If you are looking into purchasing solar panels and want to know more about the equipment you are buying, you came to the right spot.

by Kasey Harwell, Owner, RayWell Solar

Size and Weight

solar panels

LG panel physical characteristics

Most solar panels have average dimensions of 3.5′ by 5.5′, making a total square footage of 18.25. If you are standing next to one, It would be taller than the average American woman (5′ 4″) and shorter than the average American male (5′ 10″). However they are much thinner than us 🙂  only 1.5″ thick. And a panel’s weight: about 40lbs.


solar panel dimensions

Solar panels dimensions: 5.5′ x 3.5′ x 1.5″




So will a solar panel hurt your roof? Think about this: a roofer climbs onto the roof to install for the first time or later repair it. The ~200 pound roofer is standing on one or two square feet.  In contrast, a solar panel’s 40lb weight is distributed on two rails attached every 4 feet. So the dead load is very small and will not impact the weight of the roof at all. Where you need to be careful is with a snow load. But don’t worry, solar requires structural and electrical permitting that takes into dead, live and wind loads so it matches the local jurisdictions’ requirements for building code. Following the proper permit process keeps you, the consumer, protected.

Solar Cells

solar panel cells

Detailed view of 4 cells and their electrodes creating a circuit

The above example assumes that the solar panel has 60 individual cells that are combined into one module. There are also 72 cell panels that are used often in commercial applications. Each cell is manufactured out of silicon. Wires are connected across the top that allow electrons to move through the circuit. A cell is about 4″ square with the corners cut off.

Some panels come with a white backsheet and others come with a black backsheet. Your HOA might require the all black modules for aesthetics. However to get the largest efficiency, a white backsheet provides more sunlight into the cell.


Most people want the latest and greatest in technology when making a purchase. I know when I buy the latest iPhone, I want the best user experience, memory and speed. Plus when they come out with a new software update, it out dates the hardware of the phone and slows it down. Solar is a little different.

Cell efficiency is getting better all the time, but the new models are more expensive. LG, our favorite panel manufacturer, just released 360W modules after their 335W panel a couple months later. In solar, we price things per watt (not per panel) so that it is easy to compare different products. The higher wattage panel from LG is is much more expensive than the lower wattage panel. You get 7% more power per module from the upgrade, but pay 125% more. When building an array of panels, you can have the same size (say 10kW) with two different efficiency modules and pay very different prices. The advantage of the high efficiency modules is they would use less space since you are getting more power from each panel and you would therefore need fewer panels.


One of the most important pieces of the puzzle when going solar is taking a look at the warranties of the equipment. Solar panels typically have a 10-25 year warranty. Of course, any company can put a lifetime warranty on something and then go out of business. So with solar panels, you want to stay away from companies that might not be here to fulfill their warranty should something go wrong. As your installer if their panels are Tier 1. This means the company is vetted and placed into the top group of trusted solar panel manufacturers.

The end result looks something like this:

solar panel install charleston

RayWell roof mount with LG 310W modules on an overcast day in Charleston, SC

If you haven’t been up and close with a solar panel, hopefully you have a better understanding and can ask questions of your installer. If you have specific questions, feel free to reach out over email: info@raywellsolar.com.


Take a look at LG solar panel lineup: lg.com/us/business/solar-panel/products.