Glossary
kWh (kilowatt-hour)
A kWh (kilowatt-hour) is the energy a 1,000-watt appliance uses when it runs for one hour. It is the unit FPL, Duke and TECO use to measure and bill your consumption, and the same unit used to measure what solar panels produce.
What a kWh is
A kWh measures energy: power sustained over time. A 1,000-watt (1 kW) appliance running for one hour uses 1 kWh. A 100-watt appliance needs ten hours to use the same amount. Your bill adds up every one of those uses across the month and expresses the total in kWh.
Do not confuse kWh with kW. A kW tells you how much power an appliance draws at a given instant; a kWh tells you how much energy it used in total. A solar system is sold in kW, but what lowers your bill is the kWh it produces.
Why it matters in Florida
In Florida, air conditioning dominates consumption most of the year. A home here can use far more kWh than a same-size home in another state. Your bill does not rise only because the rate goes up; it rises because the number of kWh grows every summer.
When you evaluate solar, the starting point is not the size of your roof or the dollar amount on the bill. It is your kWh over the last 12 months. That number determines how much the system needs to produce and what share of your consumption it covers (the offset). Without it, any proposal is a guess.
Common mistake
Looking only at dollars. Two $200 bills can hide very different usage, because part of the amount is the minimum charge and fixed fees that panels never remove. Always ask for the kWh history (it is on the bill or in your utility’s online account) before comparing proposals. The guide what is a kWh and how much your home uses shows you how to read it.
Full guide: What is a kWh and how much does a Florida home use (2026) →
Updated