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The Efficiency Of Solar Panels

If you seek cleaner energy sources, harnessing the sun's power for electricity is perhaps one of the best options for you. While the promise of lowering your monthly energy costs by utilising the most recent advancements in solar innovations may seem appealing, the initial cost of solar system installation might make you wonder whether solar power is indeed worth it.

First, you should consider the efficiency of the solar panel you pick. However, this does not mean that a more efficient solar panel will result in better financial advantages for you personally. This article will help you understand how you and others could benefit directly from a solar energy system installation and how to select the most efficient solar panels suitable for your needs.

If converting to a solar power system is ideal for your business or house, you will have to consider panel installation, your geographic location, the architectural design of your property's roof, temperature, and the degree of shade on your building. Bear in mind that the measure of energy output in a particular surface area in solar panels is known as efficiency. The more efficient a cell is in producing energy, the less space it requires on your roof.

How Efficient Are Current Solar Panels?

Nowadays, most solar panels are around 15% and 20% efficient, with exceptions on either end of the spectrum. Super-efficient solar panels can surpass 22 per cent efficiency in some situations (and nearly approach 23 per cent). However, the vast majority of photovoltaic solar panels on the market are less than 20 per cent efficient.

Highly efficient panels are pricey, but they will aid you in fulfilling your power needs, mainly if your roof is small or you have limited space. When the same quantity of sunlight hits two high-efficiency panels with varying efficiency ratings for the same amount of time, a more efficient panel will give a more significant energy output than a less efficient panel.

Solar panel efficiency is determined by the efficiency of its solar cells, which is impacted by its composition, the electrical architecture, surrounding components, and other factors. As previously mentioned, the amount of sunlight that falls on every cell transformed into energy is called solar cell efficiency.

If there are two high-efficiency panels of the same physical size, with one having a 21 per cent efficiency rating and the other 14 per cent efficiency rating, the one with 21 per cent efficiency will produce 50 per cent more kilowatt-hours (kWh) of power. This is the case if it operates under the very same conditions as the panel with 14 per cent efficiency. As a result, having a solar panel with higher efficiency is critical in maximising power usage and energy bill savings.

Do not be worried if your solar panels efficiency rates appear to be a little low at first sight. With the introduction of new technology and industrial capacities, the threshold for efficiency will only rise in the coming years. In fact, by adopting multi-junction cells designed to catch multiple frequencies of light, scientists have attained a record of around 40 per cent efficiency. However, current panel options produce enough usable energy for most homeowners and businesses in the meantime.

How Solar Panel Efficiency Is Calculated

Cell efficiency is determined by dividing the maximum wattage of your solar system by the product of the square footage of your solar panels and its incident radiation flux, both multiplied by 100. Incident radiation flux refers to the degree of light shining on the earth's surface in your location.

Basic solar panel testing settings assume an incident radiation flux of about 2,000 watts per square metre. Assume you want to determine the efficiency of a 400-watt solar panel. If your panel is 2 square metres in size and you assume basic testing conditions, that equates to 2,000 watts. If you divide that amount by 400 and multiply it by 100, you get a 20 per cent efficiency rating.

What Determines Solar Panel Efficiency?

Several factors determine a solar panel's efficiency. First and foremost, the efficiency of your solar panel cell is influenced by how much incoming sunshine the cell can transform into valuable electricity. But what elements influence that final conversion rate? When engineering and manufacturing high-efficiency solar technologies, photovoltaic cell scientists and manufacturers take the factors that significantly affect the efficiency of a panel into account. These include:


Even a minor shadow on a single solar panel might reduce the overall efficiency of your solar system. While panel manufacturers do not take shade into account, it is a crucial aspect to consider and, if necessary, avoid while installing solar panels.


Your panel efficiency might be favourably or negatively impacted depending on the area you live in and the sort of weather constantly present. Solar cells, for example, stop operating if more than five millimetres of snow build on the panel. On very windy days, minor declines in inefficiency can also be observed.

Wavelength/frequency of light

Light is composed of photons, which vibrate at various frequencies and make up both visible and invisible light coming from the sun. Depending on the frequency and wavelength of the photons, some are reflected, and others pass directly through. In the same vein, others are absorbed when they strike the surface of your PV cell.

Some of the absorbed light will be converted to heat, whereas the remaining photons have enough energy to free electrons from the atomic bonds, resulting in an electric current. The greater the range of photons, including infrared, ultraviolet, and 'visible range' that your solar system will absorb, the greater the efficiency of the solar cell.

Angle and positioning

Proper solar panel installations and an optimal angle are critical for capturing the highest amount of sunlight.


Higher temperatures reduce power output and efficiency. That's why specific solar panels are specifically designed for warmer climates.


The material used, such as monocrystalline silicon or polycrystalline silicon, cadmium telluride, thin-film, etc., influences how light is converted to electricity.

Wiring and cabling

The arrangement of wires and "busbars" on a panel that captures then transfer electricity also has an impact on the panel's efficiency.


The effectiveness of a solar panel may be reduced if the light is greatly reflected away from it. That is why the glass layer covering the top of silicon solar cells is critical. Furthermore, factors such as the ability to absorb light on either side of a cell (bifacial solar panels) and the ability to absorb light at different wavelengths (multijunction solar panels) alter the efficiency equation for a solar panel. Overall, scientists and researchers have a myriad of levers at their disposal when striving to improve the efficiency of a solar panel cell.

Is It True That Solar Panels Degrade Over Time?

Solar panels, like most technology, will produce less energy with time. The reduced energy output is referred to as the degradation rate. The average panel degradation rate is around 0.5 per cent per year, which indicates that the energy output of a solar panel will drop by 0.5 per cent every year.

Your solar panels should still produce around 90 per cent of their original output after about 20 years. While solar energy systems can last up to 20 years, fixing and replacing them can be costly, so you need to take great care of your panels.

Tips For Increasing The Efficiency Of Solar Panels

While solar panels are relatively low-maintenance, it is nevertheless necessary to maintain and monitor their functioning regularly. Here are a few pointers to guarantee your solar system is always performing at its best:

Engage with a reputable solar company

Finding a professional to install your solar system is the best way to guarantee its durability. Even though solar systems need little regular maintenance, great solar companies offer complete maintenance packages throughout the life of their systems to ensure that they continue to create clean, economical, and reliable electricity for decades.

Keep your panels free of debris

While rain is usually enough to keep your solar panels clean, you should consider hiring a professional to clean them if you notice that your panels aren't performing to their maximum potential.

Ensure your panels are checked and serviced regularly

If you notice that your panels underperform after it rains or after they are hosed thoroughly with water, or you see an unusual increase in your electricity bill, it could signify an electrical issue that requires professional attention. You should ensure that your panels are checked and serviced regularly by a professional.

How To Clean Your Solar Panels

To clean your panels, get yourself some solar panel cleaning kits first, as it makes the task considerably simpler. A biodegradable cleaning soap, a wiper, and a small brush, plus a brush with a long handle, are included in the kit.

Step One: Combine soap and water in a bucket

In a bucket, combine the soap and water (the soap bottle should contain instructions on how to use it).

Step Two: Carefully wipe each panel

Now, carefully wipe your solar panels with the brush that has been dipped in the bucket.

Step Three: Rinse each panel with water and a soft brush

Then, rinse the panels using clean water and a soft brush to eliminate any filth or grime that has accumulated.

Note: If you clean your solar panels with an abrasive sponge or soap, you risk scratching the glass. The most straightforward approach to cleaning your solar panels is with a soft brush or biodegradable soap. When cleaning solar panels, it's also vital not to use harsh chemicals because they can damage solar surfaces and solar panels are expensive to replace.

How Geographic Location Affects Solar Cleaning

Your geographical location impacts how to clean your solar panels and how frequently they have to be cleaned to stay efficient. Generally, you should clean around your solar panels once or twice a year. However, in some places, regular cleaning might be more helpful.

Sand accumulates on PV panels in desert areas, such as some regions of Australia, where the climate is dry and dusty, blocking light and scratching the surface. Wildfire ash can swiftly fall on panels in big clumps in places like California and a few areas of Australia that are prone to wildfires. This means that you need to clean your solar panels more regularly if you reside in such settings.

PV panels situated in polluted places, such as near industries, highways, or even airports, will encounter significant amounts of atmospheric grime, including oil build-up. If you live in one of these places, you should regularly examine your solar panels' surface condition and wash them periodically.

In addition, leaves are more likely to fall on the panels in installations with many trees nearby, obscuring sunlight absorption. Birds are also attracted to trees, leading to a build-up of droppings that cover the PV cells and harm the surface because of acidity, lowering the panel's efficiency.

Different Solar Panel Types

There are different solar panel types, and the design of each type of solar panel varies due to variances in materials and production. The various solar panel types are as follows:

Solar panels with monocrystalline crystals

A solar panel is a monocrystalline one if it has black cells. Because of the way light interacts with its pure silicon crystal, the cells look black. While the solar cells themselves are usually black, the back sheets and frames of monocrystalline solar panels come in a variety of colours. The solar panel's back sheet is typically black, silver, or white, while the metal frames are usually black or silver.

Monocrystalline panels are the most efficient and offer the most powerful capacity. They may achieve efficiencies of more than 20 per cent, while polycrystalline panels often achieve efficiencies of 15 to 17 per cent. Monocrystalline solar panels produce more energy than other types of panels due to their efficiency and because they are also available in greater wattage modules. Most monocrystalline panels have a power capacity of more than 300 watts, with some models recently exceeding 400 W.

Monocrystalline solar panels are probably the most expensive of all kinds of solar panels. This is primarily due to the production process: because the solar cells are made up of a single silicon crystal, producers must pay the costs of making these crystals. This technique, known as the Czochralski process (CZ), consumes a lot of energy and wasted silicon.

Solar panels with polycrystalline crystals

Unlike monocrystalline solar cells, polycrystalline solar cells exhibit a bluish tint due to light reflecting differently off the silicon fragments in the cell than it does off a monocrystalline silicon wafer. Polycrystalline panels, like monocrystalline panels, feature distinct coloured back sheets and also frames. Their frames are usually silver, whereas their back sheets are either white or silver.

Solar panels made of polycrystalline crystals are often less expensive than monocrystalline panels. This is because the cells are made up of silicon fragments instead of a single silicon crystal. This enables a considerably more straightforward cell production process, saving both producers and end-users money.

Using lower efficiency, low-cost polycrystalline panels can save money upfront for property owners with a lot of space for solar panels. On the other hand, installing high-efficiency monocrystalline solar panels is a good option if you have limited space and want to save money on your electric bill.

Thin-Film solar panels

The technology's thinness and low profile are the most distinguishing aesthetic features when it comes to thin-film panels. As their name implies, thin-film panels are usually thinner than other panel types. The cells in these panels are approximately 350 times thinner than crystalline wafers employed in polycrystalline and monocrystalline solar panels.

While thin-film cells could be much thinner than normal solar cells, a thin-film panel's overall thickness may be similar to that of a monocrystalline or even polycrystalline panel if it has a thick frame. Thin-film solar panels come in a variety of colours, including blue and black, depending on the material they're made of. They are less efficient and have lower power capacity than monocrystalline and polycrystalline panels.

Efficiencies vary depending on the type of material utilised in the cells, although they usually are about 11 per cent efficient. Unlike monocrystalline or polycrystalline solar panels, which are available in standardised cell sizes of 60, 72, and 96, thin-film technology does not. As a result, the power capacity of one thin-film panel will be substantially determined by its physical size. Monocrystalline and polycrystalline solar panels will, on average, have a higher energy capacity per square foot than thin-film panels.

Even with higher labour needs, the overall cost of installing a thin-film solar panel system may be cheaper than installing a monocrystalline or a polycrystalline panel system. Thin-film solar panels require less labour to install as they are lighter and easier to handle. This makes it much simpler for installers to lift these panels onto roofs and secure them in place. This, in turn, translates to lower labour expenses, contributing to a more affordable solar installation overall.

Contact A Reliable Solar Company

Solar power systems harness the sun's clean, pure energy. Installing solar energy systems in your home or business will help reduce greenhouse gas pollution and reliance on fossil fuels. Electricity is traditionally generated using fossil fuels like coal or natural gas. If you own a large private house or a business, electricity expenditures can account for a significant amount of your monthly expenses.

With a solar panel system, you'll acquire free electricity for the system's life, which may be up to 25 years. Even if you don't produce 100% of the power you need, solar reduces your electricity bills, resulting in significant savings. If you want to begin your journey to clean energy by installing solar panels, contact a competent and reliable solar company to help you choose the best solar panel for your business or home and do the installation.