Amperage vs Kilowatts: What’s the Difference and Why It Matters for Generator Sizing

A Power Buyer’s Guide from American Energy Solutions, Inc.

Understanding the difference between amperage (amps) and kilowatts (kW) is critical when it comes to choosing the right backup power system. At American Energy Solutions, we work with clients every day—across industries like data centers, dairies, aggregate plants, cannabis grow operations, and disaster relief—who are trying to size and source the correct industrial generator to protect their operations.

In this guide, we’ll break down:

• The key differences between amps and kilowatts
• How to calculate amps to kilowatts and vice versa
• Why these calculations are essential for generator sizing
• How AES, Inc. can help you choose the most reliable new, surplus, used or rebuilt power system for your needs

What Is Amperage (Amps)?

Amperage refers to the amount of electrical current flowing through a system. Think of it like water flowing through a pipe—the more amps, the more “flow” of electricity you have.

Amps are important because:

• They help determine wire size, breaker ratings, and load balance
• Overloaded amperage can cause overheating, fire hazards, or generator shutdowns
• Understanding amps helps ensure your generator output matches your equipment’s demand

What Is Kilowatt (kW)?

Kilowatts are a measurement of real power—the amount of electrical power that actually gets used by equipment to do work, such as running:

• HVAC systems
• Electric motors
• Compressors
• Pumps
• Servers
• Refrigeration units
• Lighting systems

1 kilowatt (kW) = 1,000 watts
This is the metric most often used to define a generator’s capacity.

Key Difference

• Amperage (amps) measures flow of electricity
• Kilowatts (kW) measures the rate of energy use

They’re connected by voltage and power factor, especially in AC systems.

How to Convert Amps to Kilowatts

Single-Phase Equation:

kW = (Amps × Volts × Power Factor) / 1,000

Three-Phase Equation:

kW = (√3 × Amps × Volts × Power Factor) / 1,000

Where:

• Volts = system voltage (typically 120V, 240V, 480V, etc.)
• Power Factor (PF) = efficiency (usually 0.8 for industrial generators)

Why It’s Crucial for Generator Sizing

Selecting a generator based on amperage without converting to kilowatts can result in:

• Undersized generators that trip under load
• Overloaded power systems
• Costly system failures
• Wasted money on oversized units
• Code violations or failed inspections

At American Energy Solutions, we eliminate the guesswork by using real-world load profiles, surge factor considerations, and voltage-specific generator sizing tools to get you the right power system the first time.

Backed by AES Inc.

Whether you need a standby diesel generator for a cold storage warehouse or a prime-rated natural gas unit for remote off-grid construction, we have the inventory and knowledge to deliver.

• Used and refurbished Caterpillar, Cummins, Kohler, MTU, Gillette, and Multiquip gensets from 20kW to 4000kW
• Both 1-phase and 3-phase configurations
• Customizable voltage and frequency output (60Hz/50Hz)
• Load bank tested and guaranteed performance
• Mobile trailer-mounted and permanent skid options available

We don’t just sell power—we help you measure it, plan it, and protect your operation.

Tools to Help You Convert Amps to Kilowatts

At AES, we use industry-standard tools like:

• Generator sizing calculators
• Amps-to-kW conversion charts
• Custom load analysis spreadsheets
• On-site amperage logging equipment
• Power factor correction audits

Want help doing the math? Reach out and we’ll size your system in minutes.

Common Applications and Recommended Generator Sizing

Industry / Use Case	Typical Voltage	Load Size	Suggested Generator Size
Cannabis Grow Operation	208V / 240V	120A	25–40 kW
Aggregate Plant	480V (3-phase)	200A	125–150 kW
Cold Storage Facility	240V / 480V	180A	100–125 kW
Remote Construction Site	480V / 600V	250A	175–200 kW
Dairy Operation	208V / 240V	100A	20–40 kW

Note: Always account for surge (starting) loads and reserve capacity when choosing a unit.

Trust American Energy Solutions for All Your Power Needs

Choosing a reliable generator set isn’t just about picking the biggest unit—it’s about understanding the math behind amperage, kilowatts, and voltage.

At American Energy Solutions, we make it simple.

• We help you calculate amps to kilowatts correctly
• We recommend the best generator for your facility
• We supply top-tier new, surplus, used and rebuilt generators at competitive prices
• We provide load testing, commissioning, and maintenance nationwide

Don’t Guess—Calculate and Choose with Confidence

If you're ready to find the perfect backup power system, contact our expert team today and let us help you convert the amps to kilowatts, size your load, and protect your business from outages, downtime, and disaster.

📞 Call now to speak to a power expert
📧 Email us your amperage or load profile
🌐 Visit www.americanenergysolutions.com to browse our full power systems inventory