The Basic Parts of an Off-Grid Solar System
An off-grid system always has five core components:
- Solar Panels
- Charge Controller
- Battery Bank
- Inverter
- Wiring, Fuses & Disconnects (Safety Gear)
Optional but common:
- Generator or shore power backup
- Monitoring display or app
1. Solar Panels – Make the Power
What they do:
Solar panels turn sunlight into electricity (DC power).
How they operate:
- Sun hits the panels
- Panels produce electricity whenever there is light (more sun = more power)
- Power flows out of the panels toward the charge controller
Think of them as:
As a fuel pump on your car pumping electricity to your batteries
2. Charge Controller – Protects the Batteries
What it does:
Controls how power from the panels goes into the batteries so they don’t get damaged.
How it operates:
- Takes power from the panels
- Adjusts voltage and current
- Stops charging when batteries are full
Two types:
- PWM – basic, cheaper
- MPPT – more efficient, common in modern systems
Think of it as:
As a water valve to prevent overfilling but filling the batteries as fast as possible
3. Battery Bank – Stores the Power
What it does:
Stores electricity so you can use power at night or when it’s cloudy.
How it operates:
- Charges during the day
- Discharges when you use power
- Feeds power to the inverter
Common battery types:
- Lead-acid (older, heavier)
- AGM (sealed lead-acid)
- Lithium (LiFePO₄) – most popular now
Think of it as:
A storage tank for your electricity.
4. Inverter – Makes Power Usable
What it does:
Converts battery power (DC) into household power (AC).
How it operates:
- Pulls DC power from batteries
- Converts it to 120V AC (or 240V)
- Powers outlets, appliances, and electronics
Types:
- Pure sine wave – required for modern electronics
- Modified sine wave – outdated, avoid
Think of it as:
A translator between your batteries and your appliances.
5. Wiring, Fuses & Disconnects – Keeps Everything Safe
What they do:
Protect equipment and people from short circuits, overloads, and fire.
How they operate:
- Fuses blow if power exceeds safe limits
- Disconnects allow you to shut the system off
- Proper wire size prevents overheating
Think of them as: A seatbelt of circuit breaker to protect you and your system
The Buchanan's Rolling Down The Road 