PV Plus – Solar Panel Array Size Calculator

Estimate how many solar panels you need based on your daily energy use.

Tip: Check your utility bill (monthly kWh ÷ 30 ≈ daily kWh).
Use the panel rating from your proposal or spec sheet.
Central CA is often in the 5–6 hour range depending on tilt and shade.

How this calculator works

We start with your daily energy use (kWh) and divide by the daily energy a single panel can produce. Each panel’s effective power is de-rated by about 25% to account for real-world conditions (heat, wiring losses, inverter efficiency, and so on).

This tool is meant for quick planning. For a site-specific PV Plus design with shading analysis, roof layout, and equipment selection, contact us and we’ll build a full proposal.

PV+ Household Power Usage Calculator

Enter appliance name, wattage (W), and daily hours. The table will total your daily use in kWh.

Appliance Watts (W) Hours/day kWh/day
Total kWh/day 0.00

Formula: kWh/day = (Watts ÷ 1000) × Hours/day. Adjust entries for weekend/seasonal usage if needed.

Next step with PV+: Send us your total kWh/day and a photo of your electric panel. We’ll size solar + battery, estimate savings, and outline upgrade options.

FAQ

What’s a kWh, again?
A kilowatt-hour (kWh) is energy: 1,000 watts used for one hour. It’s the unit utilities use for billing.

Bill method vs. appliance method—when to use which?

  • Use the bill method for a quick planning number.
  • Use the appliance method when you’re sizing solar/batteries or diagnosing high usage.

How do I convert between kWh and battery amp-hours (Ah)?
Use: Ah = (kWh × 1000) ÷ System Volts (e.g., 2 kWh on 48V ≈ 41.7 Ah). Handy when matching energy needs to a battery bank.