Gizmo Solar Calculator

Enter your monthly kWh above (fastest) — or add appliances below. Both sync to all tabs.

Appliance	Watts	Hrs/day	Qty	Wh/day

Daily energy (Wh/day)

Peak sun hours (h/day)

System voltage (V)

Panel wattage (W)

System efficiency (%)

Location / climate

🔋 Hybrid / Off-grid — include battery recharge in panel sizing

Daily energy (Wh/day)

Backup days

Depth of discharge (%)

Battery type

System voltage (V)

Battery cell voltage (V)

⚡ How to use: Enter your base load (lights, TV, fans, etc.) then add your biggest motor appliance below. Motors need 2–5× their rated watts to start — this "surge" drives inverter sizing.

🏗️ System type

Base load (W) — all appliances except high-surge

Inverter efficiency (%)

System voltage (V)

Safety buffer (%)

🔋 Battery charging (hybrid / off-grid)

🔌 In hybrid/off-grid, the inverter must simultaneously power your loads AND charge the battery bank. The charging power is added to the load when sizing the inverter — and the panels must generate enough to cover both.

Battery bank capacity (Wh) synced

Target charge time (h) sun hours available

Charge efficiency (%)

Est. charge power needed (W)

⚡ High-surge appliance (motor, compressor, pump)

🔎 What is surge? Motors (AC units, pumps, refrigerators) draw 2–5× their rated watts for 1–2 seconds when starting. Your inverter must handle this peak — or it will shut down or trip.

Appliance name

Rated watts (running)

Startup multiplier (× rated watts)

Estimated startup peak (W)

🇵🇭 Pre-loaded with Philippine cities. All PH locations face South (Northern Hemisphere).

Select Philippine city / region

Metro Manila

Lat 14.60°N · Northern Hemisphere · Faces South

Northern PH

Latitude (°N)

Season / optimization

💡 Currency in Philippine Peso (₱). Average Meralco rate ≈ ₱11–₱12/kWh.

System cost (₱)

Monthly bill (₱)

% bill offset by solar

Annual rate increase (%) — Meralco

Feed-in tariff (₱/kWh)

System size (kWp)

Annual degradation (%)

Incentives / rebates (₱)

⚡ Inverter size & voltage auto-sync from the Inverter tab. Panel count & wattage sync from Panels tab. You can edit any field manually.

🔗 Values synced from Inverter & Panels tabs

System Parameters

Inverter wattage (W) synced

System voltage (V) synced

No. of solar panels synced

Panel wattage (W) synced

Panel VOC (V) — open circuit

Wire run distance (m)

📐 Enter component details below, select a system type, then tap Generate Diagram. The diagram will show how to wire panels and batteries (series / parallel / series-parallel).

🔌 Inverter Details

Brand / Model

Rated power (W)

System voltage (V)

Max PV input voltage (V)

MPPT voltage range — min (V)

MPPT voltage range — max (V)

☀️ Solar Panel Details

Brand / Model

Panel wattage (Wp)

Voc — open circuit voltage (V)

Vmp — voltage at max power (V)

Isc — short circuit current (A)

Imp — current at max power (A)

Total number of panels

🔋 Battery Details

Brand / Model

Nominal voltage (V)

Capacity per unit (Ah)

Total Ah needed

🏗️ System Type

Gizmo Solar Calculator

Daily load summary

Protection & Wiring Recommendations