UnitsUp to date · Jan 15, 2026

kWh (Kilowatt-hour)

A unit of energy equal to 1,000 watts used for one hour. This is how utilities measure your electricity usage.

Why It Matters

Every line on your electric bill is priced per kWh. Understanding this unit lets you compare costs, judge solar system sizes, and track savings.

Running a 100-watt light bulb for 10 hours uses 1 kWh. The national average price is about 16¢ per kWh.

Watt (W)

A unit of power equal to one joule per second. Solar panels are rated in watts (W) or kilowatts (kW = 1,000W).

Load Profile

A pattern of your electricity usage throughout the day and year. Important for sizing solar and battery systems.