Why Generator Size Matters More Than You Think
When it comes to investing in a standby generator, one of the most common—and essential—questions people ask is: “What size generator do I need?” Choosing the right size is about more than just power—it’s about performance, safety, efficiency, and long-term reliability. Whether you’re looking to keep your family comfortable during an outage or ensure your business operations never miss a beat, proper generator sizing is the first and most crucial step.
At Synergy Standby Solutions, we specialize in custom backup power systems for homes and commercial properties in San Antonio and the surrounding areas. In this guide, we’ll discuss the essentials of generator sizing, what factors to consider, and how our experts can help you choose the perfect fit.
Understanding Generator Capacity: kW, Load, and Runtime
Generators are typically rated in kilowatts (kW), a unit that measures electrical power. The more kilowatts a generator can handle, the more appliances or systems it can support during a power outage. But this isn’t just a numbers game—you need to factor in load requirements, startup wattage, and runtime expectations to ensure your generator doesn’t fall short when it matters most.
Here are a few key terms:
- Running Watts (or Continuous Load): The total amount of electricity your systems draw during regular operation.
- Starting Watts: Additional power needed to start motor-driven appliances like refrigerators, HVACs, or pumps.
- Load: The total demand placed on your generator. Exceeding this Load can lead to system failure or damage.
How to Size a Generator for Your Home
For residential use, generator sizing is all about lifestyle and priorities. Do you want to keep the lights and fridge on—or do you want full-home coverage, including AC, water heaters, and even pool equipment?
Common Home Power Loads:
- Refrigerator: 600–800 watts
- Central AC: 2,000–4,000 watts
- Electric water heater: 3,000–4,500 watts
- Lighting & outlets: 500–1,000 watts
- WiFi, TVs, and computers: 500–1,000 watts
Here’s a rough guide:
- Bare Essentials (Fridge, lights, outlets): 7kW–10kW
- Whole-Home Coverage (AC, appliances, complete circuits): 20kW–24kW+
It’s always best to consult a professional, especially for homes with multiple HVAC systems or electric heat, to avoid underestimating your power needs.
Sizing for Businesses: One Size Definitely Does Not Fit All
If you’re a business owner, you already know that downtime is expensive. The generator size you need depends on your building’s layout, equipment, and operational priorities.
Example Generator Needs by Industry:
- Restaurants: 25kW–50kW to power refrigeration, cooking equipment, POS systems
- Retail Stores: 20kW–40kW to support lighting, registers, security systems
- Medical Clinics: 50kW–100kW to back up life-saving equipment and HVAC
- Warehouses & Distribution Centers: 60kW–150kW depending on automation and refrigeration
- Offices: 20kW–60kW depending on server use, lighting, and communications
It’s not just about powering everything—it’s about prioritizing what must stay online to keep your business compliant, safe, and operational.
Why a Professional Load Assessment Is Key
While online calculators can provide a ballpark estimate, every property is unique. Our team at Synergy Standby Solutions performs detailed load assessments to identify:
- Peak usage periods
- Critical circuits vs. non-essential loads
- Surge requirements for large appliances or machines
- Fuel type and runtime goals
This allows us to recommend a properly sized system that meets your daily needs and emergency expectations without wasting money on excess capacity.
Get Expert Sizing & Installation from Synergy Standby Solutions
At Synergy Standby Solutions, we help homeowners and businesses throughout San Antonio determine the perfect generator size with precision. Our process includes:
- On-site evaluations
- Custom load analysis
- Turnkey installation
- Ongoing maintenance and support
You’ll never be left guessing—or in the dark.
Ready to Size Your Generator? Let’s Talk.
The right generator size is essential for safety, reliability, and peace of mind. Whether you’re protecting your home or powering a large facility, our team is here to guide you every step of the way.
👉 Contact Synergy Standby Solutions today for a free consultation or generator sizing assessment.
