500-Watt Solar Panels: What to Know

What is a 500-watt solar panel?

Wattage refers to a solar panel’s ability to produce power, and most solar panels sold to consumers range from 200 to 400 watts. That means a 500-watt solar panel can help deliver very high energy yields for your home or business.

While some 500-watt solar panels utilize the same technology seen in today’s lower-wattage products, PV manufacturers are incorporating a few interesting technologies to maximize power generation:

• Half-cut solar cells can double a solar panel’s capacity without increasing its size. By literally cutting the size of PV cells in half, 500-watt solar panels may be made up of as many as 144 individual sections, which is twice as many as a traditional 72-cell panel.
• Bifacial solar panels can absorb light on both their top and bottom sides, squeezing even more energy out of each day’s direct sun hours. The extra electricity generated through the bottom of the panel helps bifacial solar panels boost their potential power capacity.

Bifacial solar panels can only work properly when there is sufficient open space for light to refract below them. This makes bifacial generation much more suitable for ground-mounted installations than roof installations.

How big is a 500-watt solar panel?

The exact size of a given 500-watt solar panel depends on its manufacturer’s specifications. With that said, here are a few size specifications for some solar panels available at the time of publishing that are in the 500-watt range.

Installation requirements and considerations for 500-watt solar panels

If you’re thinking about installing an array of 500-watt solar panels, you’ll have to ensure your space is equipped to handle them.

Space and mounting needs

The average dimensions of a solar panel are 65 inches by 39 inches. That means the average solar panel takes up just 18 square feet of space. In contrast, the 500-watt solar panels in the table above each take up substantially more space.

If you plan to install 500-watt panels, make sure you have the surface area for them. Remember that you may not be able to buy the panel you want as a single panel, but rather as a pack of multiple panels.

If you plan to mount your panels on the roof, weight is another factor to consider. Five hundred-watt panels are generally heavier than smaller panels, so it may be a good idea to have a professional inspect your roof and determine whether it could handle panels of this size. If you have the land, an array of 500-watt panels might be better as a ground installation.

Permitting and code compliance

Before installing your solar array, be sure that it would be compliant with your municipal and neighborhood regulations.

While local laws vary, your contractor may need to secure a permit before installing solar panels on your home. And if you plan to connect your panels to your local electric grid, someone from your local government may inspect your installation to ensure compliance with local laws before it’s connected.

» MORE: Solar panel size and weight: a guide

What can 500-watt solar panels run?

You can run almost anything with 500-watt solar panels if you have enough solar capacity and enough sunlight. The benefit of more efficient solar panels is that they generally let you do more with less.

A small array of 500-watt panels can easily supply enough power to run a residence or business, and because ground-mounted arrays can work well in open fields, large installations of 500-watt bifacial solar panels are well suited to running entire communities. Just be aware that you should connect your solar energy system to the electrical grid or a battery backup system if you want to take full advantage of the energy it produces.

However, 500-watt panels aren’t necessarily the best choice for every situation. For example, monofacial 500-watt solar panels may be too big for rooftop installations or small, do-it-yourself systems, even though they can lay flat on a surface as other solar panels do.

What can one 500-watt solar panel run?

Five hundred watts of solar potential exposed to daily sunlight can provide an ongoing supply of sustainable, renewable electricity to run lights, fans, TVs, phone chargers and practically any household electronic device. That means one 500-watt solar panel (or an array of the same total capacity) can run almost any single appliance for a full day as long as it’s equipped with battery storage.

Unfortunately, buying a single 500-watt panel may be easier said than done — some manufacturers have minimum order requirements of eight panels or more.

On the other hand, many brands package smaller solar panels together to create a “500-watt solar panel kit.” These kits can consist of any number of same-wattage panels, such as two 250-watt panels or a set of five 100-watt panels.

How many 500-watt solar panels do you need for a larger installation?

It can be difficult to determine how many solar panels you need for a unique installation, but for most homeowners, it comes down to a matter of your goals and your available space.

Given that 500-watt solar panels can take up around 28 square feet each, you’d need roughly 450 square feet of unobstructed roof space for the 16 panels it takes to offset the energy use of the average U.S. home. That’s significantly less space than the 720 square feet it would take to get an equal amount of capacity from 40 200-watt solar panels.

However, currently available 500-watt panels may have passed the point of diminishing returns on this front. An 8-kilowatt solar array made with 400-watt panels would actually need less space (about 420 square feet). That’s because 400-watt panels are significantly smaller than 500-watt panels, at about 21 square feet each.

» LEARN: What is community solar?

How much energy can a 500-watt solar panel produce?

On average, a single 500-watt solar panel can generate about 2 kilowatt-hours of electricity every day. However, the amount of energy a 500-watt solar panel can actually produce in real-world conditions depends on several different factors, including the daily sunlight, the solar panel’s efficiency and the other equipment used to process and store that energy.

Let’s take a closer look at how you can estimate the impact of these factors on your PV system.

Solar panels can work at very low efficiencies when exposed to indirect sunlight, but their most significant power generation happens within a daily window known as “peak sun hours.” Your expected number of peak sunlight hours each day depends on the weather, the season and your location.

500 watts is half a kilowatt.

While states including New Mexico, Arizona and Nevada average over six hours of daily sun, Pennsylvania, New York and Illinois average fewer than four.

Using a tool such as the Global Solar Atlas, you can find the estimated solar power potential of your address. This potential is often expressed in kilowatt-hours of potential per kilowatt of capacity installed. To calculate how much energy a single 500-watt panel can produce at your location, simply divide the number of potential kilowatt-hours per kilowatt of capacity in half.

For example, let’s say you wanted to install a 500-watt solar panel on the White House. According to the Global Solar Atlas, 1 kilowatt of solar capacity installed there would generate an average of 4.028 kilowatt-hours of electricity per day. That means a 500-watt panel there would generate 2.014 kilowatt-hours per day.

» LEARN: How do solar panels work?

Are 500-watt solar panels right for you?

While 500-watt solar panels are among the most powerful, efficient options on the market today, they’re not right for every solar installation.

Due to their large footprint and installation requirements, 500-watt solar panels may be an unnecessary investment for residential users and DIY hobbyists. On the other hand, if you need a lot of solar power and you have the space for them, 500-watt panels are at least worth considering, especially as technology advances over time and new products enter the market.

» MORE: Best solar panels

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