As you begin preparing to convert your home to solar energy, there’s a lot to wrap your head around: panels, batteries, inverters, and more. What you’ll soon discover is that 300 watts is the most common size of solar panel available, and you’ll probably come up with a plan to use 300w solar panels in your own setup. But as you’re getting started you might wonder: what can a 300 watt solar panel run?
A single 300 watt solar panel is strong enough to power a few appliances, but in this post you’ll learn how to calculate the watts each appliance needs so you can determine if a single panel will be enough – or if you’ll need multiple panels. (Spoilers: you’ll very likely need multiple panels to run a full household of appliances! Read more about powering air conditioning and refrigerators with solar panels.)
After reading, you’ll have a sense for how to compare the energy generated by a 300 watt solar panel with the energy needed for each appliance in your home. You’ll then be able to calculate exactly how many solar panels you need for your own household needs. Read on to learn what a 300 watt solar panel runs, including specific appliances you can power with a single 300w solar panel.
Calculating Output from a 300 Watt Solar Panel
A 300 watt solar panel generates 300 watts of energy for one hour of direct sunlight. For an average of 8 hours of daylight, each 300 watt solar panel will generate 2.4 kWh per day, or 72kWh per month.
Your solar output will vary based on the weather and daylight you receive, so you may get more or less than this 72kWh output per month.
Calculating Needs from Your Appliances
In most cases, it’s easy to find out how many kilowatt hours each appliance in your home uses. Here are some monthly kWh estimates for common appliances:
- Refrigerator (without Ice Maker) – 33 kWh
- Refrigerator (with Ice Maker) – 39 kWh
- Microwave – 22 kWh
- Dishwasher – 36 kWh
- TV – 45 kWh
- Laptop Computer – 6.25 kWh
- Desktop Computer – 16 kWh
- Furnace Fan – 64 kWh
- Ceiling Fan – 46 kWh
Obviously these are just estimates and your own appliances may vary, but the good news is that most appliances are getting more efficient over time.
To determine your daily usage, you would divide each of these numbers; for example, a refrigerator with ice maker uses 1.3 kWh per day, and a TV uses 1.5 kWh per day.
What Can a 300 Watt Solar Panel Run?
Throughout this article, we’ve used kilowatt hours per month as a way to compare between the output of an average 300w solar panel and the needs of your appliances.
However, most of us care about energy usage on a day-to-day basis – we don’t ask “can I run my refrigerator this month?” or “can I watch TV this month?” Instead we want to know that we have enough energy to run the refrigerator today, or tube out each evening.
Comparing your appliance needs to panel output on a daily basis, a single 300w solar panel is enough to run a few appliances, such as a laptop, microwave, and refrigerator (without ice maker) each day.
However, a 300w solar panel does not generate enough power to run all of your appliances each day. To power all of your household appliances, you will need several 300w solar panels.
How Many 300 Watt Solar Panels Do You Need?
Since a single 300 watt solar panel is not enough to run a full household of appliances, you’ll need to determine how many solar panels you need in your own setup.
As an example, here is a full household of appliances and their daily kilowatt hour usage:
| Appliance | kWh (Monthly) | kWh (Daily) |
| Refrigerator (with Ice Maker) | 39 | 1.3 |
| Dishwasher | 36 | 1.2 |
| Microwave | 22 | 0.7 |
| Laptops (2) | 13 | 0.4 |
| TV | 45 | 1.5 |
| 14 100w Bulbs | 168 | 5.6 |
| Furnace | 64 | 2.1 |
Based on an average daily energy need of 12.8 kWh per day, you would need six 300w solar panels (generating 2.4kWh per day) to power all of these appliances everyday.
Other Considerations with 300 Watt Solar Panels
Don’t forget, there are other things to keep in mind in building your system using 300 watt solar panels. Assuming they are 12 volt panels, you will need a 12 volt battery as part of your solar system. You’ll also need an inverter to ensure that you can run the appliances which require AC, such as microwaves and laptops, since the output from 300w panels is DC.
Have other questions about setting up your system with 300 watt solar panels and what 300 watt solar panels can run? Comment below.