How Many Solar Panels Do You Actually Need?

A lot of people ask us this question. The honest answer is: it depends on what you want to power. But we can give you a framework to figure it out yourself in about 10 minutes.

Step 1: Know your daily power use

Start with the appliances you want to run. Write down each one and how many hours per day you use it. Multiply wattage x hours = watt-hours per day.

Common examples:

• LED lights (10 bulbs): 60W x 5 hours = 300Wh
• Refrigerator: 150W x 8 hours = 1,200Wh
• Phone/laptop charging: 50W x 2 hours = 100Wh
• Well pump (1/2 HP): 370W x 1 hour = 370Wh

Add them up. That is your daily load.

Step 2: Account for eastern Washington sun hours

Oroville and the Okanogan Valley average about 5-6 peak sun hours per day in summer, dropping to 3-4 in winter. For a year-round system, plan around 4 peak sun hours.

Step 3: Do the math

Daily load / peak sun hours = panel wattage needed

Example: 2,000Wh / 4 hours = 500W of panels

At 300W per panel, that is 2 panels for a basic off-grid setup — more if you want battery storage buffer.

Our recommendation

For most eastern WA homesteads and cabins, a 4-6 panel setup with battery storage covers the basics comfortably. Our 300W used panels at $90 each make this affordable.

Come out to the depot in Oroville and we will walk through your setup with you.