Reviewed August 2026 · General information
Battery capacity, solar input and inverter rating describe different parts of the electrical system. Off-grid duration depends on energy consumed, energy recovered and the operating limits of every component.
The four useful units
- Volts (V)
- Electrical system pressure; Ultimate systems may contain more than one voltage domain.
- Amps (A)
- Instantaneous current flow.
- Amp-hours (Ah)
- A battery-capacity measure that must be interpreted with system voltage and usable limits.
- Watt-hours (Wh)
- Energy consumed or stored; watts multiplied by hours.
Build a daily energy budget
| Load | Estimate |
|---|---|
| Refrigeration | Average daily energy, not only compressor rating |
| Lighting and pumps | Power × expected running time |
| Fans, electronics and communications | Include standby and charging losses |
| Inverter appliances | AC watts plus conversion losses |
| Induction cooking | High short-duration demand; verify battery and inverter compatibility |
Plan for poor solar days
Solar output changes with season, latitude, cloud, heat, shade, orientation and panel cleanliness. Maintain a reserve and understand alternative charging from the tow vehicle or mains.
Authoritative sources
Specifications and regulations can change. Check the latest applicable material before making a towing or safety decision.
Want advice around your own setup?
Bring your tow-vehicle details, intended trips and likely load so the conversation can start with the complete combination.
Talk to the team