The best solar panels are determined by a few things. When you’re looking for the best solar panels for your system, keep the following points in mind.
Budget is the most important aspect in most people’s design selections.
There are a variety of sizes available for panels. Full-sized panels usually vary from 375 to 655 watts, but smaller panels for off-grid applications are also available.
Price-per-watt is a tremendous equalizer. Subtract the cost of the panel from the number of watts it generates. You’ll be given a “real” pricing number that you may use to compare all panels on an equal footing.
Performance and workmanship warranties are the two types of warranties available.
For the length of the warranty, the performance warranty ensures that your panels will perform at or above their rated efficiency. After 25 years, most manufacturers guarantee that solar panels will perform at or above 80% efficiency.
The industry standard is 25 years; however, a few manufacturers provide 30-year performance warranties.
Then there’s the guarantee on workmanship. This safeguards your panels from manufacturing flaws and other physical issues.
The workmanship warranty lasts for a shorter period than the performance warranty. A generous workmanship warranty is a good sign that the manufacturer is confident in the quality of their goods.
The standard industry workmanship warranty is ten years; however, some manufacturers provide guarantees of up to twenty years.
The amount of sunlight that a solar panel can convert into useful energy is determined by its efficiency rating. For panels produced by leading manufacturers, a range of 14-22 percent efficiency is acceptable.
The output of a solar panel is directly related to this (in watts). For example, a 415W panel from Canadian Solar is 20.4 percent efficient, whereas a 545W module from the same manufacturer is 21.3 percent efficient.
Coefficient of temperature
In ideal conditions, the best solar panels are tested. Manufacturers conduct experiments in a climate-controlled facility to determine panel output.
The actual world, of course, will bring with it less-than-ideal circumstances. Your system will perform below its rated efficiency during the scorching days of the Nigerian heat.
Temperature coefficient describes how temperature affects real panel output. For each degree above or below optimum test conditions, the coefficient calculates how much efficiency is lost.
Because most manufacturers quantify energy loss per 1°C temperature change in Celsius, we’ll use that as an example.
Let’s say a panel was tested at 45 degrees Celsius but is now at 55 degrees Celsius. You can double the temperature coefficient by the difference in temperature (10° C) if it’s 0.4 percent Wp (Watt power). On that day, the panel’s efficiency is 4% below its rated value.
For voltage, amperage, and wattage, there are independent temperature coefficients. At higher temperatures, some types of solar panels, such as monocrystalline, perform slightly better.
Unless you live in a region that gets exceptionally hot, the temperature coefficient is usually not the most crucial variable to pay attention to. This is because heat affects the efficiency of your solar panels, resulting in lower output.
History of the Company
Our recommendations are influenced by the panel manufacturer’s history and reputation. What good is a warranty if the manufacturer fails to honor it before they have an opportunity to do so?
As a result, we look for companies who have a long history in the solar industry. Every item on this list is made by a well-known company that is unlikely to go out of business very soon.
Underwriters Laboratories has been in existence for more than a century. To guarantee that items are safe for public use, UL develops standards and conducts safety tests.
If you’re installing solar panels on your house, they must meet UL 1703 criteria.