About SolarMathKit

Why this site exists

Many battery and solar calculators return a clean number while hiding the assumptions that made it. That is especially unhelpful when a small change in depth of discharge, inverter loss, or peak sun hours can change the hardware count.

SolarMathKit keeps those inputs visible. The first release focuses on seven tasks: battery sizing, runtime, backup loads, series-parallel layouts, solar array sizing, panel output, and RV system planning.

How calculations are built

The formulas live in pure TypeScript modules, separate from the page components. The backup and RV tools call the same battery and panel modules as the dedicated calculators. This avoids maintaining several versions of the same formula.

Tests cover published examples, invalid percentages, incompatible module voltages, whole-device rounding, and relationships such as lower efficiency never reducing required capacity.

Editorial principles

• Presets are labeled as editable starting points, not specifications.
• Results distinguish rated, usable, and installed capacity.
• Hardware counts round upward and show the rounding step.
• Pages avoid prices, incentives, and legal claims that would need constant regional updates.
• No page claims expert verification or credentials that do not exist.

What SolarMathKit is not

This site does not produce a final electrical design, quote, permit package, or safety certification. It does not select wire, protection devices, grounding, an inverter, a charge controller, or structural mounting.

Use the numbers to frame a discussion and compare scenarios. Check every final choice against equipment manuals, site conditions, local rules, and a qualified professional.

How to report a problem

If a formula, example, or explanation looks wrong, send the page URL, the exact inputs, the result you received, and the result you expected through the contact page. Reproducible reports are the fastest to verify.