Off‑Grid Power Sizing Guide

Understand what your home really needs before you buy.

The 3‑Part Off‑Grid Power System

A reliable off‑grid home runs on three components:

1. Solar Panels — Energy In

Your panels collect energy during the day. Typical size: 6–12 kW Estimated cost: $6,000–$18,000

2. Battery Bank — Storage

Your batteries run the home 24/7. Typical size: 10–20 kWh Estimated cost: $6,000–$16,000

3. Backup Generator — Reliability

Cloudy weeks happen. Backup fills the gaps. Typical size: 4–12 kW Estimated cost: $1,500–$6,000

System Flow: Energy In → Storage → Backup

How to Estimate Your Daily Usage

Your daily energy use is the foundation of your entire system.

Daily kWh Usage Categories

• Low: 5–10 kWh/day (small cabin, minimal appliances)

• Medium: 10–20 kWh/day (typical off‑grid home)

• High: 20–40 kWh/day (AC, well pump, freezer, workshop)

What Affects Usage Most

• HVAC (mini splits, heaters)

• Well pumps

• Refrigeration

• Freezers

• Electric cooking

• Laundry

• Standby loads (routers, chargers, electronics)

Simple Worksheet

Use this table to estimate your daily consumption:

Add up your total kWh/day → move to the next section.

Recommended System Sizes

These are realistic, experience‑based ranges — not marketing numbers.

Small Cabin (5–10 kWh/day)

• 4–6 kW solar

• 8–12 kWh battery

• 3–5 kW generator

Standard Off‑Grid Home (10–20 kWh/day)

• 6–10 kW solar

• 12–20 kWh battery

• 5–8 kW generator

High‑Demand Home (20–40 kWh/day)

• 10–16 kW solar

• 20–40 kWh battery

• 8–12 kW generator

3‑Step Sizing Tool

Use this simple 3‑step guide to estimate your system needs.

Step 1 — Choose Your Daily Usage

• Low (5–10 kWh)

• Medium (10–20 kWh)

• High (20–40 kWh)

• Custom entry

Step 2 — Choose Your Climate

• Mild

• Mixed

• Cold / Cloudy

• Extreme Winter

Step 3 — Select Your Appliances

• Well pump

• Mini split

• Freezer

• Electric cooking

• EV charging

• Workshop tools

Your Estimated System Output Will Include:

• Recommended solar size (kW)

• Recommended battery size (kWh)

• Recommended generator size

• Estimated cost range

• Links to matching systems

• Link to download the PDF

• Link back to this full guide

Total System Cost Range

A complete off‑grid power system typically falls between:

$12,000 – $40,000

What Drives Cost Up or Down

• Daily kWh usage

• Winter performance needs

• Roof vs. ground mount

• Number of days of autonomy

• Appliance load

• Battery chemistry (LFP vs AGM)

Next Steps

Download the PDF Guide

A clean, printable version of this guide.

Use the 3-Step Sizing Tool

Shop Off‑Grid Power Systems

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