Which types of solar panels are best in terms of efficiency?
Monocrystalline solar panels are the best all-round choice for efficiency, cost and length of working life. Polycrystalline panels are less efficient but also less expensive, so good for DIY solar panel projects on a budget. Monocrystalline panels have an efficiency of about 22%, while polycrystalline efficiency is around 18%.
4 types of solar panels to choose from
Solar panel technology has improved significantly in the past few years. A good approach to the subject is to review some basic types of solar panels:
Monocrystalline
Polycrystalline
Thin Film (very flexible)
Flexible
Video – Which is better solar panel mono or poly?
Types of solar panels for houses
What are the 3 types of solar panels recommended?
Is there a difference in the quality of solar panels?
It Depends On Your Needs. Although solar panels are evolving to the requirements of a world needing more and more energy, at present they are not that efficient, depending on the brand, type and quality you buy.
There is hope on the horizon, however – NASA use solar panels in space that are up to 34% efficient. That’s to say, 34% of the sun’s energy gets converted into usable electricity.
Many scientific organisations are making innovative gains in solar technology, such as Harvard University.
All commercial solar panels have an efficiency of between 13 to 20%, depending on the type and quality of construction.
In this post I’ll discuss the various types and why they might be a good fit for your project.
Let’s dive in.
Are monocrystalline solar panels the best?
Monocrystalline gives the best solar cell efficiency
What is monocrystalline solar panel? Construction
Monocrystalline solar panels are easily recognized by the individual cell shape. Each cell is a square with the corners cut off.
If you look a little closer, you’ll see that the corners are slightly curved. This is because each cell is a thin slice that was cut off a single crystal grown in the shape of a round ingot in a lab – hence ‘mono’, meaning one crystal.
The bigger rounded edges are then sliced off, leaving a very thin shape as you see below:
A Monocrystalline Solar Cell Showing The Characteristic Cut Corners
The quality of the best solar cells give higher efficiency
Each side of the crystals are coated with a thin layer of silicon to form the photovoltaic cell needed to convert sunlight into electrical energy. Tiny metallic bus-bars then criss-cross the surface to collect the voltage and current generated.
Video Explaining How Monocrystalline Solar Panels Are Made
How long do Monocrystalline solar panels last?
Monocrystalline solar panels are more expensive than poly, but they have a higher efficiency of approaching 20% compared to 15% or so for polycrystalline panels.
With a long working life of up to 30 years, it’s well-worth spending the extra money for a permanent installation.
It’s a mistake to choose a solar panel based on initial cost, as different panels might be better for different needs and environments.
As a general rule, for land-based installations, polycrystalline give the best of all worlds.
Monocrystalline Panels Common Sizes
The most common sizes of solar panel are 60 and 72 cells. However, 96 cell panels are made.
Panels can be anything between 25 to 2000 mm long and 20 to 1000 mm wide. Of course the power output varies upwards as the surface area gets bigger.
Most solar panels for domestic use are around 150 to 160 watts and may have an area of 1000 x 990 mm. Such panels weigh 12 to 15 kgs each. Bigger panels are being produced and 250 or even 350 watts is not uncommon.
Image – A Monocrystalline Solar Panel Roof Installation – Best For Overall Cost, Life and Efficiency.
The best polycrystalline solar panels have slightly lower effieicny than monocrystalline
Characteristics
Monocrystalline
Polycrystalline
Thin Film (amorphous)
Composition
One crystal
Multiple crystals
Thin silicon layers
Color
Black
Blue
Multiple - varies
Efficiency
17 to 23%
10 to 14%
5 to 6%
Lifetime Duration
25 to 30 years
20 to 25 years
15 to 20 years
Manufacturing Process
Complicated
Easier
Complicated
Cost
Expensive
Cheaper
Expensive
Temperature Tolerance
0 to 5%
-15 to +5%
-3 to +3%
Polycrystalline Solar Panels
Although made of the same basic material, polycrystalline cells are made in a slightly different way.
Crystals are grown in one mass, instead of a crystal ingot being grown into a long rod. When the mass of crystals solidify, this is then cut up into wafers and process in a similar way to monocrystalline panels.
Types of solar cells and their efficiency – Polycrystalline Construction
The surface structure looks different, as though it layers, because the crystals overlap each other.
Some people don’t like this look for their home installations – it seems too shiny. Crystal overlap also reduces the efficiency with which they convert sunshine into electricity, so they are not as efficient as monocrystalline.
A Polycrystalline Solar Cell Showing The Dark Marbled Surface Markings
The best panels for most installations are polycrystalline
Polycrystalline Solar Panel Efficiency
Polycrystalline panels have an efficiency of about 15% compared to 20% for monocrystalline.
In that respect we could say that monocrystalline are the ‘best’, but if budget is a constraint and there is plenty of surface area, polycrystal types are still worthwhile.
In fact, the difference in efficiency is reducing all the time as manufacturing methods improve. In general, sizes of mono and polycrystalline panels are about the same.
Thin Film Solar Panels
Image below – Amorphous silicon thin film solar panels are ideal for marine applications
The best monocrystalline solar panels are much more efficient than thin-film panels
Thin film, also called amorphous silicon, solar panels are made in the similar way that newspapers are printed.
Semi-conductor material is sprayed on both sides of an aluminium film to form anode and cathode of a huge solar cell.
The film is then cut up into smaller sections, the power rating depending upon the panel area. These panels are very flexible and can be rolled or folding upon themselves. This is a great advantage for outdoor campers and marine enthusiasts, for example.
Panels can be contoured around the hull of a kayak or the roof of a car and glued into place. This can bring problems with heat in full sunshine, but the advantages are obvious.
The only downside is the efficiency, which is much lower than mono or polycrystalline cells, at 7 to 13%. This is improving all the time, so keep an eye out for the future!
Flexible Solar Panels
Flexible Monocrystalline Panels Are Very Useful In Marine Applications
Flexible-type are the best DIY solar panels for RV mounting
They are strictly-speaking monocrystalline in design, which means the cells are cut in thin slices from a continuously drawn ingot of semi-conductor material, but the slices are reduced in thickness even further.
These very thinner solar cell slices are sandwiched between layers of plastic until they are very well protected against the elements.
Such panels can be bent through 30 degrees or so, and so great for outdoor projects where a normal panel might get damaged.
Efficiency is lower than rigid solar panels at 13%, so this is a downside which needs to be considered when using in marine applications. For example, if motorizing a kayak the available space for solar panel mounting is small.
The biggest advantage for mobile or marine use is their weight. A rigid solar panel weighs between 10 to 12 kg, while a similar powered flexible panel might weigh 2 or 3 kg, depending on the manufacturer.
Some years ago there was quite a marked difference between mono and poly cell efficiency, but this gap is closing all the time. Most goo installers will give you a choice.
While it’s true that monocrystalline panels are more efficient, they are also more expensive. If you have plenty of space it may be more cost effective to simply install polycrystalline and add a couple more panels to maintain your power output.
The table below gives some basic specifications for 10 top solar panels on the market. Prices are not shown beacuse these tend to be dynamic. They also vary according to quality, so it’s best to compare.
Renogy are fast making a name for innovation with quality and I recommend Renogy products. (Checkout the latest prices’) I’ve found by experience that cutting cost when buying solar products is a big mistake in the long term.
Types of solar panels for houses – the most efficient solar panel type
The most powerful solar panel available is the SunPower 415 at 415 watts, which is a monocrystalline cell panel. Mono is the most efficient but polycrystalline type panels are catching up all the time.
They are less expensive and if your home has plenty of roof space, a couple more panels will soon make up the shortfall between mono and poly type solar modules.
Which solar inverter is best?
An inverter is an electronic device which converts the direct current generated by a solar panel into alternating current used in domestic premises. It is essential if mains appliances are to be powered by solar.
An inverter should be sized the same as the solar system power rating. This is because inverters are most efficient when fully loaded.
Modern solar system topology mostly features several string inverters, while the most efficient way is to connect a micro-inverter to each panel, or small group of panels.
Why do solar panels face South?
The amount of electricity generated by a solar panel is directly proportional to the intensity of the sun’s energy falling upon it’s surface.
This is called irradiance. In the Western hemisphere, the sun shines predominantly from the South.
Which type of solar panel is best for home use?
In terms of efficiency, monocrystalline solar panels are best, particularly if you have limited space for mounting.
Polycrystalline have a lower power output per panel but are cheaper. If you have plenty of mounting space, it may be a better option. Both types last for up to 30 years.
It all depends on your particular installation and your pocket. Mono solar panels are better in terms of power output efficiency, so you would need less panels for your installation.
However, you could get the same overall power output with just a few more poly solar panels (if you have the space) and it may be cheaper. All installations are different and your solar installer will calculate your needs.
Other resources relating to Solar Panels Types:
Types of Solar Panels: Polycrystalline vs. Monocrystalline
Types of Solar Panels: What You Need to Know | EnergySage
Types of Solar Panels: Which One Is the Best Choice?
Comprehensive Guide to Solar Panel Types
RENOGY are fast becoming the preferred source for solar panels, kits, batteries and solar control accessories. Based in the US, where the products are manufactured, they are widely known and respected for innovation and quality.
