🔥🔥 Don’t Miss Out on Our End of Autumn Sale. If you have any questions, feel free to click the bottom right corner to contact our customer service..

Concat us[email protected]
Shopping Cart

No products in the cart.

🔍
BSI PD IEC TR 63149:2018

BSI PD IEC TR 63149:2018

$215.11

Land usage of photovoltaic (PV) farms. Mathematical models and calculation examples

Published By Publication Date Number of Pages
BSI 2018 76
PDF Format Searchable Printable Preview Now
Guaranteed Safe Checkout
Category:

If you have any questions, feel free to reach out to our online customer service team by clicking on the bottom right corner. We’re here to assist you 24/7.
Email:[email protected]

This document is aimed at building mathematical models for calculation of the distance between arrays, to farthest avoid shading and reasonably reduce the land usage of PV farms.

In general, there will be longest south-north shading on the day of the winter solstice. The boundary condition to calculate the south-north (S-N) distance between PV arrays used in this document is based on winter solstice. The longest east-west (E-W) shading is on the time when the sun is in the east. The users can change the boundary conditions (date and time) depending on local conditions (latitude, land limitation, facing direction, etc.), the formulas are all the same.

The shading distance calculation is based on date and time boundaries, not based on shading energy losses that may be very complicated. The no-shading distance calculation in this document is only for the distance between PV arrays, not for other surrounding objects, but the formula can also be used to calculate the no-shading distance between the objects and PV arrays. Where shading occurs on the PV array site other calculations are required that are not within the scope of this document. The no-shading distance calculation is based on the northern hemisphere in this document, but all fomulas can also be used for the southern hemisphere.

The no-shading calculation model is different for fixed PV arrays and PV systems with solar trackers. This document derives mathematical models for both fixed PV arrays and solar trackers.

For solar trackers, there are 2 different coordination systems: the Ground Horizontal Coordinates (GHC) and Equatorial Coordinates (EC).

This document provides land usage calculations of PV farms for the following array types:

  • Fixed PV array on flat-land and face to the south

  • Fixed PV array on flat-land and face to non-south direction

  • Fixed PV array on tilted land and face to the south

  • Horizontal E-W tracking in Equatorial Coordinates

  • Tilted E-W tracking in Equatorial Coordinates

  • Pole-Axis tracking in Equatorial Coordinates

  • Double tracking in Equatorial Coordinates

  • Solar Azimuth tracking in ground horizontal coordinates

  • Manual solar altitude tracking in ground horizontal coordinates

  • Double tracking in ground horizontal coordinates

In the following clauses, the different coordinates systems are introduced and the land usage calculations for different operational models are provided.

PDF Catalog

PDF Pages PDF Title
2 undefined
4 CONTENTS
7 FOREWORD
9 INTRODUCTION
10 1 Scope
11 2 Normative references
3 Terms and definitions
13 4 Azimuth and hour angle coordinates
14 Figures
Figure 1 – Current definition of azimuth and hour angle coordinates
Figure 2 – Definition of azimuth and hour angle coordinates for this document
15 5 Coordinate systems (Figures 3 to 6)
5.1 Ground Horizontal Coordinates (GHC)
Figure 3 – PV array in ground horizontal coordinates
16 5.2 Equatorial Coordinates (EC)
Figure 4 – PV array in equatorial coordinates
Figure 5 – Equatorial tracking systems
17 6 Boundary conditions
Figure 6 – Relationship between A, Ω and ω
18 Tables
Table 1 – No-shading set time on winter solstice for various latitudes
Table 2 – Date and time when solar altitude is 20° and the sun is in the east
19 Table 3 – Proposed boundary conditions
20 7 Land use calculations for fixed PV arrays on flat land (Figure 7)
7.1 Boundary conditions
7.2 Calculation models for the fixed PV arrays on flat land
Figure 7 – Fixed PV array on flat land
Figure 8 – Relationship of solar beam and PV array
21 7.3 Example of land usage for fixed PV arrays on flat land
22 8 Special consideration of non-south direction and sloped land
8.1 General
8.2 Boundary conditions
23 8.3 Calculation models
Figure 9 – Relationship of solar beam and PV array and the distance between arrays
24 8.4 Example for fixed PV arrays with non-south direction
25 8.5 Example for fixed PV arrays on sloped land
26 9 Land usage for solar altitude tracking in ground horizontal coordinates (Figures 10 and 11)
Figure 10 – Manual adjusted supporting structure
27 9.1 Boundary conditions
Figure 11 – Manual adjusted PV array
28 Figure 12 – 2 times adjustment rules
Table 4 – Adjustment rules for solar altitude tracking
29 9.2 Calculation models for solar altitude tracking
9.3 Example of land usage for 4-times adjustment
Figure 13 – 4 times adjustment rules
31 10 Land usage calculation for horizontal E-W tracking in equatorial coordinates (Figure 14)
10.1 Boundary conditions
10.2 Calculation models
Figure 14 – Horizontal E-W tracking
32 10.3 Example – Land usage for horizontal E-W tracking
Figure 15 – Horizontal E-W tracking
33 11 Land usage for pole-axis tracking (Figure 16)
Figure 16 – Pole-axis tracking
34 11.1 Boundary conditions
11.2 The calculation for E-W distance
35 11.3 The calculation for S-N distance
11.4 Example 1: no-shading distance is set within 75 % day length on winter solstice
36 11.5 Example 2: no-shading period is from 9:00am to 3:00pm on winter solstice
37 11.6 Example 3: Calculation for high-efficiency PV modules
38 11.7 Land usage for pole-axis tracking
40 12 Land usage calculation for double-axis tracking in equatorial coordinates (Figure 17)
12.1 Boundary conditions
12.2 Calculation model for E-W distance
Figure 17 – Double tracking systems (hour-angle and solar declination)
41 12.3 Caculation for S-N distance
42 Figure 18 – PV array and solar beam for double-axis tracking
43 12.4 Example 1: no-shading distance is set within 75 % day length on winter solstice
12.5 Example 2: no-shading period is from 9:00am to 3:00pm on winter solstice
44 12.6 Land usage for equatorial double-axis tracking
45 13 Land usage calculation for tilted E-W tracking
13.1 Boundary conditions
13.2 Why optimized S-N tilt is equal to 1/2 latitude
Figure 19 – Tilted E-W tracking (horizontal main axis)
46 13.3 The calculation model for E-W distance
13.4 Example of E-W distance calculation
Figure 20 – E-W distance for tilted E-W tracking
Table 5 – Annual average incidence angle for different latitudes and different tilts
47 13.5 The calculation model for S-N distance
48 Figure 21 – The relationship between PV array and solar beam
Figure 22 – S-N distance between PV modules
49 13.6 Example of S-N distance calculation
13.7 Land usage of tilted E-W tracking
50 14 Land usage calculation of double-axis tracking in ground horizontal coordinates (Figure 23)
14.1 Boundary conditions
14.2 Calculation model for S-N distance
Figure 23 – Double axis-tracking in ground gorizontal coordinates
51 Figure 24 – Distance items relevent with no-shading distance calculation
52 14.3 Example 1: calculation for S-N distance at 75 % day-length on winter solstice (Table 6)
53 14.4 Example 2: calculation for S-N distance at 9:00am on winter solstice (Table 7)
Table 6 – S-N distances calculation at 75 % day length on winter solstice
54 14.5 Example of E-W distance calculation
Table 7 – S-N distances calculation at 9:00am on winter solstice
55 14.6 Land usage for horizontal double-axis tracking
56 15 Land usage calculation for azimuth tracking in ground horizontal coordinates (Figure 25)
15.1 Boundary conditions
15.2 Calculation model for S-N distance
Figure 25 – Solar azimuth tracking (fixed PV tilt)
57 15.3 Example 1: calculation for S-N distance at 75 % day-length on winter solstice (Table 8)
58 15.4 Example 2: calculation for S-N distance at 9:00am on winter solstice (Table 9)
Table 8 – S-N distances calculation for azimuth tracking at 75 % day length
59 15.5 Example of E-W distance calculation
Table 9 – Distances calculation from the set time to noon time
60 15.6 Land usage for horizontal azimuth tracking
61 16 Array length and width ratio
Figure 26 – Array configuration for horizontal double tracking
62 Table 10 – Length and width ratio effect for 3 scenarios
63 Table 11 – Summary of 3 scenarios
64 17 Summary of calculation results (Table 12)
Table 12 – Summary of the calculated results
65 18 Back tracking technology
18.1 General
66 18.2 E-W tracking in equatorial coordinates
Figure 27 – Back tracking for E-W tracking
67 Figure 28 – No-shading between PV arrays by back tracking technology
69 Table 13 – Back tracking tilt calculation for E-W tracking on winter solstice
70 18.3 Double axis tracking in ground horizontal coordinates
Table 14 – Back tracking tilt calculation for E-W tracking on spring equinox
71 Figure 29 – Back tracking for horizontal double-axis tracking
73 Table 15 – Back tracking tilt calculation for D-tracking on winter solstice
74 Table 16 – Back tracking tilt calculation for D-tracking on spring equinox
75 Annex A (informative)Acronyms and abbreviated terms
BSI PD IEC TR 63149:2018
$215.11