Step 2.1 Sunpath - Polar Coordinates - GAISMA

Concept

Sunpath can be used to determine coordinate of sun (Altitude and Azimuth).

Gaisma ( https://www.gaisma.com/en/ ) is one of the online tools to determine solar path.

• The diagram below is suitable for Northern & Southern Hemisphere

Step 2.2.2 Determine Azimuth

1. Use opposite hemisphere as reference

   • If site at South Hemisphere, use North in diagram as reference.

2. From reference --> direction

   • East, azimuth is negative

   • West, azimuth is positive

3. Solar azimuth approximates [Angle from reference to line] ([Direction] of [Reference])

Kuala Lumpur at northern hemisphere, so use South as reference.

Solar azimuth approximates -125° (East of South)

Step 2.1.4 Determine sunrise and sunset time

Assumption state refers to Dec Solstice, so sunrise time is 0713, sunset time is 1910 (Local time).