Gear

Calculating Your RV or Van Solar Needs

By Jennifer Jennings

To harness the sun’s power for your van life needs, you can create your own solar power grid by combining the basic components: – Solar panels – Batteries – A charge controller – A power inverterr

Things can get a little bit confusing when you’re trying to figure out exactly how much solar power you need.

Decide what devices you will need to power.

Your van or RV may have electronics that are powered by 120V AC or 12V DC.

1

Decide what devices you will need to power.

This information, and how much power they consume, should be listed on the device or in the user manual.

1

Estimate Your Maximum Watt-Hours

You’ll need to decide how long you plan to use each appliance per day, figure out the watt-hours for each device, and then add them all together.

2

Estimate Your Maximum Watt-Hours

2

Calculate power consumption: volts x amps = watts

12 volt DC 2 Amp fan

12V X 2A = 24W

Estimate Your Maximum Watt-Hours

2

Determine watt-hours per device: watts x usage (in hours) = watt-hours

24W fan runs 4 hours a day.

24W X 4 = 96Wh

Estimate Your Maximum Watt-Hours

2

Figure out the total for all devices: device 1 + device 2 + device 3 = daily watt-hour consumption

Try a Battery Monitor Instead

3

Another option for more straightforward calculation is to purchase a battery monitor and spend a day camping using your normal amount of power usage.

Calculate Necessary Panels

4

Solar panels are sold based on their power output, typically between 100 and 400 watts.

Calculate Necessary Panels

4

However, these numbers are the max output, so you must remember that this is how much a panel can produce in full sun with nothing affecting its efficiency.

Calculate Necessary Panels

4

You’ll need to estimate how many hours of full sun you expect your panels to get.

Calculate Necessary Panels

4

For some people, this may be around 3-4 hours per day, while others may expect 6-8.

Calculate the total solar panel watts needed:

4

daily watt-hours / sunlight hours = total solar panel watts needed

5 hours a day

2000Wh / 5H = 400 Watts of solar needed

Example

2000Wh needed

Determine the total number of panels required:

4

total solar panel watts needed / individual panel watts = number of panels needed

400Watts / 200 watt panels = 2 panels needed

5

Keep the batteries, charge controller, and inverter in mind.

Portable solar panels often come in a package. If you buy them separately, you’ll need to research the components to make sure all parts are compatible.

Get an in-depth look with the extended article version on Vanlifers