PV Plus – Solar Panel Array Size Calculator
Estimate how many solar panels you need based on your daily energy use.
Tip: Monthly kWh ÷ 30 ≈ daily kWh Select the wattage of the solar panel being considered. Central CA typically ranges from 5–6 sun hours depending on tilt and shade.Example Result:
System Size: 8.8 kW
Panels Required: 22
What this means:
• This system could produce about 12,000–14,000 kWh per year in Central California.
• This would typically offset $180–$240/month of electricity depending on your utility.
• The roof area required would be approximately 430–450 sq ft.
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.
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.
Common Solar Myths
Myth: Solar works only in hot climates
Reality: Solar panels produce electricity from light, not heat.
Myth: Solar stops working in winter
Reality: Production is lower but systems still produce power.
Myth: Batteries are required
Reality: Most grid-tied homes don’t need batteries.
