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 Caterpillar power system for your needs


Let’s power up your knowledge and boost your purchasing confidence.


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 and Three-Phase Systems)


🔹 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 and KW


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 Caterpillar 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 Caterpillar inventory


American Energy Solutions – Your Trusted Name in Industrial Backup Power

Powering Data. Powering Growth. Powering You.