The 100-watt solar panel. It’s conveniently sized, easy to replace, and best of all, portable. This has led to their growing popularity, especially for camping, RVing, and other activities.
But before we go further, it’s important to point out that a 100-watt panel is smaller than the typical residential solar panel. While they can still be an effective way to produce solar energy, you’ll only be able to power smaller devices with the solar energy you collect.
Solar panels of this size are often paired with some form of battery storage. This allows you to store excess energy, and use it when needed.
Here is a more in-depth look into what a 100-watt panel is, and what its best uses are.
How big is a 100-watt solar panel and how much does it cost?
100-watt panels vary in size based on their efficiency and design, but typically measure around 47 x 21.3 x 1.4 inches.
When it comes to purchasing one, you can either buy just the 100-watt solar module, or you can get the full 100-watt solar panel kit that includes the module, a charge controller, cables, and brackets.
Depending on the brand, its efficiency, and the equipment that’s included, prices can vary quite a bit. Generally speaking, you can find a standalone 100-watt panel for as little $100 or less, while a complete 100 W starter kit can cost as much as $300 plus.
The effectiveness of the panel relies on many factors, including quality, manufacturer, materials, and more.
See how much a solar panel system would cost for your home
How much energy does a 100-watt solar panel produce?
A 100-watt panel refers to a solar photovoltaic module that is rated 100 watts. This means that it has a power output of up to 100 watts of DC output under optimal conditions.
Lots of things need to line up for you to achieve the maximum possible output: the panel must be properly installed at the right angle and direction, and crucially, must be receiving peak sun (like what you receive at noon).
Of course, you won’t actually get optimal conditions most of the time. To begin with, your panel will receive less-than-peak sunshine for a large part of the day, such as in the morning and late afternoon. At those times, your panel will produce far less than 100 W. Further complicating issues is the fact that the total amount of sunlight varies by location, because of geography and climate. For example, sunny Nevada gets a lot more sun than snowy Vermont!
What this all means is that a 100-watt solar panel will produce different amounts of total power (measured in watt-hours or kilowatt-hours) – depending on where you use it.
Luckily, we can access data for the average amount of sunlight received in each state in the U.S. We can use that to calculate the average amount of power a 100-watt solar panel will produce per day in each state.
We’ve compiled the results in a graphic below if you want to see how much a 100-watt panel will produce where you live.
Average watt hours (Wh) produced by a 100-watt panel per day in each state
This map shows watt hours per 100 watts of solar panel system capacity. It also assumes a perfect installation facing due south, at an optimal tilt angle, and unshaded between 9am and 3pm.
Note that these figures show average output. You can expect your panel to produce roughly this amount per day in the spring and fall. In summer, because the days are longer, you’ll see higher output – and in the winter you can expect less.
Should you pair a 100-watt solar panel with a battery?
Yes, that is usually a good idea. Remember, your solar panels produce varying amounts of electricity during the day — and none at night.
With home solar systems, this isn’t an issue, as you can import and export electricity from the grid as needed. But with a 100 W solar panel, any unused power you produce will go to waste, and you’ll be left with no power available to use when the sun has gone down.
If you’re thinking of getting a lead acid battery, keep in mind that these shouldn’t be run below 50% capacity. That means you should get a solar battery that can store at least twice the daily output of your panels. Assuming an average daily solar production of 300 Wh, you would need a battery that can store 600 Wh.
Newer lithium-ion (li-ion) batteries are different: they can be discharged almost completely. In that case, get battery with storage that’s just a bit higher than your solar panel’s daily output.
What will a 100-watt solar panel run?
Daily, a single 100-watt solar panel can power a few small devices reliably — provided you factor in a few things. What sort of charge controller you use will be a consideration, as will your battery.
Your limitations will be the capacity of the battery you use, and the energy needs of devices — you may need to run one at a time, or at intervals.
That said, with a single 100-watt panel connected to the proper deep cycle battery, you can expect to run the following devices throughout the day:
- Laptops – 60 Wh
- Ceiling fan – 35 Wh
- Certain lamps and lighting – 14 Wh (for CFLs)
- LEDs – 10 Wh
- WiFi Router – 6 Wh
- Smartphone charging – 5 Wh
If you’re curious about an appliance that’s not listed above, check out Energy.gov’s Appliance Energy Calculator to find consumption figures. Keep in mind that both their figures, and the ones provided above are average figures for those appliances; you’ll have to check your own device to check its actual power consumption.
Air conditioners, microwaves, and portable heaters won’t run from a single 100-watt solar panel; for these you’ll need many more panels.
Can you connect multiple 100-watt panels together?
Yes, you have the option of networking solar panels together to increase the total output. For instance, if you connect two together – in either series or parallel – you’ll get as much as 200 watts. Connect three and you’ll get 300 watts, and so on and so forth.
Adding an additional panel to an existing setup is a common solution, and can be achieved relatively easily.
Two 100-watt panels networked together. Image source: CheapRVLiving
Can you power a home with 100-watt solar panels?
You could if you wanted to, but it wouldn’t make financial sense.
Homes use a lot of energy, and they generally require a solar system sized between 5 kW and 10 kW (that’s 5,000–10,000 watts). To build a system that size using 100-watt solar panels would require networking 50 to 100 of them together.
But there are many reasons why you wouldn’t want to do this. Installing so many separate panels means a more complicated installation due to all the extra framing, racking, and fasteners. Furthermore, more panels means more electrical connections, and hence a less reliable system.
Most crucially, 100-watt solar panels provide you less bang for buck, i.e. you get less watt per dollar when compared to larger panels.
All of these factors mean that a home solar system built with 100-watt solar panels simply isn’t worth it. For this reason, most residential solar systems use larger solar panels, usually rated between 250 W and 400 W.
What companies make 100-watt solar panels?
There are several manufacturers that specialize in small and portable solar panels that are rated 100 watts or a similar size. Out of these, the most famous manufacturer is Renogy, which tops most ‘best-of’ lists for portable solar panels, including Amazon’s.
Other notable sellers of 100-watt solar panels include:
Interestingly, most top-rated solar panel manufacturers, including the ones making the most efficient solar panels, don’t produce 100-watt solar panels. This is generally because they are more focused on larger solar panels that are suitable for home installations or solar farms.
100-watt panels summary: They’re convenient and easy to use, but offer limited power
If you’re looking for a rooftop solar installation, 100-watt solar panels are too small to be cost-effective.
100-watt panels are great because of their portability, which makes them an excellent choice for powering a few small appliances for your RV or while camping.
Another ideal use for them is as an introduction to solar. If you want to get some hands-on experience in generating your own power from the sun, a 100-watt solar panel kit is a great way to dip your toes in the water.