Why do we need a shadow-free area for solar installation?
You must have read this line before: “A shadow-free area is required to install the solar panels at your location.”
Before installing the solar panel at your place, the installer might have checked for the shadow-free area at your location. Also, the Ministry of New and Renewable Energy (MNRE) reported that for a one kWp solar plant, an area of about 10 square meters shadow-free area is required.
But, as a consumer, you might wonder, “why this shadow-free area plays such an important role in solar panel installation?”
To answer this in simple terms the output of the solar plants gets deteriorated when a shadow falls on the panel.
The solar radiation incident on the solar panel is converted into useful electrical energy using the photovoltaic principle. What this means is that the output of a solar plant depends on the solar radiation intensity. So, even a slight shadow on one string can affect the entire solar plant’s output efficiency.
In this article, you will learn how shadows affect your solar power plant and some lesser-known tips to avoid shadows.
How Does Shadow Impact A Solar Power Plant?
Lower Output Energy
The primary impact of shadows on a solar power plant is the reduction in its output energy. The drop in energy output increases with the increase in the size of the shadow.
The output of the solar panels gets considerably reduced when a shadow from a nearby object falls on it. In terms of shadowing, one can look at the solar panels as pieces of pipes and the water flowing as solar output, while shading can be viewed as stone or any other obstruction to water flow, as shown in the below figure. A stone clogged in a pipe will block the flow of water, in the same way, a shadow on a panel will prevent the solar radiation from reaching the panel.
The strings in the solar panels are arranged in a series or parallel fashion. In the case of series connections, partial shading reduces output by 50%, while in parallel connections, the output is reduced by 90%. This can be prevented by carefully installing the solar panels in a shadow-free area where the nearby objects do not cast shadows on the solar panels.
If the hotspot stays for a longer duration crossing its threshold limit, the particular string may cause the solder joints in the module to melt, thus destroying the busbar and eventually the solar cell.
Approval of Net Metering Bills
Solar net metering consents consumers to produce, borrow and sell electricity to the connected utility grid.
So far, 19 Indian states have approved the net metering policy. The policy gives consumers the right to receive compensation for the extra solar power they generate and send to the grid. This way, they can offset their electricity bill or even earn revenue from their rooftop solar panels.
The cast of shadows on the solar panel will not only affect its output and lifespan but can also impede the approval of net metering.
Manufacturers recommend that modules only be installed in shadow-free areas to guarantee their warranty. Therefore, modules installed in shadows cannot be claimed by the supplier.
Best Tips to Avoid Casting of Shadows on Solar Panels
Check Your Surroundings Before Installation
Make sure to check the surroundings of your house or commercial building before installing solar panels. Look out for trees, buildings, high-voltage grids and other objects that may cast a shadow on your solar panels during certain times of the day.
You should check the shadows cast by these objects at different times of the year to get an estimate of how much they will impact your solar panels’ output.
To further future proof your installation, do your due diligence on upcoming buildings in your locality and figure out how and why they would affect your solar panels.
Go for an Elevated Design Structure
In the rooftops of houses, the solar panels are usually installed at a height of around 1.5 to 2 meters. However, you can increase this height to 4 meters or more to avoid casting shadows on your solar panels.
This will also protect your solar panels from animals, birds and other objects that may fall on them and cause damage.
Frequently Clean the Solar Panels
Frequently cleaning your solar panels is important to maintain their efficiency. However, you should also regularly check the condition of your solar panels and look out for any signs of damage. If you notice that a shadow is starting to fall on one of your solar panels, you can quickly adjust its position to avoid any decrease in output.
Ensure Sufficient Distance Between Solar Panels to Avoid Overlapping
You can also increase the distance between your solar panels to reduce the chances of one panel casting a shadow on another. This will maximize the amount of sunlight that each panel receives and help you get the most out of your solar installation.
Install Modules at an Angle
Installing your solar panels at an angle will help you avoid casting shadows on them. This is because the sun’s rays will hit the panels directly, and the shadows will be cast behind the panels.You can use special brackets to angle your them.
What If You Can't Avoid Shadows On Your Solar Panels?
In this situation one can take the below-mentioned steps to optimize the solar output:
- If one cannot remove the objects placed on the roof, one can wisely place the components as placement of components can reduce the impact of shadow on the panels at least during peak sun hours.
- One can get rid of the partial shadow impact by using a microinverter (these inverters come with a maximum power point tracker). As each microinverter has an MPPT, and as they are connected in parallel, each solar panel will operate at its optimum point even during partial shading conditions without impacting other panels.
- Another option is to use a power optimizer to improve the solar panel efficiency when one cannot prevent shadows from falling on the panel.
But it is advisable to choose a location where no neighboring objects cast a shadow on the panel to ensure the long run of the solar panel with an optimum ROI.
Our design team identifies the best location with an appropriate design structure in order to maximize the return on the installed plant. For any info contact us. Our technical team will be happy to assist you with the best possible solution.