Home energy guides

Watts vs. Watt-Hours

Learn the difference between power and energy and avoid a common battery-sizing mistake.

How to Read an Appliance Power Label

Find voltage, current, watts, and duty-cycle clues on an appliance label.

Battery Usable Capacity and Depth of Discharge

Understand why nominal battery capacity is not all available for routine use.

Why Inverter Efficiency Changes Runtime

See how conversion loss and inverter standby draw reduce AC runtime.

How to Find Your Electricity Rate

Use your utility bill to choose a meaningful price per kilowatt-hour.

Why Real Battery Runtime Differs from the Formula

Learn how load, temperature, age, cutoffs, and wiring affect measured runtime.