What Can a 500 Watt Solar Panel Run?

With the rising popularity of solar energy, many people are now turning to solar power to power their appliances and electricity needs.

But not all solar panels are created equal – the wattage of a solar panel plays a big role in determining what it can actually run.

In this article, we’ll look at what a 500-watt solar panel can do, how much power it can generate, and what kind of appliances you can power with it.

Key Takeaways

• The dimensions of a 500-watt solar panel are around 86.61 inches by 43.31 inches and it weighs approximately 71.2 lbs.
• The 500-watt solar panel generates about 2,537 Wh per day but this still depends on your location and the number of hours of peak sunlight.
• A 500-watt can run a variety of household items such as laptops, electric fans, lights, and even some small appliances.
• You need a 274Ah battery bank with 12V and 80% DoD to store the energy generated by a 500-watt solar panel.
• You need a 52.1A charge controller to regulate the current and voltage coming from a 500-watt solar panel.
• You need an 840W inverter to convert the DC from the batteries into AC power to run the household appliances.
• A 500-watt solar panel costs around $0.25/watt but this does not include the costs of installation and other components.

What Is a 500-Watt Solar Panel?

Before we dive into what a 500-watt solar panel can do for you, let’s first discuss what a 500-watt solar panel is.

Solar panels are rated in watts, which measures the amount of power the panel can generate under STC (Standard Test Conditions).

In other words, a 500-watt solar panel will produce 500 watts of power in an hour when the sun is at its peak strength with solar irradiance of 1,000W/m².

To rate a solar panel, manufacturers use a very expensive device that simulates sunlight and they direct this light through the solar panel.

Then, they test the output to determine the panel’s wattage rating.

How Much Power Does a 500-Watt Solar Panel Produce?

To know how much power a solar panel produces, you need to find out the number of peak sun hours in your geographic area.

This number can vary quite a bit depending on the season and location – you can use the National Renewable Energy Laboratory’s PVWatts calculator to get an estimated value for your area.

I live in northern California, so I will use 5.9 hours of peak sun hours for our example.

You can use this formula to figure out how much energy your 500-watt solar panel will generate per day:

Solar Panel Power Output (Wh) = Solar Panel’s Rated Wattage (W) x Number of Peak Sun Hours (h)

So, for our example:

Solar Panel Power Output (Wh) = 500W x 5.9 hours = 2,950 Wh/day

But this is just the theoretical maximum output of your 500-watt solar panel.

In reality, due to shading, dust accumulation, and other factors, you may get a lower amount of energy from your solar panel.

These losses can be as high as 14%, so we can account for them by following this formula:

Solar Panel Power Output (Wh) = Solar Panel’s Rated Wattage (W) x Number of Peak Sun Hours (h) x (1-0.14)

For our example:

Solar Panel Power Output (Wh) = 500W x 5.9 hours x (1-0.14) = 2,537 Wh/day

What Will a 500-Watt Solar Panel Run?

Now that we have determined the amount of energy that your 500-watt solar panel can produce in a day, let’s see what it can power.

We can do this by looking at the wattage of various devices you may want to run and comparing it to the total output of your solar panel.

To do so, we’ll use the following formula to determine how many hours a device can run on your 500-watt solar panel:

Appliance Required Power (Wh) = Appliance Power Rating (W) x Number of Hours Used (h)

Now, let’s look at a few examples.

If we assume that you want to run a 65W laptop on solar energy for 4 hours, the total amount of energy required will be:

Appliance Required Power (Wh) = 65W x 4h = 260Wh

So, will a 500-watt solar panel be able to run this laptop for 4 hours?

Yes! Our 500-watt solar panel will generate 2,537 Wh/day and since the laptop requires only 260Wh, it can easily be powered for 4 hours with our solar panel. 

But most importantly, how many hours exactly will our 500-watt solar panel be able to run the laptop?

To figure this out, we can use the following formula:

Number of Hours Possible = Solar Panel’s Daily Output (Wh) / Appliance Required Power (Wh)

For our example: 

Number of Hours Possible = 2,537Wh / 260Wh = 39 hours

Let’s assume you have a solar shed that contains a TV, a small refrigerator, 3 LED lights, a laptop, a fan, a coffee maker, a phone charger, and a Wi-Fi router.

To answer this question, you need to construct a table that contains the wattage of each appliance, and how many hours it will be used per day:

Since the total wattage of all these devices is 2,520Wh and the 500-watt solar panel can produce 2,537Wh/day, it should be able to run these appliances for an entire day.

How Many Batteries Do I Need for a 500-Watt Solar Panel?

We’ve been talking about a 500-watt solar panel and its power output, but to really make use of that power, you need batteries.

The solar panel isn’t reliable to power appliances directly as they don’t provide a steady flow of electricity, and the power output can vary greatly from day to day or even within a single day.

That’s why you need batteries to store that energy so that you can use it whenever you need it.

But how many batteries do you need for a 500-watt solar panel?

To calculate this, you can use this formula:

Battery Size (Ah) = Solar Panel Daily Output (Wh) / Battery’s Voltage (12/24V) / DoD (0.5/0.75/0.8)

We know that our 500-watt solar panel can produce 2,537 Wh per day.

Let’s assume that you are using a 12V battery with an 80% Depth of Discharge (DoD).

So, the required battery size for our example will be:

Battery Size = 2,537Wh / 12V / 0.8 = 274 Ah

Therefore, to store the power generated by a 500-watt solar panel, you’ll need a 274 Ah battery with a 12V voltage and an 80% DoD.

What Size Charge Controller for a 500-Watt Solar Panel?

Connecting the solar panel directly to the battery can overcharge it, resulting in permanent damage to the battery.

That’s why you need a charge controller.

It’s responsible for regulating the current and voltage coming from the solar panel, making sure that the battery is charged properly and doesn’t get overcharged.

To know what size charge controller you need for a 500-watt solar panel, you can use this calculator.

For my example, I selected the following options:

• Battery Voltage: 12V
• Solar Panel Wattage: 500W
• Solar Panel Voltage: 24V

The result is that I need a 52.1A charge controller for my 500-watt solar panel.

I recommend that you go for an MPPT charge controller as it’s more efficient than a PWM charge controller and can help you get the most out of your solar panel.

What Size Inverter for a 500 Watt Solar Panel?

The solar panel generates DC power, but most appliances and electronic devices require AC power to function.

Therefore, you need an inverter to convert the DC power from your solar panel into AC power so that you can use it with these devices.

If we’re talking about a grid-tied solar system, you should multiply the DC rating by 1.15 to calculate the size of the inverter required.

So, for our 500-watt solar panel, the required inverter size will be 1.15 x 500W = 575W.

However, we’re using a small off-grid solar system, so the best way to calculate the size of the inverter is to find out the total wattage of all the appliances that you’ll be running.

In our example, we can use this formula to calculate the total wattage:

Solar Inverter Size (W) = Sum of All Appliance Wattages Running at the Same Time

Solar Inverter Size (W) = 80W + 75W + 5W + 65W + 50W + 550W + 5W + 10W = 840W

This means that we need at least an 840W inverter to power all of our appliances.

Note: Some appliances like solar air conditioners require a large startup power. So make sure your inverter specifications have a larger surge power than your largest appliance.

How Much Does a 500-Watt Solar Panel Cost?

According to NREL Solar Photovoltaic System, and Energy Storage Cost Benchmarks Q1, 2022 document, the cost of a 500-watt solar panel is around $0.25/watt.

So, the cost of the 500-watt solar panel is $125.

However, this does not include the cost of batteries, a charge controller, an inverter, and all the other components that you’ll need for your off-grid solar system.

You should also factor in installation costs if you’re getting the system installed by a professional.

FAQs

Conclusion

As promised, we have discussed everything you need to know about a 500-watt solar panel.

We started with the basics and then moved on to discussing the type of charge controller, inverter, and battery that you’ll need for your off-grid solar setup.

Do you still have questions about the 500-watt solar panel?

Feel free to ask them in the comments section and we’ll be more than happy to answer them for you.