Part 3 of 4: How do Solar Panels Work? And Poly, Mono, ARC, AI, PV … What are those?

In this 4-part series of articles Greg Shaw, Managing Director, Solar Shop Hua Hin, explains by KISS (Keep it Simple): The difference between DC and AC power; The difference between 1 and 3-Phase; How do Solar PV Panels Work?; and What is a solar inverter? Stay tuned as there will be more articles to come to help you (and our customers at Solar Shop Hua Hin) understand solar systems. If you take the time to read this 4-part series you will be rewarded with a real-life practical conclusion which you will more fully understand. And that will brighten you day because knowledge is power!

PART 3: What are the Differences between Poly and Mono Crystalline Panels and How do Solar PV Panels Work?

written by: Greg Shaw, Managing Director, Hua Hin Solar Co., Ltd.

Crystalline silicon solar panels are in wide use globally. By far the most popular panels in use today are made up of monocrystalline and polycrystalline silicon solar cells.

But wait! What are mono- and poly-crystalline solar PV panels anyway?

Monocrystalline panels are also known as single-crystalline silicon panels. They can be recognized easily by their uniform and clear black coloration which reflects the high quality silicon from which they are made. Monocrystalline solar panels have higher efficiency rates which can typically be between 15% and 20%. Because of their high power output they are space-efficient (i.e. less panels for a given power capacity) compared to any other types of panels. Since they are made of the highest-grade silicon, monocrystalline solar panels have long life-spans and may have manufacturer warranties of up to 25 years, or even 30 years. Owing to the solar cell’s high efficiencies monocrystalline panels produce up to four times the electricity current compared to thin-film solar panels. When compared to polycrystalline cells, monocyrstalline solar panels perform better in low-light conditions experienced early in the morning and late in the afternoon and in bad weather. They also perform better when the panels are shaded by, for example, a tree or adjacent building. Of course, with this good exceptional performance, these panels also come at a higher price.

Polycrystalline solar panels are based on polycrystalline silicon that was introduced in the market way back in 1981. The silicon used is raw silicon which is melted and then poured into a square molding and then cooled and cut into square wafers. The

The process of creating polycrystalline panel is lower in cost and wastage compared to monocrystalline panels. The efficiency of polycrystalline panels are also comparatively lower, between 13% and16%, owing to the fact the silicon purity used to manufacture them is not as high. It follows that due to the lower efficiency of these panels, you would need a larger space or surface for a given power output rating when installing polycrystalline panels.

From a purely aesthetic point of view, monocrystalline panels are more pleasing to look at due to their uniform and darker coloration which blend seamlessly with most roof types. This compared to polycyrstalline panels which is in speckled blue color.

But Wait a Minute! Times are certainly changing! New manufacturing processes allow for polycrystalline panels to be produced in different colors including black for aesthetic purposes. It should be noted that because polycrystalline panels are less pricey compared to monocrystalline panels they are by far the most utilized solar panel type on Earth. It should also be noted that the solar panel supply manufacturers in partnership with Hua Hin Solar also offer silver, black or even white frames. It’s also worth noting at this point that, by design, most light is absorbed by solar panels. High-quality solar panels also include Anti-Reflective Coating (ARC) to ensure that nearly all useful incoming light is absorbed. This further increases the panel efficiencies while improving their visual appearance – by reducing annoying light reflections.

And hold your horses! How do solar panels work and what is PV anyway?

PV stands for Photovoltaics and covers the conversion of light into electricity by semiconducting materials in solar panel cells using the photoelectric effect. This effect was discovered back in year 1839 by a physicist from France, Edmumd Bequerel. He discovered that an electric current will be produced when certain materials are exposed to the light. The first actual application of the PV solar panel was on a space craft dated in the 1960s. And because of the advancement of technology over the years, the technology of creating solar panels has widely improved and manufactures have created panels which are smaller, more space-efficient and increasingly affordable. Today, solar panels are commonly purchased and installed for domestic and commercial uses. They are mounted in rooftops (and on the ground) and power everything from road signs to spacecraft.

Some facts about your solar panels: Your roof-mounted solar panels are made of smaller units which are called photovoltaic cells. A 250W panel may be made up of 60 solar cells whereas a 300W panel may have 72 such cells. You will see thin strips of copper or aluminum called “busbars” between cells. These metallic strips conduct electricity from the cells to the electrical power cables of your solar system. Repeating what I wrote in PART 1: “The current flow (= electricity or power) is carried through wires from your house roof to either a Solar Charge Controller (a device used to charge up your deep cycle Solar Battery bank or your mobile phone) or a Solar Inverter (a device used to convert DC power into AC power).”

You may have seen the words “solar PV panels” on numerous occasions. What is PV anyway? The word photovoltaic is comprised of the words Photo -which means light – and Voltaic – which means producing direct electrical current from 1) chemical reactions such as those which occur in a battery or 2) the energy-producing photoelectric effect which occurs in solar panels when exposed to sunlight. So really PV simply means converting sunlight into energy.

Putting it another way …. The real processes involved in the photoelectric effect is this: When particles of light or photons knock free electrons from atoms in a semiconducting material, a flow of electricity or current is generated. This current is DC (direct current) and, in general, will need to be converted by your Solar Inverter into AC electricity to power most of the appliances and devices in your home. Repeating what I wrote in PART 1: “It is worth noting that most of the appliances/devices in your household – toasters, refrigerators, fans, lights, air conditioners, pool pumps, TVs, computers, DVD players, and so on – are AC powered.”

Hua Hin Solar Co., Ltd., is Hua Hin’s largest and most dependable solar energy company. We provide exceptional products and services at affordable prices and we offer long-term customer care. Our Team is committed to using green solar and wind energy to help our retail customers and residential/business partners make the necessary transition towards energy independence. “We design and install affordable solar systems with the highest yields. For your free consultation contact us today at huahinsolar@gmail.com. If you have anything less than a great experience with Solar Shop Hua Hin please call my cell.” Greg, Managing Director, +66(0)89 824 1963.