Solar panel orientation - Optimal orientation and tilt increase yield; trackers automate angle adjustments throughout the day.

Solar panel orientation is a critical factor in maximizing the efficiency and power output of a photovoltaic (PV) system. It refers to both the direction (azimuth) the panels face and the angle (tilt) at which they are installed. The goal is to position the panels to be as perpendicular to the sun's rays as possible throughout the day and year, thereby maximizing the amount of sunlight they can absorb.

Direction (Azimuth)
The optimal direction for solar panels depends on which hemisphere you are in.

Northern Hemisphere: The sun's path across the sky is in the south. Therefore, panels should ideally face true south to capture the maximum amount of sunlight throughout the day.

Southern Hemisphere: The sun's path is in the north. Panels should ideally face true north for optimal performance.

While facing due south or north is the most efficient for annual energy production, a slight deviation (e.g., facing southeast or southwest) is often acceptable and can even be beneficial in certain situations. For instance, some homeowners may choose an east-west orientation to balance power production, generating more electricity in the morning (east-facing panels) and evening (west-facing panels) to align with their household's peak energy usage times.

Angle (Tilt)
The optimal tilt angle is determined by your geographical latitude and the time of year. The general principle is to set the angle so that the panels are perpendicular to the sun's position in the sky.

Fixed Tilt: For systems with a fixed tilt, a common rule of thumb is to set the panel angle equal to the latitude of the installation location. This provides a good balance for year-round production. For example, if you live at 30° North latitude, a 30° tilt angle is a common choice for a fixed system.

Seasonal Adjustment: To optimize performance, the tilt angle can be adjusted seasonally to account for the sun's changing position.

Summer: The sun is higher in the sky, so a flatter angle is needed. A general guideline is to subtract 15° from your latitude.

Winter: The sun is lower in the sky, so a steeper, more vertical angle is needed. A general guideline is to add 15° to your latitude.

Spring/Autumn: The sun's position is in the middle, and the tilt angle can be set close to the geographical latitude.

Other Important Factors
Beyond direction and tilt, several other factors can affect the optimal orientation of solar panels:

Shading: Any shade on a solar panel, even from a single tree branch or chimney, can drastically reduce the output of the entire system. A thorough shade analysis is crucial to identify and avoid obstructions.

Roof Pitch and Orientation: On a rooftop installation, the panels are often limited by the existing roof's angle and direction. While this may not be ideal, most installations can still achieve a high level of efficiency as long as the roof is not facing true north (in the Northern Hemisphere).

Local Climate: Regions with frequent morning fog might benefit from a more west-facing orientation to maximize power generation in the afternoon when the sky is clear.

Time-of-Use (TOU) Electricity Rates: In areas with TOU billing, electricity is more expensive during peak usage hours (e.g., late afternoon and early evening). In these cases, a west or southwest-facing orientation might be more financially beneficial than a south-facing one, as it generates more power when electricity rates are at their highest.