OffGridCalcs is built and maintained by a former ship captain. A ship at sea is the original off-grid system: battery banks, generators, charging regimes and a strict energy budget, with no utility to fall back on and real consequences for getting the numbers wrong. That background shapes how these tools are written, conservative assumptions, losses counted, worst-month thinking.
Every calculator on this site shows its formula and states its assumptions, because a number you can't check is a number you can't trust. The tools are free, run entirely in your browser, and collect nothing.
These calculators are planning estimates. Final designs should be confirmed against component datasheets, manufacturer guidance and the electrical code that applies where you build.
Contact
Corrections and suggestions are welcome: info@offgridcalcs.com