub.2 represents a solar declination angle, in units of rad.

[0038] A formula of the solar declination angle is expressed as follows:

[00010]${\mathrm{Sundip}}_2=0.409.Math.\sin \left(2.Math..Math.\frac{{\mathrm{Date}}_1}{{\mathrm{Date}}_2}-1.39\right)$

where Date.sub.1 represents a day of a year, which is an ordinal number of the day in the year; and Date.sub.2 represents a total number of days of the year, which is 365 for a common year, or 366 for a leap year.

[0039] A formula of the extraterrestrial solar radiation SR.sub.extra is expressed as follows:

[00011]${\mathrm{SR}}_{\mathrm{extra}}=118.08.Math.\frac{\mathrm{Distance}}{}.Math.\left({\mathrm{Sundip}}_1.Math.\sin \left(\mathrm{Lat}\right).Math.\sin \left({\mathrm{Sundip}}_2\right)+\cos \left(\mathrm{Lat}\right).Math.\cos \left({\mathrm{Sundip}}_2\right).Math.\sin \left({\mathrm{Sundip}}_2\right)\right)$

where SR.sub.extra represents the extraterrestrial solar radiation, in units of MJ/m.sup.2; Lat represents a latitude, in units of rad; Sundip.sub.1 represents a sunset hour angle, in units of rad; Sundip.sub.2 represents a solar declination angle, in units of rad; and Distance represents a relative Sun-Earth distance, in units of astronomical units (AU).

[0040] A formula of the relative Sun-Earth distance is expressed as follows:

[00012]$\mathrm{Distance}=1+0.33.Math.\cos \left(\frac{2.Math..Math.{\mathrm{Date}}_1}{{\mathrm{Date}}_2}\right)$

where Date.sub.1 represents a day of a year, which is an ordinal number of the day in the year; and Date.sub.2 represents a total number of days of the year, which is 365 for a common year, or 366 for a leap year.