The main differences between monocrystalline and polycrystalline solar panels are their efficiency, color, shape, and material composition. Monocrystalline panels have solar cells made from a single silicon crystal, characterized by their black color and higher efficiency. Polycrystalline panels have cells made from multiple silicon crystals, with a blue color and a slightly lower efficiency.

Thin film solar panels are a less common type. They have a lower price than the two crystalline types, but this is offset by a much lower efficiency. This article will focus on monocrystalline and polycrystalline solar panels.

Before installing a solar power system for your home or business, you must decide which type of solar panel will be used. Polycrystalline panels are the most common, followed by monocrystalline panels. Both types use solar cells made from silicon, but their microscopic structure changes.

Do Monocrystalline and Polycrystalline Solar Panels Have the Same Quality?

Monocrystalline solar panels have a higher efficiency, but this does not mean that polycrystalline panels have a lower quality. The efficiency is determined by the material properties of solar cells, and should not be viewed as an indicator of product quality. If your solar panels are from the top global brands, both monocrystalline and polycrystalline panels are subject to stringent quality standards.

Comparing the two types of solar panels is similar to comparing a sedan with an SUV. High-quality cars of both types are available, but a compact car will have a better gas mileage thanks to its lower weight.

Since high quality is available with both types of solar panels, you can expect an excellent return on investment regardless of the type chosen. The best recommendation is purchasing panels in the Tier 1 list from Bloomberg New Energy Finance: they offer high quality, and they are supplied by companies with a solid financial condition. Having a good product is important, but you should also ensure the manufacturer will be around in the future, in case of a warranty claim. The Tier 1 list includes both monocrystalline and polycrystalline solar panels.

Choosing Between Monocrystalline and Polycrystalline Solar Panels

As mentioned above, quality is not an issue when comparing monocrystalline and polycrystalline panels. Assuming you have an available space that is not covered by shadows, both types will work well. However, monocrystalline solar panels become the best option under the following conditions:

• You have limited space for solar panels.
• Your priority is generating as much electricity as possible.

When space is limited, you cannot make your solar system larger to produce more electricity. The maximum production with the available space is only obtained with the more efficient monocrystalline panels.

Assuming space is not a limitation, you can use any type of solar panel. The best recommendation is getting quotes from multiple solar companies, to find the one that offers the highest return on investment and the quickest payback period.

If you plan to use all your available roof area for solar panels, you will probably have plenty of surplus generation around noon. All the electricity you don’t consume is sent to the power grid, and this may be viable or not depending on how the utility company gives credit. Assuming you fill the roof with solar panels, their surplus production will be higher if they are monocrystalline.

• Some power companies purchase surplus generation from your solar system at the retail price of electricity.
• However, other power companies only give partial credit for every kilowatt-hour sent to the grid by your solar panels.

If the local power company gives full credit for surplus generation, it makes sense to fill your rooftop with monocrystalline panels and maximize production. On the other hand, if you only get partial credit, you can use polycrystalline panels and take advantage of their lower price.

At the end of the month, the balance in your favor is subtracted from the power bill. By producing enough surplus electricity, it may be possible to reduce the power bill to zero. If the balance in your favor exceeds your power bill, the difference is normally carried to the next month. Some electric companies may also even pay you in cash, but this is less common.

Physical Differences Between Monocrystalline and Polycrystalline Solar Panels

Monocrystalline and polycrystalline solar panels differ in both appearance and efficiency. Their manufacturing processes have key differences, which are reflected in the final product.

The materials of a solar panel are the same in both cases: solar cells are made mostly from silicon, with small amounts of other elements. However, the structure of the silicon crystals changes depending on the type of solar panel. Monocrystalline panels have solar cells that are composed of a single silicon crystal, as implied by their name. On the other hand, polycrystalline panels have solar cells that are composed of multiple silicon crystals fused together.

• Monocrystalline panels are more expensive because their manufacturing process is more difficult. Molten silicon must be grown carefully into large crystals called ingots, which are then cut into individual solar cells.
• Polycrystalline panels have a less demanding manufacturing process, since there is no need to grow single crystals from molten silicon. Instead, silicon solidifies into a multi-crystalline block, which is then cut into individual solar cells.

Electric current travels more easily through monocrystalline cells, since they have an ordered crystal structure. On the other hand, polycrystalline cells have divisions in their crystal structure, which cause a slight disruption of electric current. This is exactly why polycrystalline panels have a lower efficiency. However, they are the most popular type because they are easier to produce and more affordable.

Monocrystalline and polycrystalline solar panels also differ in how their solar cells are cut, and this affects the appearance of the finished product. As mentioned above, monocrystalline solar cells are cut from single-crystal silicon ingots. Due to how the ingot is cut, these solar cells have an octagonal shape. On the other hand, the silicon wafers used for polycrystalline cells are made with square molds, and the solar cells have a square shape with straight edges. Polycrystalline solar panels have a lower cost for two main reasons:

• Their manufacturing process is simpler.
• Less silicon is wasted while cutting the wafers into solar cells.

The weight of the solar panel does not change much between the monocrystalline and polycrystalline types. Consider that both panel types use the same material, and what changes is the crystalline structure of silicon.

• The 60-cell panels that are commonly used in home solar systems weigh between 42 and 44 pounds each.
• On the other hand, the larger 72-cell panels weigh between 51 and 53 pounds.
• Therefore, the structural requirements for roofs are the same for both types of solar panels.

The color in solar panels is determined by how sunlight interacts with the solar cell materials. Since polycrystalline panels have solar cells made from multiple silicon crystals, sunlight spreads in multiple directions, causing a blue color and a shiny appearance. On the other hand, monocrystalline solar panels appear black because they absorb sunlight more effectively.

Manufacturer warranties and the expected service life are the same for both solar panel types. Normally, you can expect a 10-year or 12-year warranty against manufacturing defects. There is also a 25-year warranty against the loss of energy production. Solar panel manufacturers guarantee that energy production will not drop below 80% over a 25-year period.

Advantages and Disadvantages of Each Type of Solar Panel

When comparing monocrystalline and polycrystalline panels, it is not possible to say that one type is better than the other. The following table summarizes the advantages and disadvantages of each solar panel type:

In general, monocrystalline solar panels are a more expensive option to maximize electricity production with the space available. On the other hand, polycrystalline panels offer a more affordable option when space is not a limitation.

Comparing Monocrystalline and Polycrystalline Panels: A Simple Example

If you ask for a specific solar system capacity, such as 10 kilowatts, polycrystalline panels will tend to use more space. Since these panels have lower efficiency, they need to cover more space than monocrystalline panels. However, keep in mind that polycrystalline panels also have a lower cost.

As an example, assume you are comparing the two following solar panel options for a 10-kilowatt installation:

• 275-watt polycrystalline panels, with a retail price of $250 each
• 305-watt monocrystalline panels, with a retail price of $340 each
• Both options have 60 cells, and they have the standard solar panel size of 65” x 39”.

You need 37 of the polycrystalline panels to reach 10 kW of capacity, but you only need 33 of the monocrystalline panels. In other words, you need four additional panels if they are polycrystalline, and the solar system will cover 12 percent more area.

Each solar panel covers around 17.6 square feet. You will cover around 652 square feet with the polycrystalline panels, and around 581 square feet with the monocrystalline panels. However, this is not an issue if you have abundant space. On the other hand, if you only have 600 square feet available, you can only reach 10 kW with the monocrystalline panels.

With the data in this example, the total price of the 37 polycrystalline panels is $9,250. On the other hand, the 33 monocrystalline panels cost $11,220. In this case, one monocrystalline panel is 36% more expensive than one polycrystalline panel. However, reaching 10 kilowatts is only 21% more expensive with monocrystalline modules, since you need less of them.

Keep in mind this is just an example, and solar panel prices vary depending on the model, manufacturer, and project location. In the US you can expect to pay less than $1 per watt if the panels are polycrystalline, and above $1 per watt if they are monocrystalline. Lower prices are possible in large-scale solar systems, such as those in commercial and industrial buildings.

In home solar systems, the cost of solar panels is only around one-third of the total project cost. Consider that panels also need racking for support, as well as inverters, which convert their electricity output into the AC power used by home appliances. A solar power system also requires electrical protection devices, which protect your investment from short circuits and other electrical faults. These costs are similar for monocrystalline and polycrystalline panels.

Each solar panel can be expected to produce between 400 and 600 kilowatt-hours per year. The exact electricity production depends on the panel specifications and the amount of sunshine received. Smart design decisions can also improve the productivity of a solar power system.

Assuming that sunshine does not change, there are two main ways to increase the amount of energy a solar panel produces:

• Making the panel larger, to capture more sunlight.
• Achieving a higher efficiency with an improved solar panel design.

Solar panel manufacturers prefer to work with standard sizes, since this simplifies fabrication. For this reason, you will find that most panels have either 60 or 72 solar cells. Current research focuses on improving cell efficiency to increase energy production with the same panel sizes.

How much energy a solar panel produces depends on several factors. Solar panel efficiency and size are important, since they determine how much sunlight is captured and converted into electricity. Solar productivity also depends on the local climate, since more sunshine translates into a higher energy output. Finally, the panel orientation affects the amount of sunlight hitting its surface. The best solar companies make sure that no panels are covered by shadows, while finding the orientation that captures the most sunlight.

What Is the Average Wattage of Solar Panels?

The power rating of solar panels is commonly misunderstood. All panels are tested under equivalent laboratory conditions, and the resulting wattage becomes their rated power. However, the operating conditions in actual projects differ from the ideal lab scenario, and energy production also varies.

Solar panels with 60 cells normally have a wattage in the range of 250 to 350 watts. Some 72-cell panels go above 400 watts, since they have 12 additional solar cells producing electricity.

The controlled laboratory conditions for panel wattage tests differ from those found in most project sites. However, the power rating gives an idea of how solar panels compare with each other. A 360-watt panel will tend to produce around 20% more energy than a 300-watt panel, even if they don’t operate at their rated wattage in actual projects.

Based on the efficiency of the average solar panel, you can expect to convert between 15% and 20% of sunshine into electricity. However, some of the most efficient solar panels available go above 22%.

How Solar Panel Specifications Affect Energy Production

The productivity of solar panels depends on site conditions and the properties of the panels themselves. Site conditions cannot be changed, but the panels can be positioned to get maximum sunshine. With respect to the panels themselves, energy production is strongly dependent on the following specifications:

Panel size

A 72-cell panel has 20% more area than a 60-cell panel, thanks to the 12 additional solar cells. They are more productive simply because they capture more sunlight.

Panel material

Assuming the same size, monocrystalline panels have the highest energy production, followed closely by polycrystalline panels. Thin-film panels produce the least energy per square foot.

Temperature coefficient

Solar panels lose wattage as temperature increases, and this is represented as a percentage loss per degree Celsius. Thin-film panels are the least affected, with losses under 0.30% per °C. On the other hand, mono and polycrystalline panels normally lose over 0.40% power per °C.

Consider that performance loss with temperature is a temporary effect, and it does not represent permanent damage. When the temperature drops, panels recover their lost wattage.

You will notice that 60-cell panels are rated at 20 volts, while 72-cell panels have 24 volts. This data is used by solar installers to design electrical connections, but wattage is the value that matters when estimating the amount of energy produced. Under equal conditions, a 20V 350W panel will have the same productivity as a 24V 350W panel.

Solar panel specifications can change a lot from vendor to vendor, but the way they function stays the same. Installation costs are roughly equivalent for all types.

How Much Electricity Do Solar Panels Produce Each Year?

Solar panels are characterized by their versatility. They can be used in nearly all buildings and climate zones, as long as the following conditions are met:

• Having a roof with enough structural capacity for the panels, or a large enough property for a ground installation.
• The prospective area for solar panels should not have serious shading issues. Solar panels produce a lot more energy when there are no shadows.

How much electricity does a solar panel produce? An accurate answer is only possible if a solar company inspects your property, to then design a suitable solar power system. However, there are online solar calculators that provide a broad estimate of production based on your geographic location and electricity consumption.

When comparing sites, a very useful metric is the yearly kilowatt-hour production per kilowatt of installed capacity, or kWh / kW.

• For example, if your home solar system has an installed capacity of 10 kilowatts, and the output in year was 14,500 kWh, you are getting 1450 kWh per kW.
• This production rate increases in sunny locations, since there is more solar radiation that can be converted to electricity.

NASA and other scientific institutions have compiled solar productivity data based on location. The SOLARGIS website has solar productivity maps for over 180 countries, and you can check the expected kilowatt-hour production for every kilowatt of solar capacity.

Annual Productivity with Various Solar Panel Wattages and Sunshine Conditions

The following table estimates the kilowatt-hours a solar panel can produce per year, considering five panel wattages and five sunshine conditions:

This table provides an idea of what production to expect from a single solar panel, based on wattage and the local sunshine. However, only a solar company can provide an accurate estimate. A solar system design considers factors like rooftop orientation and the presence of shadows, which are unique for each site.

Solar productivity values in kWh per installed kilowatt normally include the conversion from direct current to alternating current. The DC power output from panels is not suitable for home appliances directly, and it must be converted to AC by an inverter. The best solar inverters have an efficiency of over 97%, but losses are unavoidable because no energy conversion system is perfect.

Since solar panels only operate at rated wattage in laboratory settings, you will find that the inverter is specified smaller than the total wattage of solar panels. For example, you may find that a 5-kW inverter is connected to panels that add up 5.5 or 6 kW of capacity. This may seem like a design mistake at first, but actually it is the best decision:

• Solar panels operate below their rated wattage most of the time. A larger inverter would simply be wasting capacity while being more expensive.
• Inverters can “clip” any solar production that exceeds their capacity. They will not be damaged if there is a sudden peak in the amount of power from panels.

How Much Electricity Does a Solar Panel Produce per Month and per Day?

The annual productivity of solar power systems is relatively constant. However, the monthly productivity is more variable due to the effect of the seasons. As you might expect, solar panels are more productive in summer and less productive in winter.

Using an example from the table above, a 360W panel will produce around 684 kWh per year in a site that offers 1900 kWh/kW. On average, this is equivalent to 57 kWh per month and 1.87 kWh per day. However, the monthly and daily productivity will be above the average value during summer, and below the average value during winter.

Having a higher productivity during the summer months is actually useful, since that is when air conditioners operate at full capacity. The additional power consumption of air conditioners can be offset by the extra production from solar energy systems.

Solar offers from the best companies will normally include production estimates by month. These can give you a better idea of how the productivity of your solar panels will change throughout the year.

Why Solar Panel Output Matters

The productivity of panels is important when designing solar systems, since it determines how many are needed to reach a certain energy production target. When the square feet available are limited, getting the highest possible output from each panel is important.

The sufficient number of solar panels needed to power your home depends on your electricity consumption and savings goal. For example, reducing a power bill by 80% requires more panels that reducing it by 50%. If energy storage is added to use electricity from solar panels at night, the production calculations must also consider the kilowatt-hours required to charge batteries.

Solar shingle installations follow a completely different approach, since solar cells are embedded in roof shingles. This makes them worth installing in new homes, since there is no need to install a separate roof and solar energy system. Conventional solar panels are still the best option for existing homes. Solar shingles would require a complete roof removal in this case, which is very expensive.

Most solar panels are manufactured from silicon. Depending on how silicon is processed, it can be monocrystalline, polycrystalline, or amorphous. Crystalline panels are the most common, while amorphous silicon panels are part of the “thin-film” category, which is used less.

Solar panels generate electricity without moving or producing noise, making them an excellent renewable energy source for buildings. Nobody is exposed to heavy machinery in movement, and the distracting effect of noise is prevented. With these unique features, one of the first questions asked by home or building owners is: “what are solar panels made of?”.

All monocrystalline and polycrystalline panels are made from silicon, but thin-film panels can be produced with other substances. The materials used in solar roofs of the thin-film type include cadmium telluride (CdTe) and copper indium gallium diselenide (CIGS).

Processing Silicon into Solar Cells

By itself, pure silicon does not produce electricity under sunlight. However, other elements can be added in small amounts to achieve this effect. Adding phosphorus produces a surplus of electrons to carry electricity, and the result is N-type silicon. On the other hand, the addition of boron or gallium causes an electron deficit, and the product is called P-type silicon. When both types of silicon are arranged in layers, light induces an electron movement between them, producing an electric power output.

Pure silicon is not found in nature, and instead it must be obtained from silicon dioxide, which contains impurities. Silicon dioxide is melted, and unwanted elements are removed with physical and chemical processes. Once the silicon has been purified, it is converted into N-type or P-type silicon by adding other elements in controlled amounts.

Amorphous silicon is the type used in some thin-film panels, and it gets its name because the molecular structure is not crystalline.

How to Identify the Different Types of Solar Panels

The language used when describing the types of solar panels may sound very technical. However, the three main types can be easily identified based on their appearance.

If a panel has a grid-like surface that is separated into solar cells, it belongs to one of the crystalline types. Monocrystalline panels use only one silicon crystal per cell, and they are characterized by their black color. On the other hand, polycrystalline cells are made of multiple crystals, and they have a lighter blue tone. Solar cells are produced from molten silicon in both cases. However, monocrystalline cells demand more process control to ensure they are made from a single crystal.

Identifying thin-film panels is even easier, since they have a uniform surface without divisions. This is due to their manufacturing process, where the solar material is deposited in layers rather than individual cells.

Before choosing between the solar panel types, the first step is understanding how they work. Consider that electricity is only produced when sunlight is available, and the maximum production is only achieved around noon. If you want to use solar energy 24/7, you must add battery storage for the night or cloudy days.

Comparing the Types of Solar Panels: Advantages and Disadvantages

The different types of solar panels have pros and cons, like in most other decisions that deal with technology.

• Monocrystalline panels are the most efficient, which means the production of electricity per square foot is higher. Therefore, these panels are the best option if you have limited space for the solar energy system. However, monocrystalline panels are also the most expensive, since they are the most difficult to produce.
• Polycrystalline panels have a moderate efficiency, but they are also more affordable than monocrystalline panels. They are also the most common type.
• Thin-film solar panels have the lowest cost and weight. However, they are also the least efficient panels, having the lowest electricity production per square foot. In other words, thin-film panels need more space than crystalline panels to reach a specified capacity. All three types of solar panels lose performance when they heat up, but thin-film panels suffer less from this effect.

The costs associated with installation are similar for all types of solar panels. Thin-film panels are easier to handle thanks to their low weight, but you also need to install more of them. Polycrystalline and monocrystalline panels are similar in terms of weight and size.

The appearance of solar panels is a subjective factor, but it can also influence purchasing decisions. While some users may like the smooth surface of thin-film panels, other may prefer the traditional appearance of crystalline panels. All three types of solar panels achieve good results when installed by a qualified company. However, if you prefer thin-film panels, make sure you have the roof space to accommodate a larger installation.

The solar panel buying information provided by manufacturers contains many details about the panel type and efficiency. Solar installers use these technical specifications to select the best option for your property.

Additional Materials Needed to Produce Solar Panels

Silicon solar cells are the core of solar panels, but other materials are needed to allow their use in outdoor settings. Solar cells are protected by a housing, which is normally produced from aluminum or fiberglass. Also, the side of solar cells that faces the sun is covered by glass, so sunlight can reach them. Most commercial solar panels use either 60 or 72 cells per unit.

Solar panels also have internal wiring, since the solar cells must be connected together to gather their electricity production. The connection terminals of a solar panel are really the ends of a circuit that connects all the cells inside.

It is important to note that solar panel manufacturing methods have evolved over time. At first, solar power was regarded as a technology for satellites and other outer space applications. Therefore, manufacturers focused on lightweight designs. When solar power became a viable electricity source for homes and businesses, panel designs became more robust and durable.

High-quality solar panels last more than 25 years, and their payback period is only between 4 and 8 years. If you purchase panels with a solid warranty, the return on investment is assured. However, keep in mind that warranties are only valid if the panels are installed properly. Working with a qualified solar installer is strongly recommended.

Installing solar panels is one of the most effective ways to reduce your electricity bills. They may seem expensive at first, but their long-term savings are greater than their upfront cost. In other words, every dollar spent on a solar power system is recovered tenfold. After understanding how long solar panels last, it makes complete sense as an investment.

Understanding the Two Types of Solar Panel Warranties

When purchasing warranties, you will notice there are two types. One of them covers manufacturing defects, while the other covers electricity production. Each warranty protects your investment from different issues.

The warranty against manufacturing defects is normally for 10 to 12 years. If your solar panels are correctly installed and any of them fail, this warranty gives you replacements at no cost. Just keep in mind that the faulty panels must be removed and replaced, so make sure your solar provider offers support.

The energy production warranty is much longer, and leading solar manufacturers offer 25 years or more. Solar panels degrade over time like any power generation system, but this warranty covers you if they degrade faster than normal. High-quality panels will have at least 80% of their initial capacity after 25 years, and many warranties use this value.

• A panel with a power rating of 330W will have dropped to 264W after 25 years.
• If you use 20 of them in a 6.6-kilowatt system, the capacity after 25 years will be 5.28 kW.

Warranties are only useful if the manufacturer will be around in the future to make them valid. The best recommendation is purchasing panels from Tier 1 solar manufacturers: they offer quality products while being companies with financial health. Your solar warranty becomes useless if the manufacturer goes bankrupt!

Like with any other product, high-quality solar panels from top brands tend have a higher price. However, they are worth it when you consider performance and warranty coverage. Panels can last even longer than their 25-year warranty with adequate maintenance. However, keep in mind that energy production will wane over time, even with top-tier panels.

The long warranty period is one of the main factors that makes solar panels a good investment. Since the typical payback period is shorter than the warranty period, your power bill savings are assured. Just be warned that warranties are voided by an incorrect installation, hence the importance of working with a qualified installer.

Do Solar Panels Save Less Electricity over Time?

Due to the degradation rates of solar panels, you may be thinking that electricity savings will shrink each year. However, consider that kilowatt-hour prices tend to increase over time.

• If your panels lose 0.8% of their capacity in a year, but the local power company raises its tariffs by 3%, your electricity savings will increase.
• According to a research project by the National Renewable Energy Laboratory (NREL), most panels degrade at a rate of less than 1% per year.

When solar companies estimate the electricity savings and payback period of a solar energy system, they consider degradation rates. In other words, solar panels are a good investment even with their loss of production over time. Solar panel roofs have become popular for the simple reason that they make financial sense.

If you are planning a home addition in the future, you can simply increase the number of panels. This way, they can keep up with your electricity needs. You must only make sure that the additional panels are compatible with the original installation. You can also ask your solar installer to leave the provisions for an eventual expansion.

How Long Do Solar Inverters and Batteries Last?

Consider that the panels are only one part of an operational solar power system. Components like racking and wiring are very durable, and you can expect them to last as long as the panels. However, solar inverters have a shorter service life than panels, and you must plan for an eventual replacement. The same applies for batteries, in case your solar power system uses them.

Due to the way they work, solar panels produce electric power in the form of direct current (DC). However, your home appliances need alternating current (AC), which is the type of power provided by utility companies. Solar inverters gather the electricity produced by panels, converting it into AC power. However, the life expectancy of an inverter is only around 10 years, which means your panels will eventually need a new one.

The quality of your inverter is just as important as the quality of your panels. The leading inverter suppliers normally offer a 10-year warranty, similar to the panel warranty against manufacturing defects.

A solar power system can work without batteries, making them an optional component. However, they bring additional benefits when present:

• You can store solar energy for nighttime and cloudy days, which means you rely even less on the local power company.
• The battery system can assume the role of a backup generator during a blackout.

Lithium-ion batteries are now available with a 10-year warranty. Conventional lead-acid batteries last much less, normally between 1 and 3 years. Lithium-ion batteries are also more flexible and efficient, while lead-acid batteries must be fully charged between discharging periods.

The shorter service life of inverters and batteries does not mean they have a lower quality than solar panels. That is simply the current development stage of those technologies, and it is likely that more durable versions will be available in the near future.

Do Solar Panels Need Maintenance?

Compared with other renewable energy systems, solar panels have simple maintenance needs. If they are kept clean and protected from damage, a long service life is assured. In addition, since the panels don’t have moving parts, they are not exposed to mechanical wear.

Solar providers follow different procedures when calculating the cost of solar panels. When you receive offers, ask the providers about solar maintenance services. In fact, some companies may include a period of free maintenance after installing the solar system.

If you get solar power through a lease or Power Purchase Agreement (PPA), the contract will normally make the provider responsible for maintenance. This includes inverter and battery replacements after around 10 years, so you don’t have to plan and budget that purchase. In solar leases and PPAs, the price to pay for these benefits is sharing your savings with the provider.

Like any electrical device, solar panels must be protected with suitable circuit breakers. Panels without adequate electrical protection are more vulnerable to faults, and there is also a higher risk of fire or electric shock. However, this aspect is covered if your system is designed and installed by a qualified solar company.

Consider that 25 years is a long time, and your home surroundings can change. For example, trees around your home can cast shadows on the panels or on your solar panel roof, reducing their energy production. Avoid planting trees in locations where they can cause shading issues for your solar energy system, and make sure you trim any branches that block the sun.

Solar panels work by converting sunlight into electricity at the atomic scale. When solar cells are struck by light, they produce a flow of electrons, or electric current. Since this process happens at such a small scale, it is invisible for humans. Compared with other renewable energy systems, panels are characterized by their lack of movement.

Solar panels produce a certain amount of energy that is determined by two main factors: the amount of sunlight reaching the panel, and the material composition. Some panel materials can collect more sunlight per square foot, leading to a more efficient and compact installation.

Solar panels have become a popular renewable energy option for homes and businesses, and this makes perfect sense when you weigh their costs and benefits. Solar power systems become more affordable each year, while electricity costs continue to rise. From a financial standpoint, adding panels to a building is an excellent investment. In this article we will be answering the common question of “how do solar panels work”?

How Exactly Does a Solar Panel Work?

A solar panel can be viewed as the opposite to an LED bulb, which is also an electronic device that uses semiconductor materials. Just like an LED bulb converts electricity into lighting, a solar panel absorbs light to produce electricity. This behavior is called the photoelectric effect, and it was first studied in the 19th century.

The name of solar panels can be misleading, since they work with any type of light. If you place a panel under an artificial bright light, it will start to produce electricity. However, only sunlight is a viable energy input, since it is delivered for free. Other light sources have either a fuel cost or an electricity cost.

The material used to make solar panels is normally silicon, which has many applications in the electronics industry. With a special chemical process, silicon can be treated so it will produce electricity in response to ligh541t.

• Energy conversion begins when a solar cell is hit by photons, which are the elemental particles of light.
• Photons separate electrons from the silicon atoms, and the movement of electrons is equivalent to electric current.
• The combined movement of electrons from multiple solar cells provides the total output of a solar panel.
• The concept is then repeated when the panels are wired together, adding up their individual production.

Producing electricity without moving is a significant advantage of solar power systems. Other generation systems like wind turbines and diesel generators have moving parts, which are subject to mechanical wear. In these cases, the constant need for lubrication and part replacements makes maintenance difficult. Taking care of solar power systems is much easier, since the most demanding maintenance task is keeping their surface clean.

Why Are Solar Panels Connected to an Inverter?

You may have noticed that panels are not connected directly to home appliances. Instead, they are wired together and their electricity production passes through an inverter. This is necessary because the electricity produced by panels does not have the properties required by home appliances.

Solar panels produce direct current (DC) electricity, while home devices use alternating current. A DC power source provides a constant voltage, while an AC source has a voltage that oscillates between positive and negative. Electric companies use AC power because it provides many advantages in electricity generation and transmission.

Basically, a solar inverter converts the DC output of panels into an AC power supply that is suitable for home appliances. Since the power grid also uses AC voltage, it can be synchronized with the solar power system. This has several advantages:

• When solar power production is not enough for home appliances, any additional electricity can be drawn from the grid without changing any connections.
• Surplus production can be exported to the grid, to be subtracted from your power bill.

When a solar power system is synchronized with the power network, it is called a grid-tied installation. This is the most affordable system configuration, and also the most common.

What are the Different Types of Solar Panels?

As previously mentioned, solar panels use materials that produce electricity when exposed to light. Most panels are made of crystalline silicon cells that are wired together to add up their voltage. Typically, a panel will have either 60 or 72 cells.

• A 60-cell panel has 10 rows of six cells.
• On the other hand, a 72-cell panel has 12 rows of six, making it 20% longer.
• The amount of solar panels needed for a specific building will change depending on the type. Since 72-cell panels have more cells, they typically have a higher wattage.

60-cell panels are more common in the residential sector, while 72-cell panels are more common in business applications and solar farms. Nothing limits the use of 72-cell panels in home solar systems, but their larger size can be an issue when roof space is limited. 60-cell panels can be used without problem in large commercial buildings as well, but the need to use more of them can increase labor costs.

Crystalline silicon panels can be classified into two subtypes. Monocrystalline panels have solar cells made from a single silicon crystal, and their surface is black. On the other hand, polycrystalline panels have blue cells that are made from several crystals. The efficiency of solar panels is higher if they have monocrystalline cells, but their price is also increased.

Some panels do not have silicon cells, and instead they have a uniform surface. These are called thin-film panels, since the material that converts sunlight into electricity is deposited as a layer.

• These panels have a lower cost that the crystalline ones, but they also need more space to compensate for their lower efficiency.
• The cost per watt of capacity ends up being similar since the panel has a lower cost — but you need more of them.

Monocrystalline, polycrystalline, and thin-film panels are the three main options available, and the polycrystalline ones have dominated the market. Solar shingles are emerging as a fourth option. They combine roof shingles and panels into a single element.

Understanding the Cost of Installing Solar Panels

The panels themselves only represent a fraction of the cost of a complete solar power system. The costs involved when installing solar panels include special racking, the solar inverter, and electrical protection devices. When all solar costs are factored in, you can expect to pay $3 per watt of capacity in the United States.

As previously discussed, an inverter converts the output of panels into AC power for home appliances. Special racking is used to attach the panels to the roof, since they are not designed for direct installation. Also, solar panels need circuit breakers like any other electrical device. Electrical faults such as short circuits and ground faults can severely damage solar panels and their associated components.

Knowing how to install solar panels has become a useful asset in the United States job market, due to the high demand for solar systems.

Managing Solar Energy Production Effectively

Solar power is clean, and its cost continues to drop each year. However, solar systems still have a limitation that is shared with wind turbines: they depend on variable energy inputs to produce electricity. For this reason, you cannot go off-grid with solar panels alone, and batteries become necessary for nighttime and cloudy days.

Governments and power companies have developed and interesting concept to manage the variable nature of solar power, which is called net metering:

• Surplus energy production from your solar energy system can be exported to the grid.
• The power company gives credit for that energy on the next electricity bill.

With net metering, your home can get savings for unused solar energy production. If your solar system is large enough to produce surplus electricity at noon, it can be exported to the grid and deducted from your nighttime consumption.

Solar panels work better when they receive direct sunlight. They can be mounted on tracking mechanisms to always face the sun, but this approach is only recommended when space is a limitation. In most cases, adding more panels is a better option than using a few panels with a solar tracker.