Installing solar panels is an excellent method to save electricity and minimize electricity expenses. However, understanding the distinctions in solar panel manufacturing is critical in order to select the most efficient solar panels for your business or home installation.
If you’ve done your research on the best solar panels available and have opted to emphasize efficiency, you’ve made a wise decision. Purchasing the highest efficiency solar panels gives you the most value for the money when working with limited roof space and is frequently (but not always) the best choice for homeowners.
Solar panel efficiency, in its most basic form, refers to the quantity of sunlight that falls on the panels and is turned into energy, or solar power. In this post, we’ll explain why solar efficiency is crucial and how to choose the most efficient solar panels for your home.
The quantity of sunlight (irradiation) that falls on the surface of a solar panel and is turned into energy is measured by solar panel efficiency. Because of recent developments in solar technology, the average panel conversion efficiency has risen from 15% to well over 20%. Because of this significant increase in efficiency, the power rating of a standard-size panel increased from 250W to 370W. The most efficient solar panels on the market today only achieve around 22.8 percent efficiency (holler to Sun Power), which means that the panel converts roughly 22.8 percent of the sun’s irradiance into useable AC energy.
As detailed further below, solar panel efficiency is influenced by two major elements: photovoltaic (PV) cell efficiency, which is driven by cell design and silicon type, and overall panel efficiency, which is determined by cell layout, configuration, and panel size.
The cell structure and substrate utilized, which is often P-type or N-type silicon, affect cell efficiency. The fill factor (FF), which is the highest conversion efficiency of a PV cell at the optimal operating voltage and current, is used to determine cell efficiency.
Panel efficiency is greatly influenced by cell design. The silicon type, busbar arrangement, and passivation type are all important characteristics to consider (PERC). Due to the high purity N-type silicon substrate and negligible busbar shading losses, panels constructed using high-cost IBC cells are now the most efficient (20-22 percent). Panels built using the most recent monocrystalline PERC cells and more sophisticated heterojunction (HJT) cells, on the other hand, have attained efficiency levels far beyond 20%.
Solar panel efficiency is determined under standard test settings (STC), which are 25°C cell temperature, 1000W/m2 solar irradiation, and 1.5 Air Mass. A panel’s efficiency (percentage) is efficiently computed by dividing the maximum power rating, or Pmax (W) at STC, by the whole panel area measured in meters squared.
Many factors can affect overall panel efficiency, including temperature, irradiance level, cell type, and cell connectivity. Surprisingly, the color of the protective back sheet might have an impact on efficiency. A black back sheet may appear more visually beautiful, but it absorbs more heat, raising cell temperature and increasing resistance, which affects overall conversion efficiency marginally.
Solar panels constructed with advanced ‘Interdigitated back contact’ or IBC cells are the most efficient, followed by heterojunction (HJT) cells, half-cut and multi-busbar monocrystalline PERC cells, shingled cells, and lastly 60-cell (4-5 busbar) mono cells. 60 cell polycrystalline or multi-crystalline panels are often the least efficient and also the least expensive panels.
Let’s take a look at the most efficient solar panels accessible in 2022, given all of the recent improvements in solar technology. These are the most efficient solar panels at the time of writing, according to our research:
|Most Efficient Solar Panels||Efficiency Rating||Power|
|Jinko Solar||22.3%||620 W|
|REC Solar||21.9%||405 W|
|Trina Solar||21.6%||670 W|
|LONGi Solar||20.6%-21.4%||485-505 W|
|Q Cells||20.6%||360 W|
The wattage output or maximum power capability of the panel is referred to as power. The more powerful a solar panel is, the more electricity it can generate. It’s worth noting that power influences, rather than determines, % efficiency.
Although the term “efficiency” is frequently used, it is important to remember that a little more efficient panel does not automatically imply a higher-quality panel. When choosing a solar panel, many people believe efficiency to be the most essential factor, but what counts most is manufacturing quality, which is linked to real-world performance, dependability, manufacturer service, and warranty terms.
In terms of the environment, improved efficiency implies a solar panel will pay back its embodied energy (energy needed to extract raw materials and produce the solar panel) in a shorter amount of time. According to a rigorous lifetime study, most silicon-based solar panels pay for themselves within two years, depending on location. Payback period has been decreased to less than 1.5 years in many regions as panel efficiency has improved by over 20%. Increased efficiency also implies that a solar system will generate more power during the normal 20+ year life of a solar panel and will pay for itself sooner, boosting the return on investment (ROI).
The efficiency of a solar panel is a strong indicator of its performance, especially since many high-efficiency panels employ higher-grade N-type silicon cells with a better temperature coefficient and less power deterioration over time. Some manufacturers, such as LG, Panasonic, and SunPower, even provide 25-year guarantees that guarantee 90 percent or higher power output retention.
Efficiency makes a significant impact on the amount of roof area required. Higher efficiency panels produce more energy per square meter and so require less total space. This is ideal for rooftops with limited space, but it can also allow bigger capacity systems to be installed on any roof. For example, 12 × high efficiency 400W solar panels with a 21.8 percent conversion efficiency, such as those from LG or SunPower, will produce roughly 1200W (1.2kW) more total solar capacity than the same number of comparable size 300W panels with a lower 17.5 percent efficiency.
At the risk of seeming too technical, here are a few key features of solar panels that affect efficiency.
A solar cell’s ability to absorb a certain wavelength of light varies. Most contemporary solar cell technology can only capture visible light and cannot capture additional wavelengths such as infrared and UV radiation. In general, the more light that can be caught, the more efficient the cell. Some researchers are now working on solar cells that can capture infrared wavelengths, which would greatly boost efficiency.
Extreme weather conditions and high temperatures may put a lot of strain on a solar panel. In reality, solar panels are more effective in cooler weather since they do not overheat. Panels that are tough and can endure high temperatures will have a longer lifespan and be more efficient.
To maintain their lifespan, solar panels require a protective coating. The difficulty is that this protective coating should not reflect any of the potential energy that the solar cells are attempting to gather. Higher-efficiency panels will have high-quality protective coatings that reflect as little light as possible, resulting in increased overall energy production.
As the industry recognizes the potential of solar panels, solar panel producers continue to achieve significant advances in efficiency. Residential solar systems, which often have the least amount of area to work with, benefit from highly efficient mono-crystalline panels. As a result, the majority of leading solar firms should be qualified to sell and install the most efficient solar panels indicated above.
If you want to invest in high-efficiency panels, we recommend contacting solar panel installation companies in your area to learn more about their product offerings. You’ll be well equipped to choose the proposal with the most value for your money now that you know so much about solar efficiency and why it matters.
Fill out the form on our website to get started connecting with qualified local installers.