Though most of today’s solar panels are nearly equivalent in efficiency, it’s important to understand what you’re paying for, and why you might want to go with a higher wattage panel in some instances, versus a lower wattage panel which is likely a cheaper system, in others. For a simple example, using the same type of materials, a 290-Watt panel will be less efficient than a 390-Watt panel. The higher the wattage, ignoring all other factors, the higher the efficiency. Seems easy, right? The truth is that the quality may vary depending on the type of materials used, and the way in which each solar cell is built, however again, we’re talking in almost negligible differences in productivity. Let’s take a look at why:
According to CleanEnergyReviews, “solar panel efficiency is determined by two main factors; the photovoltaic (PV) cell efficiency, based on the cell design and silicon type, and the total panel efficiency, based on the cell layout, configuration and panel size” (https://www.cleanenergyreviews.info/blog/most-efficient-solar-panels). This article may seem somewhat cumbersome, however it outlines the key differences pretty well – check it out! The author goes on to explain that “The efficiency (%) of a panel is calculated by the maximum power rating (W) at STC, divided by the total panel area in meters,” however if you’re not designing a system yourself, this equation isn’t the most important part – it’s understanding how this will impact your system and your budget, based on your current and perceived energy usage. Again, to understand why – let’s keep digging! If you keep reading on to find the image below, you might start to see the differences in panels the article is referencing – for example, take a look at the labels below each to note the difference between the silicon types: “multiple busbars (MBB), and passivation type (PERC)” – while we’re here, also note the percentages at the bottom of each label – the variance is only ~7% from the lowest efficiency panel, to the highest efficiency panel, however the cost difference can be significant. Keep in mind, this is not to say that the lower efficiency panel is poor quality necessarily, since you might not need the amount of energy that the higher-efficiency panels produce (these are often used for commercial projects, instead of residential homes).
Finally, this article goes on to list the top efficiency panels from 2021 (see below, updated as recently as February of this year), but the paragraph just below it really outlines the whole picture, saying “what matters most is the manufacturing quality which is related to real world performance, reliability, manufacturers service, and warranty conditions.” Please do continue reading through the end – not only is it an interesting read, but it just might help you make a more informed decision when selecting the solar panels for your solar system. For questions on the information outlined within this article, give us a call today! We’re happy to walk you through it or provide you with a free quote for your home or business.
* List of the most efficient solar panels announced and expected to reach high volume production during 2021 – Residential 60 to 66 cell size format size panels only – Last update Feb 2021.