How to Use our Solar DC to AC Ratio Calculator

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• Enter four numbers (or slide):

  1. DC Array (W) – combined wattage of all panels

  2. Inverter (W) – continuous AC output of your inverter

  3. Panel Wattage (W) – size of a single panel (used to count panels)

  4. Sun‑Hours (h/day) – average full‑sun hours at your site

• Watch the bars move – they resize in real time so you can see whether the array is larger or smaller than the inverter capacity.

• Click “Next” to get:
  • Your DC‑to‑AC ratio (ideal is about 1.2 : 1)
  • Approximate number of panels needed
  • Estimated annual kWh production
  • Any clipping loss if the array overshoots the inverter

• Interpret the ratio:
  • Below 1.1 → inverter has headroom; consider adding panels
  • 1.1 – 1.3 → sweet‑spot efficiency
  • Above 1.3 → expect some power clipping on bright days

FAQ: Sizing Your Solar Array & Inverter

What is the DC‑to‑AC ratio?

It’s the nameplate DC power of your PV array divided by the AC rating of the inverter. Designers use it to see whether panels or inverter will be the bottleneck.

What’s the “sweet‑spot” ratio for home & small‑commercial systems?

Most studies and design guides land around 1.1 – 1.3 : 1—big enough to keep the inverter busy, small enough to avoid major clipping losses.

What if I oversize the array (ratio > 1.4)?

You’ll gain early‑morning / winter kWh but can lose 2‑5 % of annual energy to inverter clipping on very bright days, and you’ll run the inverter hotter.

What is inverter clipping?

Inverter clipping happens when your PV array is producing more DC power than the inverter’s AC output rating can pass through at that moment. The inverter self‑limits, “clipping” the power curve so everything above its nameplate capacity is lost.

Does adding batteries change the target ratio?

Yes. With storage to soak up midday surplus, ratios up to 1.6 : 1 can make sense without wasting energy.

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