Mono Vs. Poly Solar Panels: Which Pulls Its Weight in Low Light
- How Sunlight is Converted to Energy
- The Anatomy of a Solar Cell: Two Blueprints
- Head-to-Head Comparison of Poly and Mono
- Low-Light Challenge: The Worth of Overcast Days
- Winner in the Dark: Best Panel for Low Light
- Getting the Most Out of Every Ray: EcoFlow 400W Solar Panel
- Pro Tips for Maximum Power in All Weathers
- The Last Word
You’ve opted to tap into the power of the sun. It’s a wonderful step toward independence from the grid, lower bills, and a lowered carbon footprint. But then you begin to consider your options and you’re suddenly confronted with an initial decision: monocrystalline solar panels or polycrystalline solar panels. The specs for each are rife with numbers, so the advice can be confusing.
Also among the most practical questions to pose is what occurs when the sun is less than fabulous. What of cloudy winter afternoons, overcast morning skies, or the filtered light of a tree-shaded campsite? Under these everyday circumstances you need a solar panel that works just as well. This article will dispense with the technical doubletalk to offer an easy-to-understand breakdown of these two top technologies and reveal which one really does work when the sky is less than an ideal blue.
How Sunlight is Converted to Energy
So set competition aside for the moment and let’s discuss some of the science involved. Solar panels operate by using the photovoltaic effect. Consider sunlight as a beam of tiny energy-carrying particles called photons. When the sun’s light strikes a solar panel, it knocks loose the electrons of atoms in solar panel silicon cells. The free electrons are routed along to generate direct current (DC) electricity to charge your gadgets or store in a battery.
The secret to the performance of the panel is in the way those electrons move freely. The inner crystal structure of the silicon cell does that for us. That is basically where the monocrystalline/polycrystalline technology distinction comes from.
The Anatomy of a Solar Cell: Two Blueprints
Though both types of major panels utilize silicon, the process of turning silicon into a cell creates two very different products that appear differently and possess differing performance characteristics.
Monocrystalline Solar Panels: The Single
The term “mono” refers to one. Monocrystalline solar panels are made from one piece of extremely purified silicon crystal. They are very complicated to produce. A silicon crystal “seed” is submerged in molten silicon in a vat and pulled upward very gradually to form an enormous cylindrical ingot. This perfect, uniform crystal is very thinly sliced to make very thin wafers.
Since the crystal is a single piece, the electrons are able to move in a continuous straight path. Think of a freeway with no intersections or red lights—cars simply move along uninterrupted. This obstruction-free path is the key to higher efficiency in a monocrystalline cell.
You can commonly recognize these panels visually. The very pure silicon gives them a uniform dark black look. The wafers are sometimes trimmed with rounded edges to fit the panel and contain small diamond-shaped gaps between the cells. Their high-gloss, sleek look is the direct result of single-crystal form.
Polycrystalline Solar Panels: The Many
“Poly” is a word that means many. To produce polycrystalline solar cells, producers take silicon pieces—usually waste from the monocrystalline process—and melt them all together in a big, square container. When the molten silicon cools, it doesn’t grow into a single perfect crystal. It grows into a mosaic of many different crystals all bonded together.
Imagine this as a grid of a city with multiple intersections. Despite continued travel of the electrons in the material, routes of travel involve crossing boundaries of multiple crystals. Each boundary creates some form of hindrance, resulting in some degree of resistance to electricity’s passage through it. This structural diversity is the source of the inferior efficiency of the polycrystalline panels compared to monocrystalline ones.
They reveal themselves in their form. The different crystals refract light in different ways, creating the panes’ classic speckled, glittering blue look. Because the cells are cast in square form, there are no seams between them but instead square cells that fit neatly onto the pane with a smoother, tiled look. This simpler process is less wasteful and results in a cheaper cost.
Head-to-Head Comparison of Poly and Mono
Now that we understand where they originate from, let’s set them side-by-side and examine them based on those criteria that are most relevant to the consumer:
- Efficiency: Monocrystalline panels are the clear winner in this regard. Due to the single-crystal configuration of monocrystalline panels, you can generate greater electricity from the same space of sunlight. Monocrystalline panels’ average efficiency is 18% to more than 22%. Polycrystalline panels average 15% to 17%. That is to say that when you need to utilize limited roof space or installation space, then you can generate power from the limited space using a monocrystalline panel.
- Price: Polycrystalline panels are less expensive. The manufacturing process is simpler, less time-consuming, and less wasteful of material, making the end cost less expensive. When there is a large project where there is enough space and reducing the initial cost is the biggest priority, then polycrystalline might be a cheap alternative. Monocrystalline panels are more expensive because the production cost is more expensive with increased complexity and more energy consumption.
- Heat Resistance: The higher heat reduces the efficiency of solar panels slightly. Monocrystalline panels are better in terms of heat resistance. Monocrystalline panels possess a lower temperature coefficient, meaning that the power delivery drops less in extreme heat. If you live in the hot sun-intensive sun belt climate, a monocrystalline panel will retain its efficiency lead better in the peak heat of the days.
- Lifespan: The two technologies are extremely durable and built to last. A 25-year plus performance warranty is common with the majority of monocrystalline and polycrystalline panel manufacturers. You can look forward to decades of constant power generation with either of the sources.
Low-Light Challenge: The Worth of Overcast Days
The output of the solar panel is directly proportional to the number of photons striking it. If it’s a clear sunny day with plenty of sunlight, numerous photons are striking the panel, and it delivers high current.
In low light—the kind that’s available on an overcast day, dawn or sunset—the available photons decrease immensely. That means fewer electrons become dislodged and the electricity current is weaker with less total power delivery. This holds for all solar panels. The concern is, what kind of panel does better with this drop-off?
Winner in the Dark: Best Panel for Low Light
In dim light, monocrystalline solar panels perform better compared to their counterpart polycrystalline panels.
This is because of the manner in which monocrystalline cells are produced. The higher purity along with the single-crystal lattice of the monocrystalline cell is an extremely efficient absorber of all incident light photons. Low sunlight high efficiency is particularly useful. The monocrystalline panel extracts as much as it can from weak light input, maintaining high useful levels of power production.
Polycrystalline panels contain internal crystal boundaries that are of disadvantage as the flow of photons is lessened. The resistance within the cells becomes an increasingly dominant limitation factor, and their efficiency and power decrease with a steeper curve compared to that of a monocrystalline panel.
A third type of less common variety is the thin-film panel, which works extremely well under low light too. It’s considerably less efficient overall (approximately 10-12%), though, so it’s used chiefly for specialized, flexible applications rather than for main home power or RV power production.
For those in need of power during all four seasons of the year as well as within weather changes, the research is quite clear: monocrystalline technology is the solution for low light performance.
Getting the Most Out of Every Ray: EcoFlow 400W Solar Panel
First is the knowledge that monocrystalline technology provides the most performance in actual operating situations. Second is the selection of a panel that embodies this technological advantage. The EcoFlow 400W Rigid Solar Panel is one such example of this technology utilized for optimal power and performance.
As a high-efficiency monocrystalline solar panel, it’s optimized to perform in the entire range of situations, from ideal sun to cloudy skies. Its industry-best 23% conversion efficiency draws an amazing quantity of power from every sunbeam it absorbs. That high efficiency lets you deploy an impressive solar array in space-constrained applications. One panel generates an astonishing 400 watts of power, and it’s easy to string multiple panels end to end to power everything from a portable power station to an entire off-grid cabin.
The panel is easy to mount on any vehicle’s roof, van roof, or ground rack. Its weatherproof design with an anti-corrosion aluminum frame and extended IP68 waterproofing is designed to withstand years of weathering to endure. You’re not just buying hardware when you buy the EcoFlow 400W panel; you’re investing in a reliable source of clean power in the form of high-performance monocrystalline technology.
Pro Tips for Maximum Power in All Weathers
The most important decision for use in low light is the use of a high-performance monocrystalline panel, but you’ll be able to further enhance your system with some easy methods:
- Direction and Tilt Angle: Your panels will always need to be directly in front of the sun. In fixed systems, this will be south in the northern hemisphere. Tilt angle adjustment to be higher in winter will enable sunlight to be harvested when the sun is on the horizon.
- Keep Them Clean: A thick layer of dirt, dust, or heavy snow will be an insulator between sunlight and panels. Clean your panels with water and some soft cloth regularly so that no blockage is present on the surface to receive full light.
- Avoid Shadows: A shadow that lands on some portion of your panel can reduce its overall efficiency by quite a bit. Consider trees, roof vents, and other obstructions while selecting an installation location that is permanent.
The Last Word
The selection between monocrystalline solar panels and polycrystalline solar panels is the classic performance vs cost dilemma. Polycrystalline solar panels offer an economically viable option for people with an ample supply of space and high sun exposure.
But for those customers that need higher efficiency, higher heat performance, and most importantly, higher dependability of power production on cloudy days, monocrystalline solar panels will be the clear victor. Their single-crystal design provides them with an unmistakable advantage that is particularly noticeable when sunlight is in short supply. Investing in high quality monocrystalline technology is investing in solar that is actually engineered specifically for the genuine world with its weather included.