1. Homeowners
  2. Going Solar
  3. Best Solar Companies
  4. 100-watt solar panels: what to know

100-watt solar panels: what to know

How they work and when to use them

Author pictureAuthor picture
Author picture
Written by
Author picture
Edited by
couple holding a laptop and a solar panel

100-watt solar panels are affordable, easy to set up and able to produce electricity anywhere the sun shines. Does this mean they're always the best choice when designing your solar energy project? Not necessarily. In fact, there are plenty of cases where higher-wattage solar panels may be more suitable.

Keep reading to learn the basics of 100-watt solar panels so you can decide whether they’re right for your renewable energy system.

Key insights

  • 100-watt solar panels aren’t ideal for running your home on solar power.
  • However, you can use one or more 100-watt solar panel(s) to power phones, appliances and other small-scale electronics.
  • If you’re planning to string multiple 100-watt solar panels together, be aware of how much space they’ll occupy and make sure you have room to accommodate them.

What will 100-watt solar panels run?

In theory, you can use 100-watt solar panels to run anything powered by electricity. That includes your cell phone, your air conditioner and even your electric vehicle.

However, it takes much more than just one 100-watt solar panel to make that happen. Compared with the 300-watt and 400-watt solar panels more commonly used on homes and commercial buildings, 100-watt solar panels make much more sense for smaller, low-power, budget-conscious installations.

Some of the most popular uses for 100-watt solar panels include powering single appliances, security systems, automatic gates and water pumps.

A ConsumerAffairs reviewer from North Carolina purchased two lithium batteries and “four 100-watt solar panels” to run a refrigerator on clean, off-grid energy: “When it's warmer, it takes more to keep the refrigerator cool so it lasts between 15 to 17 hours. But in the winter, it didn't seem to drain it as quickly. If we use it to charge phones or plug in some lights, the battery can last 24 hours.”

What will one 100-watt solar panel run?

One 100-watt solar panel can be used to run a variety of small electronics, such as lights, phones, laptops, fans, TVs or kitchen appliances, but not all at once.

We’ll jump into some more precise calculations later, but in general, you can count on one 100-watt solar panel to generate enough electricity to run one or two small electronics each day. Knowing this, many people choose to wire together multiple 100-watt panels to generate extra solar power.

How many 100-watt solar panels do you need for a larger installation?

For the most part, you can “work backward” from your project’s approximate annual electricity consumption to determine the number of solar panels you need. (Just remember that every solar energy system is different, so you may want to consider some of the unique variables that pertain to your project if you want a more exact figure.)

Number of 100-watt solar panelsSystem size (in kW)Average annual kWh producedExample use
1 0.1 kW 155 kWh Lights, phone chargers and other small devices
4 0.4 kW 620 kWh RV, camper van or boat
10 1 kW 1,550 kWh Small, off-grid cabin
68 6.8 kW 10,540 kWh Average American home

The last row of the above table shows why attempting to run a large-scale solar application with 100-watt panels is a bad idea. Although 100-watt panels may be physically smaller than higher-powered options, most homes simply do not have the space to accommodate 68 solar panels on the roof or in the yard. Having 68 solar panels also means 68 different modules that need to be wired, mounted and exposed to full daily sunlight.

Because of this, over the years, 100-watt solar panel options have become more and more specialized for do-it-yourself and small-scale use.

» MORE: Solar panel size and weight: a guide

How much energy can a 100-watt solar panel produce?

Solar panels work by harnessing sunlight and converting it into electricity. This means the amount of energy a 100-watt solar panel can produce depends on several factors, including the time of day, weather, location and season.

Although marginal amounts of energy can be produced in the morning and evening, solar panels work most efficiently during “peak sunlight hours,” a period from midmorning to midafternoon when the sun is at its highest.

1 kilowatt is equal to 1,000 watts.

To calculate how much energy a 100-watt panel can generate where you live, you can use a resource like the Global Solar Atlas, which provides location-based data for sunlight hours, power potential and optimal panel installation angles.

According to the Global Solar Atlas, you can generate an average of 4.4 kilowatt-hours (kWh) of electricity per day for every kilowatt (kW) of solar panels installed in sunny Orlando, Florida. That means you could produce approximately 0.44 kWh of electricity per day with a single 100-watt panel there.

On the other hand, if you were to go a few thousand miles northwest to Glacier National Park in Montana, your solar potential is closer to 3 kWh of electricity per day per kW of capacity installed. That means an average day of sunlight would yield approximately 0.30 kWh of electricity with a 100-watt solar panel.

Are 100-watt solar panels right for you?

Although 100-watt solar panels are great for many different uses, they're usually not the ideal choice for a large residential or commercial installation. However, if you can get your hands on some high-quality equipment at a great price, then 100-watt modules may be the best solar panels for:

  • Small, off-grid cabins, workshops and DIY projects
  • Remote outdoor lights, security features (cameras, gates, etc.) and water pumps
  • Accessories on recreational vehicles, camper vans, trailers and boats
  • Emergency and mobile power scenarios

If you're interested in converting your home to solar power, you may be better off working with a solar energy company that can design a solar panel system for your needs.

» MORE: Solar panel installation guide


How much do 100-watt solar panels cost?

Generally on the cheaper end of solar panel costs, 100-watt equipment is a budget-friendly choice for most buyers. Whether you buy them one by one or in bulk, 100-watt solar panels typically retail for anywhere from $75 to $200.

Do I need a battery for a 100-watt solar panel?

You technically only need a battery with your 100-watt solar panel if you would like to power your devices with solar power outside of sunlight hours. But that’s not all you’ll need.

For a complete, off-grid solar energy system that can power your devices 24/7, you’ll likely need:

  • A solar panel
  • A battery
  • A charge controller
  • An inverter

If you’re looking to power the kinds of small electronics compatible with 100-watt solar panels, you may be better off with a solar generator than assembling your own piecemeal system, though.

How many batteries do I need for a 100-watt solar panel?

Considering a 100-watt solar panel can generate about 400 watt-hours (Wh) of electricity per day in ordinary conditions, you will likely need a battery with at least 400 Wh of storage capacity to capture your average daily power potential.

How many amps does a 100-watt solar panel produce?

A 100-watt solar panel can produce anywhere between 5 and 8 amps during peak sunlight hours. This electricity can then be output at an amperage to meet your device’s requirements once it's processed by the other hardware components of your solar energy system.

Find a Solar Energy partner near you.

    ConsumerAffairs writers primarily rely on government data, industry experts and original research from other reputable publications to inform their work. Specific sources for this article include:
    1. Global Solar Atlas, “Map.” Accessed April 24, 2023
    Did you find this article helpful? |
    Share this article