Solar Panel Mounting Structures SS1 Solar Photovoltaic Installation & Maintenance Lesson Note

Types of Mounting Structures

Where do we put the panels? Depending on the house or the land available, we use different “skeletons” to hold them.

1. Roof Mounts: The most common in Nigeria. We use aluminum rails to bolt the panels directly onto the roof.
   1. Tip: We must ensure the roof is strong enough to carry the weight.
2. Ground Mounts: Used when the roof is too small or facing the wrong way. We build a metal stand on the ground, usually made of galvanized steel or aluminum.
3. Pole Mounts: You see these on solar streetlights. The panel sits on top of a single pole.
4. Carport Mounts: A “two-in-one” solution where the solar panels act as the roof of a parking lot, providing shade for cars while making electricity.

Orientation (Which way should they face?)

In the “Solar World,” the direction your panel faces is everything.

• The Rule for Nigeria: Because Nigeria is in the Northern Hemisphere (above the equator), the sun is always slightly to our South.
• The Direction: Therefore, we always try to face our panels toward the True South.

What happens if you face them North? You will lose a lot of power because the sun will be “behind” the panel for most of the day. If you cannot face South because of the shape of the roof, East (to catch morning sun) or West (to catch afternoon sun) is the next best choice.

The Tilt Angle (The “Slant”)

Should the panels lie flat or stand up? This is what we call the Tilt Angle.

If a panel is flat (0°), dust and bird droppings will gather on it and block the sun. If it is too steep, the sun might miss it.

• The Magic Number for Nigeria: We usually tilt panels between 15° and 20°.
• Self-Cleaning: This angle is “steep” enough so that when it rains, the water washes the dust away naturally.
• The Location Factor: If you are in Lagos (further South), your angle might be smaller (around 15°). If you are in Maiduguri (further North), you might tilt it a bit more (around 25°).

Site Assessment (Checking the Area)

Before an installer even touches a screwdriver, they must do a Site Assessment. This is like a doctor examining a patient before giving medicine.

1. The “Shadow” Test: We look for trees, tall buildings, or even NEPA poles that might cast a shadow. Remember: A shadow the size of a hand can “choke” the power of a whole panel.
2. Roof Health: If the wood (purlins) under the roof is rotten, the panels might fall through. We check if the roof needs repairs first.
3. Distance to Battery Room: If the panels are on the roof and the batteries are in the backyard, you need long wires. Long wires cause “Voltage Drop” (power gets lost along the way). We try to keep the distance as short as possible.

Summary and Class Activity

Key Points to Remember

• Direction: Always face South in Nigeria.
• Tilt: Keep it around 15°−20° to catch the most sun and let rain wash off dust.
• Mounting: Ensure the structure is non-corrosive (won’t rust) like Aluminum or Galvanized Steel.

Class Activity: The “Sun-Hunter”

1. Go outside to the school compound. Use a compass (or look at where the sun rises and sets) to find South.
2. Identify a building on the compound. Which side of the roof is the best for solar? Is there a tree blocking it?

Discussion: Why is it a bad idea to use “ordinary iron” (black iron) to build a solar stand in a place like Lagos or Port Harcourt? (Hint: Think about the salty air and rain).