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What’s the Ideal Solar Module for Outdoor Use?

A monocrystalline panel is the perfect option for a solar module intended for outdoor usage. Due to its efficiency of 20%-25%, it performs better in low-light conditions, generating up to 12% more power in cloudy weather. Monocrystalline systems require 30%-40% less space than polycrystalline and therefore offer more space-effective solutions to outdoor installations.

Efficiency of Monocrystalline Panel

The photoelectric conversion efficiency of monocrystalline panels is usually between 20%-25%, while the efficiency of polycrystalline solar panels on the market is mostly between 15%-20%. A roof installed with monocrystalline panels can generate about 30-35 kWh of electricity per day, while polycrystalline panels of the same area may only produce 25-28 kWh.

Whereas the general size for a 5 kW monocrystalline solar system already requires 30 m² of rooftop, the same capacity for a polycrystalline system needs 40 m² or even more. Monocrystalline panels currently account for more than 85% of the world's photovoltaic installed capacity at the end of 2023.

During cloudy periods or in the early morning and late evening when there isn't enough light, monocrystalline panels may generate about 10%-12% more than polycrystalline panels. In continuously rainy months, a farm with a 10 kW monocrystalline system can produce about 600 kWh of electricity, while the polycrystalline system may barely reach 500 kWh.

Most monocrystalline panels have a very low annual performance degradation rate of only 0.3%-0.5% per year over their service life of 25-30 years. A similar module with an initial power output of 350 W can still provide about 315 W of power output after 20 years.

Assuming an electricity cost of $0.15/kWh, an average household could save around $1,050 a year with the help of a 5 kW monocrystalline system, producing approximately 7,000 kWh of electricity per year. In two years, the use of fossil fuels by a small town is reduced by approximately 75% thanks to the installation of a 50 kW monocrystalline solar system.

PERC (Passivated Emitter and Rear Cell) technology effectively reduces electron recombination losses, improving efficiency by about 1%-2%.

Long-Lasting Performance

Most monocrystalline panels have a warranty for 25-30 years, while their actual life span often surpasses 30 years. Most monocrystalline solar panels have an annual degradation rate of only 0.3%-0.5%. If the initial output power of a panel is 400 W, then after 25 years it would still be able to maintain close to 85%-90% of its power output, while the polycrystalline panels may only maintain 80%-85% of their performance.

The electricity that will be generated by a monocrystalline solar system, at 1 MW, installed in the logistics center during its useful life of 25 years is forecasted to be about 37-40 million kWh. Considering the LCOE, or Levelized Cost of Electricity, the price is around $0.05-$0.08/kWh for monocrystalline panels, whereas for polycrystalline panels, the price stands at about $0.06-$0.10/kWh.

Temperature coefficients are generally between -0.3%/°C and -0.4%/°C for monocrystalline panels, indicating that their efficiencies drop by less than 0.4% per 1°C rise in temperature. The temperature coefficient of the polycrystalline panel is around -0.4%/°C to -0.5%/°C.

The mechanical load resistance for monocrystalline panels reaches 5,400 Pa, which corresponds to over 1 meter of snow. Their wind resistance is as high as 2,400 Pa, hence they are able to resist wind of about 60 m/h.

A rural electrification project installed 2,000 monocrystalline solar panels, and after more than 10 years of operation, the overall system performance was still above 90%. These households have saved about $100 in energy costs per year and reduced carbon emissions by over 30 tons.

While the annual failure rate for monocrystalline panels is normally less than 0.5%, for polycrystalline panels, it could be near 1% per year. Over a period of 10 years, just 5 out of 1,000 monocrystalline panels would be in need of repair, but over 10 polycrystalline panels may.

A mining company installed a 5 MW monocrystalline solar system in the desert and, after 6 years of operation, still had an efficiency of more than 93% with savings of over $1 million in diesel power generation.


Space-Saving Design

A standard monocrystalline panel with an area of 1.7 m² has a power output of 370-450 W, while the power output for polycrystalline panels of similar size is normally in the range of 300-350 W. In the same roof area, panels of monocrystalline can produce 20%-30% more electricity. In fact, for a typical residential roof area of about 50 m², a monocrystalline installation can install about 25 panels with a total power output of approximately 10 kW, while for a polycrystalline one, it could only reach about 8 kW.

In the case of a monocrystalline solar system, on a single 5,000 m² factory roof, about 3,000 panels may be deployed, with a total power of 1.2 MW. Using polycrystalline panels allows the deployment of only about 2,500 panels, while the total power developed is only 0.875 MW.

The mounting materials for a 5 kW monocrystalline system cost in the range of $500-$700, while the mounting materials for a polycrystalline system of the same capacity can cost upwards of $800.

The roof area of an RV is usually around 10-12 m². If monocrystalline panels are opted for, then approximately 8-10 panels can be fitted, with a total power output of 3-4 kW, while polycrystalline panels can only provide 2-3 kW of electricity in the same area.

This corresponds to an installation capacity of 50-60 kW in case of using a monocrystalline solar system for a 200-300 m² roof space, while a polycrystalline system could achieve about 40 kW. Similarly, for one hectare, the power achievable from an agricultural site is around 1 MW for a monocrystalline system, while that for a polycrystalline system usually lies around 0.8 MW.

In a Pacific island area where only 2 hectares of space was available for construction, a monocrystalline solar system was installed with a 2.5 MW photovoltaic power generation facility, whereas if polycrystalline systems were chosen, the number would have been reduced to 2 MW.

In Japan or South Korea, the average residential roof area is usually between 20-30 m². This area can allow the installation of 8-10 panels if a monocrystalline solar system is chosen, generating around 3-4 kW of power. A polycrystalline system in the same area may only produce 2-3 kW. Their weight-power unit capacity is often installed between 200-250 W/m²-more significantly compared with the 150-200 W/m² of polycrystalline panels.

Generates More Electricity

Efficiency: Usually, the conversion efficiency of mono panels is in the range of 20%-25%. At standard test conditions, which means light intensity of 1,000 W/m² at 25°C, a 400 W monocrystalline panel produces around 1.6-2 kWh/d, while the same surface covered by polycrystalline panels generates only 1.2-1.5 kWh.

In an area that receives an average annual sunshine duration of 5 hours/day, a monocrystalline solar system with 10 kW can produce about 18,250 kWh of electricity in a year, while a polycrystalline system of the same specification produces only 15,000 kWh. During the whole lifecycle of the system, which is usually 25-30 years, a monocrystalline system can generate about 80,000-100,000 more kWh.

A small factory with a 50 kW solar system increased its monthly output of electricity from 6,000 kWh to 7,500 kWh after switching to monocrystalline panels. In regions of the US and Australia, the buyback price for electricity may reach $0.1-$0.2/kWh.

In the morning, evening, or on cloudy days, the yield of a monocrystalline panel can range from 5%-10% greater than that for polycrystalline ones. At half of the irradiance from the test conditions, power output for the monocrystalline modules could still prevail at about 10%-12%, with polycrystalline modules falling as low as 7%-9%.

Monocrystalline panels for tracking installations are systems that track the angle of the sun and, depending on the nature of the tracking, can generate annually 15%-20% more electricity than polycrystalline panel fixed installations. A 100 kW commercial photovoltaic power station using a monocrystalline panel tracking system can generate about 30,000 kWh more electricity annually and reduce carbon emissions by about 20 tons.

The temperature coefficient of monocrystalline panels is usually within the range of -0.3%/°C to -0.4%/°C. In a region of Saudi Arabia with a temperature as high as 45°C, the actual power generation of monocrystalline systems is about 7% higher than that of polycrystalline systems, and the additional electricity generated is equivalent to the annual electricity consumption of 100 households.

A large ground-mounted photovoltaic station in Gansu, China, uses a 10 MW monocrystalline system, while its annual actual power generation is about 18 million kWh, compared with only 15 million kWh annually generated by an adjacent polycrystalline system.

This would translate to an approximate consumption of 20 kWh/d for a typical household. The 5 kW monocrystalline system generates about 25 kWh of electricity on sunny days, while the remainder of 5 kWh is either stored in the batteries or sold back to the grid. A polycrystalline system would generate approximately 20 kWh.

The solar-powered drone "Solar Impulse" has over 17,000 monocrystalline solar cells on its wings, each with an area of about 0.1 m², with a total power output of 50 kW.

Easy to Install

These panels usually have an average length of 1.7 m by 1 m in size and weigh 18-20 kg. A residential house usually requires installing a 5 kW system, which normally gets all installation work done within 10-12 hours. For the installation of a 10 kW system, 24-26 monocrystalline panels are used, whereas in polycrystalline systems it requires 28-30 panels.

The mounting costs for the monocrystalline system are usually 10%-15% lower than those for the polycrystalline system. In fact, one solar farm that was based on the monocrystalline system used only 75% of the planned land area and was able to save about 25% of the land development costs.

This US community installation team installed an average of 10 systems daily, with each similar-scale polycrystalline project requiring at least an additional 2-3 hours each day for debugging. Preassembly technology can also help the onsite installation of a mono system save about 30%-40%.

Traditional polycrystalline panels weigh approximately 22-25 kg each, but monocrystalline silicon is lighter, typically weighing between 18-20 kg.

In a remote region of Australia, the installation of photovoltaic systems for 50 households took only 3 weeks. While similar-scale polycrystalline projects take over a month, monocrystalline panels, with their installation convenience, reduce about 15% of the total construction cost.

In the case of a project for a 300 MW ground-mounted station in China, the whole station installation cycle was shortened by 20 days and saved over $1 million in labor and renting equipment costs.

It takes about 8-10 hours to install a 3 kW DIY mono-crystalline system and costs around 25% less than installing it by a professional. The polycrystalline kits take more than 12 hours since there are a greater number of wiring and panels.

Reliable Warranty

Most monocrystalline solar panel manufacturers offer a product warranty for 10-12 years and a performance warranty for 25-30 years. Within the 25-year service life, the output power of the panel can maintain a range between 80%-90% of the initial power. A 400 W monocrystalline panel can still output at least 320-360 W of power after 25 years.

One of the known solar brands says its monocrystalline panels have an annual degradation rate of no more than 0.3%, with the average within the industry being 0.5% per year. After 25 years, its panels will generate a power output 5%-6% higher than the industry average. For a 50 kW solar system, this is the difference between an additional 7,500-9,000 kWh of electricity generation.

Monocrystalline panels have withstood pressure from over 1 m of snow in a Nordic solar station and temperatures as low as -30°C. After more than 10 years, the failure rate was only 0.2% for the monocrystalline system, while that for the polycrystalline system was close to 1%. This reduced failure rate saved approximately 15% in maintenance costs.

In a similar study, a 100 MW photovoltaic station in western China showed that the average output power of the monocrystalline system still maintained around 88% of its initial power. The result was far higher than the 80% that was promised during the warranty.

The customer satisfaction rate on the warranty for monocrystalline panels is very high, 96%, compared to 85% for polycrystalline. Generally, these panels are usually repaired or replaced within 48 hours. Due to a disaster in a windstorm, in just 2 weeks, the replacement of damaged panels worth more than $100,000 was completed free by a German Company.

Popular for All Projects

Over 85% of newly installed photovoltaic capacities are using monocrystalline panels in 2023. A monocrystalline system of 5 kW can be installed for an average household that consumes 20 kWh of electricity per day, which requires only 30 m² of roof space. It generates 6,000-7,500 kWh of electricity every year, while a polycrystalline system requires 40 m² or more to produce the same amount of electricity. These families will save an average of $1,000-$1,200 annually in electricity bills after the installation of the monocrystalline systems.

A large supermarket in California installed a 500 kW monocrystalline rooftop solar system to cater to about 60% of the daily electricity demand of the supermarket. The first year of operations from this system yielded more than $80,000 in savings on electricity and a reduction of carbon emissions by 120 tons.

A 200 MW solar station in Gansu, China, used a fully monocrystalline system and attained an annual generation of 380 million kWh. Such high-capacity generation saves the local government about $5 million in energy costs every year, with carbon emissions reduced by 500,000 tons. A station of the same size but made from polycrystalline generated only 330 million kWh under similar conditions.

A village in India installed a 100 kW monocrystalline solar microgrid system that generated about 400 kWh of stable electricity every day to support the daily electricity needs of 50 households and 3 small businesses.

A standard-sized RV could fit a 2-3 kW monocrystalline solar system on its roof; this would provide about 8-12 kWh of electricity a day, while polycrystalline panels of the same area generally produce up to 20%-30% less power.

In this case, a common agricultural photovoltaic glasshouse with a monocrystalline solar system could install 1.5 MW and generate 2.2 million kWh of electricity per year. However, in the same area, polycrystalline systems usually have only a power capacity of 1.2 MW.

An Australian city has a solar-powered bus station powered by a 5 kW monocrystalline solar system that provides about 20 kWh of clean electricity per day, while the monocrystalline system generates about 10% more power during weak light periods than polycrystalline systems.

A large data center installed a 100 MW monocrystalline solar system, generating about 1.5 billion kWh of green electricity each year, accounting for 40% of the total consumption of its electric quantity. In addition, the monocrystalline panels save more than $100 million in electricity costs within 5 years.