Answer a few questions about your home and appliances — no electrical knowledge needed. For each appliance, pick Low/Medium/High if you're not sure of its exact power draw (shown in watts), or type your own value if you know it. Running totals update live at the bottom of the page as you go.
Your progress is automatically saved in this browser, so you can close the page and come back later. Clear my saved data
Daily energy = sum of (quantity × hours/day × power) for every appliance. Peak demand applies a simultaneity factor of 70% to non-essential loads (not everything runs at once). Solar array size = daily energy ÷ (peak sun hours × 0.80 system efficiency, accounting for wiring, inverter and temperature losses). Battery storage = daily energy × autonomy days ÷ 0.80 usable depth-of-discharge (typical for lithium batteries). Inverter size = peak demand × 1.25 safety margin. These are general planning estimates, not final engineering figures.