Do Whole-Home Generators Work with Solar Systems in Missouri?
Combining solar power with a backup generator can offer true energy independence—especially in Missouri, where weather can flip from heatwaves to ice storms in a matter of weeks. Many homeowners in towns like Union, Pacific, and Wildwood are exploring how to create resilient energy systems that protect their homes from grid outages while saving money on utility bills.
One of the biggest questions we get at Cain Electric is: Can I run a generator with my solar panels? The answer is yes—but there are important factors to get right to avoid damaging your equipment or wasting money.
This article explains how whole-home generators and solar systems can work together, what equipment you need, and how to make it all run safely and efficiently.
Why Combine Solar and Generators in Missouri?
Missouri homeowners are increasingly investing in energy redundancy. Here's why combining both systems makes sense:
- Frequent Power Outages: Ice storms, high winds, and lightning strikes often knock out power in places like Washington, Villa Ridge, and rural parts of Franklin County.
- Grid Instability: Missouri utilities are modernizing slowly, and some areas experience brownouts or surges.
- Net Metering Limits: Solar alone doesn’t always provide backup power unless paired with batteries or generators.
- Cost Savings: Use solar for daily power and the generator only during emergencies.
Solar Alone Doesn’t Keep the Lights On
Many homeowners assume their solar panels will keep the house powered during an outage. Unfortunately, most grid-tied solar systems shut down when the grid goes down. This is a safety measure to protect utility workers.
To Stay Powered During an Outage, You Need:
- Battery Storage OR
- A Backup Generator OR
- Both (ideal for most Missouri homes)
How Solar and Generators Can Work Together
There are two main ways to integrate a generator into your solar setup:
1. Hybrid Solar + Generator (With Battery Bank)
This setup offers the highest level of resilience. The battery bank supplies power when the sun goes down, and the generator only kicks in when the battery gets low.
How It Works:
- Solar charges the batteries.
- The home runs off solar/battery power.
- When battery levels drop, the generator starts automatically.
| Component | Role |
|---|---|
| Solar Panels | Primary power during sunlight hours |
| Battery Bank | Stores excess solar for nighttime use |
| Generator | Emergency backup when battery runs low |
| Automatic Transfer Switch | Safely transitions between sources |
2. Grid-Tied Solar + Generator (No Batteries)
If you're not ready to invest in batteries, you can still add a generator for backup.
How It Works:
- Solar offsets your utility bill while grid power is active.
- Generator powers essential loads during outages.
- System uses an automatic transfer switch to switch power sources.
Important Note:
- You cannot run solar and generator power simultaneously without special equipment. This is where professional design and installation matters.
Generator Types That Work Best with Solar
| Generator Type | Ideal For | Notes |
|---|---|---|
| Standby (Whole-Home) | Full backup power | Most seamless and reliable |
| Portable Generator | Essential circuits only | Lower cost, requires manual connection |
| Inverter Generator | Quiet and efficient use cases | Ideal for small systems or critical circuits |
Cain Electric recommends standby generators for Missouri homeowners serious about backup power. We size and configure them based on your home’s electrical needs and existing solar array.
Equipment You’ll Need to Integrate Systems
To safely connect a solar system and generator, you'll need more than just plugs and wires. Here are the essentials:
| Equipment | Purpose |
|---|---|
| Automatic Transfer Switch (ATS) | Detects outages and switches to generator power |
| Critical Load Panel | Separates essential circuits for generator or battery backup |
| Inverter (Bi-directional or Hybrid) | Coordinates solar, battery, and generator input/output |
| Generator Interlock Kit | (Optional) Prevents backfeed into the grid if ATS isn’t installed |
All installations in Missouri must comply with the National Electrical Code (NEC) and local permitting requirements. Cain Electric handles all inspections and ensures your system is safe and legal.
Challenges to Watch For
| Challenge | Solution |
|---|---|
| Power Source Conflict | Use smart inverter + ATS to control flow |
| Panel Overload | Perform load analysis to size generator properly |
| Improper Transfer Timing | Use high-quality ATS with short switch lag |
| Solar Inverter Incompatibility | Choose solar components designed for hybrid use |
A licensed electrician should handle all interconnections—mistakes here can damage your system or void your warranties.
Common Missouri Use Cases
- Union Homeowner with 10 kW Solar + Battery: Adds 22 kW Generac generator for multi-day outages.
- Pacific Resident on a Budget: Grid-tied solar + portable generator for fridge, lights, and heat.
- Washington Family with High Usage: Full integration of solar, Tesla Powerwall, and standby generator.
Is It Worth the Investment?
For many Missouri homeowners, the answer is yes—especially those who:
- Experience regular outages
- Work from home
- Have refrigerated medications or medical equipment
- Want peace of mind during storms or emergencies
Estimated Costs:
| Setup Type | Approximate Installed Cost |
|---|---|
| Grid-Tied Solar Only | $20,000–$30,000 |
| Add Standby Generator | $7,000–$12,000 |
| Add Batteries (Optional) | $12,000–$20,000+ |
| Total Hybrid System | $30,000–$60,000+ |
Incentives like the 30% Federal Solar Tax Credit can reduce the cost of your solar system. Generators typically do not qualify unless integrated into an off-grid or battery-backed design.
Next Steps: Get a Custom System Designed
Cain Electric designs, installs, and services hybrid solar + generator systems throughout Franklin, Jefferson, and St. Louis Counties. If you’re in Missouri and want energy security year-round, we can help you:
- Size your system for your home’s needs
- Recommend compatible components
- Install and inspect everything for safety and compliance
Ready to build a system that works in every season? Contact Cain Electric today for a consultation.
