WHAT IS THE DIFFERENCE BETWEEN KW AND KWH?

When working with lithium-ion batteries—like Vanguard batteries—you’ll often hear terms like watts, watt-hours, kilowatts (kW), and kilowatt-hours (kWh). These terms sound similar but refer to very different things: one is power, the other is energy.

• A watt is a measure of instantaneous power — the rate at which energy is being used or produced.

• Determines what loads it can handle at once (performance).

• 1 kilowatt (kW) = 1,000 watts (W).

Simply put: “A watt is a measurement of power, so think of it like horsepower... It’s the amount of work being done at a moment in time.”

• A watt-hour is a measure of energy capacity — how much energy is stored or consumed over time.
  

• Determines how long your equipment runs (duration).

• 1 Wh means using 1 watt of power for 1 hour.

• 1 kWh = 1,000 Wh = using 1,000 W for 1 hour (or 500 W for 2 hours, etc.)

Simply put: “A watt-hour is using a watt for an hour… like running at 10 kilometers an hour — you’ve traveled 10 kilometers after an hour.”

When sizing or selecting a lithium-ion battery like Vanguard NMC, both values are equally important:

• 🔋 kWh (energy) tells you how long your equipment can run (battery capacity).

• ⚡ kW (power) tells you how much power it can deliver at once (e.g. during startup or peak load).

For instance:

“You might need 10 kWh of energy for your application, but only 1 kW of power at any time.”

• A battery with 10 kWh capacity and 1 kW power rating will run a 1 kW device for 10 hours.
• But it won’t work if your device needs 5 kW of power suddenly—even for a moment—unless the battery supports it.

• Wh/kWh = energy stored or consumed over time
• W/kW = power at any given moment
• Both are critical for matching a battery to an application—capacity for duration, power for performance.