“How much will my solar plant generate?” - This question may have crossed your mind at least once if you have ever thought of using solar for your energy requirements.
When you are looking to go solar, the four major factors that you should consider, during and after the installation of rooftop PV solar systems are:
1. Shade:
Looking at a shaded solar PV installation, you must have thought to yourselves, "Is that a proper/ correct installation?"
Shading of solar panels is sometimes unavoidable, due to many reasons, including a tree near the solar array that you are unwilling to trim, or perhaps there is a fixed object nearby like a utility pole or adjacent building. But a lot of times it could be incorrect installation or improper site assessments, which are avoidable.
Shaded solar panels won’t produce the same amount of energy as those in direct sunlight, due to mismatch loses. Also you may have to shell out extra in the form of electric bills (in case you have a net-metered system).
If your roof is sun-deprived by un-trimmable trees or building, a proper site assessment before you opt-in for solar can help save a lot of money from going down the drain.
Tip: Ask your contractor if there are any shading issues over potential panel sites on the roof or if they have done a shadow analysis of your site.
2. Seasonality:
Like the weather, solar power production varies day-by-day and month-to-month. A cloudy, winter day won’t be as productive as a sunny, summer one. But it’s important to focus on the year-round picture. While assessing your solar requirement, it is important to consider annual and monthly load variations along with the seasonal shift in power production. You won’t want to have a system based on your energy consumption during winters to pay up electric bills for increased AC consumption during summers. It has to be the right system size to ensure maximum savings.
3. Tilt:
Unlike a pinball machine, solar panels can benefit from a good tilting. The direction your home/office is facing, its location, and even your roof’s pitch, have a significant effect on how well a rooftop PV solar system works. Ideally, solar panels should be at the same angle as the latitude where they’re mounted. Pitches between 15 degrees to 25 degrees usually work well in most scenarios throughout the sub-continent.
4. Azimuth:
The solar azimuth angle is the compass direction from where the sunlight is coming. At noon, the sun’s light comes from the south in the Northern Hemisphere and from the north in the Southern Hemisphere. The wrong azimuth angle could reduce the energy output of a solar home panel by up to 35%.
An azimuth of zero (southwards - facing the equator) is usually the best choice. The north facing roof is not suitable for installing solar panels in India, whereas the east and west facing roofs could be acceptable. Usually, west facing roofs are more advantageous than east facing roofs, since the solar radiation is more powerful in the afternoon.
Do you have queries about how solar works or would you like some help in planning your solar install? Our Solar advisors are here to help you.
