If you ask a farmer about the biggest vegetable they have ever grown, they will excitedly tell you about the 2.5 kg potato that looked like a teddy bear. But ask a solar expert about the largest panel they have seen or used, and they will just shrug. The reason for this is not that gigantic solar panels can’t be made - it is simply because somewhat standardization of solar panel sizing helps with the logistics and installation.
But how big are solar panels exactly? Let us find out.
What is a Typical Solar Panel’s Size?
A typical home solar panel today is about 1.1 metres wide and 1.7 m to 2 m long, while the thickness is usually 3 cm. These dimensions vary a little between manufacturers, but most panels sold in New Zealand now share the same 1134 mm width.
You may have noticed that the length varies quite a bit (1.7-2 m), compared to the width and thickness. That comes down to how many cells are packed in. Older panels came in two standard sizes - 60-cell (around 1.6 m long) and 72-cell (around 2 m long) - made from cells about 15 cm x 15 cm. Today’s panels use bigger cells, about 18 cm square, cut in half. A common home panel has 108 half-cells (6 rows of 18), which is where the “54” in model names like LONGi’s LR7-54 or JA Solar’s JAM54 comes from. Longer panels like the Jinko Tiger Neo 475 W stretch to 1.9 m or more.
What is a Typical Solar Panel’s Weight?
A typical home solar panel today will weigh around 21 to 25 kg. The lightest in our table below, the AIKO Neostar 3S54, is 20.6 kg, while big commercial-size panels can top 30 kg. That works out to roughly 10 to 12 kg per square metre of roof, before you add the mounting rails.
Interestingly, the solar cells in a panel are the lightest component of the panel, and make less than 5% of the solar module’s weight. The majority of a solar panel’s weight comes from the front glass - a large, rectangular piece of glass with anti-reflective layer. Then comes the aluminium frame and back sheet.
Solar Panel Sizes and Wattages
When two people from the solar industry are speaking to each other and they use the word “big” to describe a solar panel, they are likely referring to its power rating, and not its physical size. To understand if a solar panel is any good, knowing its physical size is hardly useful. What matters more is its power rating, given in watts.
While it is true that the physical size and watts will be proportional to each other, high-efficiency panels can generate more power per unit surface area. For example, the AIKO Neostar 3S54 and the Canadian Solar TOPHiKu6 are exactly the same size (1762 x 1134 mm), but the AIKO is rated at 495 W and the Canadian Solar at 455 W. In other words, “efficiency”, a.k.a. power produced per unit area matters more than the physical dimensions of a solar panel.
Does a Solar Panel’s Size Matter?
We just discussed that the efficiency of a solar module matters more than just its dimensions. But if we put the efficiency aspect aside for a while, how does the physical size impact the solar panel’s use?
Theoretically, it is possible to manufacture a solar panel of any size. You can build a single panel that is the size of your roof, and then have just one panel generating all your power. It might be a “cool” idea, but it is not a smart one. If a panel is too long, it becomes difficult for the panel to support its own weight, and it is susceptible to bending and breaking near the centre. Excessively large solar panels can also be difficult to manufacture, transport and install.
Overall, the industry has settled on panels around 1.1 m wide and 1.7 to 2 m long for homes - big enough to pack in 450 to 500 W, but still manageable to handle and install. Bigger panels of 2.2 m or more, like the 585 W Suntech in our table below, are mostly used on commercial roofs and solar farms.
Sizes and Weights of Solar Panels in New Zealand
Solar power companies in New Zealand offer a variety of solar panels. And though there are a dozen sizes available, most panels going on Kiwi roofs now range from about 420 to 515 W. Here is a table of sizes and weights for some of the panels on our choosing solar panels list.
| Model | Power Rating | Dimensions | Weight |
| AIKO Neostar 3S54 | 495 W | 1762 x 1134 x 30 mm | 20.6 kg |
| LONGi Hi-MO X10 Explorer | 475 W | 1800 x 1134 x 30 mm | 21.6 kg |
| REC Alpha Pure-RX | 470 W | 1728 x 1205 x 30 mm | 22.7 kg |
| Phono Solar Quasar | 475 W | 1800 x 1134 x 30 mm | 23.5 kg |
| Trina Solar Vertex S+ | 515 W | 1961 x 1134 x 30 mm | 23.5 kg |
| Jinko Tiger Neo All Black | 475 W | 1903 x 1134 x 30 mm | 24.2 kg |
| Canadian Solar TOPHiKu6 All Black | 455 W | 1762 x 1134 x 30 mm | 24.6 kg |
| Suntech Ultra V Pro Bifacial | 585 W | 2278 x 1134 x 30 mm | 32 kg |
Solar Panel System Dimensions
Once we have answered the question of what the size and weight of a solar panel is, the next logical question is “how big is a typical solar system?” Usually, a 5 to 10 kW system fits the needs of most Kiwis, and new home systems now average about 8 kW (Electricity Authority data). While an 8 kW system will offset a big chunk of your power consumption, a smaller 3 to 5 kW system might also make a good option to reduce your monthly bills.
Considering 450 W panels, you will need about 18 panels to generate about 8 kW of power, or about 7 panels to generate 3 kW. Considering the typical dimensions of 1.8 x 1.13 m for a 450 W panel (about 2 m2 each), an 8 kW system may take up a roof area of 2 x 18 = 36 m2, and a 3 kW system about 14 m2. However, considering spaces between panels and some margins for wiring, racking etc., installers generally use the rule of thumb of about 5 to 6 m2 of roof per kW of solar installed.
Solar Panel Sizes and Efficiency
You may have seen the historic image from the 1950’s where four people are loading a 1 megabyte IBM hard drive into a truck, placed against the image of a modern 1 terabyte SD card the size of a thumbnail.
Although not that dramatically, solar panels have also consistently become more and more efficient. Just a decade ago, a panel efficiency of 18% was considered excellent. Today, most panels sold in New Zealand sit between 21% and 24%, and the best home panels, like the AIKO Neostar 3S54 at 24.8%, are knocking on the door of the holy 25% mark.
Consequently, this means solar panels pack more power-generating ability in the same space. This means either the panels can get smaller, or remain the same physical size and offer more power. As it seems logical, manufacturers went with the latter option. A decade ago, a 250 W panel was considered “large”, but today, 450 to 500 W panels are the norm on Kiwi roofs.
We don’t know how solar panels will look in the future. But we know one thing for sure - solar panels have never been more powerful and more efficient, and this is definitely the best time to go solar!