⚡️ Do You Need an Electrical Panel Upgrade? Here’s How to Tell
- Dale Rolph
- May 16
- 4 min read
Upgrading to solar or planning to install a Level 2 EV charger? Your electrical panel might be the hidden dealbreaker you didn’t know you had to check.
Whether you're trying to go green, charge your electric vehicle faster, or prep your home for future tech, your panel needs to keep up. This post will walk you through everything you need to know—from how to spot red flags to understanding why a panel upgrade is one of the smartest investments you can make.
🔍 What Is an Electrical Panel?
Your main electrical panel—often called a breaker box—is the control center for all the electricity in your home. It:
Receives electricity from the utility
Distributes power to all your circuits (appliances, lights, HVAC, etc.)
Protects your home using circuit breakers that shut off power if something goes wrong
Most homes have a panel rated for 100 amps, 125 amps, 150 amps, or 200 amps. Think of this number as the panel’s "speed limit"—go too far over, and you risk tripping breakers or even causing electrical fires.
🧠 How to Find Your Panel Rating
Step outside or into your garage and find the metal door labeled Main Electrical Panel. Inside, look for:
The words “Main Breaker”
A number next to it: 100, 125, 150, or 200
That number is your panel amperage.
📸 Tip: Take a picture of this label. You can show it to an electrician or send it when chatting with Ai Dale through the website.
🆘 If Your Panel Says 100A
A 100-amp panel is usually not enough for modern energy needs. You’ll almost certainly need an upgrade if you're adding:
A Level 2 EV charger
A home battery
A full solar system
Electric appliances (like dryers or heat pumps)
Most utilities and local codes won’t allow solar or battery systems to connect to 100A panels without major workarounds. It’s not just about having enough power—it’s about doing it safely and code-compliantly.
⚖️ What If My Panel Says 125A or 150A?
This is where it gets trickier.
A 125A panel is better than 100A, but still might not meet the needs of solar + battery + EV charging. It may also limit how much solar you’re allowed to install under the NEC 120% rule.
A 150A panel is closer to modern standards, and you might just barely get approved depending on your home’s current load and available breaker slots.
⚠️ Important: These panels require a load calculation to determine whether an upgrade is necessary. More on that below.
🚩 Warning: Unsafe Panel Brands
Some electrical panels aren’t just outdated—they’re dangerous. These brands are known to fail, catch fire, or not trip when they should.
🔥 Federal Pacific Electric (FPE) / Stab-Lok
Extremely high failure rate (60–70%)
Breakers don’t trip when they should
Fire hazard
Installed in homes from 1950s to 1980s
⚠️ Zinsco (Sylvania Zinsco)
Breakers melt to the bus bar
Known for overheating and arcing
Found in homes built 1960s–70s
Bright-colored breaker handles
🧲 Pushmatic
Outdated push-button breakers
Often get stuck or become unresponsive
No longer manufactured
👎 Challenger
Found in homes built 1980s–90s
Breakers prone to overheating
Not officially recalled but frequently replaced
If you have one of these, it’s strongly advised to replace it ASAP—even if you’re not going solar yet.
📏 Load Calculations: The Real Way to Know
If you're unsure whether your current panel can handle upgrades, the answer lies in a load calculation. This is how electricians determine how much power your home uses vs. how much your panel can safely provide.
Here's a simplified version:
Step 1: Add Up Your Big Appliances
Electric Oven: ~5,000W
Dryer: ~4,000W
HVAC: 3,000–10,000W
Water Heater: ~4,500W
Level 2 EV Charger: ~9,600W
Step 2: Convert Watts to Amps
Divide watts by 240V (typical U.S. home voltage) Example: 9,600W ÷ 240V = 40 amps
Step 3: Add Up the Total Load
Then compare it to your panel’s rating (e.g., 100A, 125A, 200A). If you're using more than 80% of the panel, it's time to upgrade.
🧮 The 120% Rule
Under NEC 705.12(D) (a.k.a. the 120% rule), you can’t backfeed more than 20% of your panel’s bus rating with solar. So if you have a 125A panel:
125A × 120% = 150A total
Subtract your 125A main breaker = 25A available for solar
That’s roughly 5,750W of solar (23A × 250V)
Want to install more than that? You’ll need a line-side tap, main breaker reduction, or—you guessed it—panel upgrade.
🔋 Why Upgrading Now Saves You Later
Even if your current panel technically works, upgrading now has long-term benefits:
🌱 Future-Proof Your Home
Add a second EV
Install batteries later
Switch to electric appliances
Support smart panels & automation
🧠 Enable Smart Home Technology
Devices like Span, Leviton, and Sense give you control over circuits via app
Monitor energy usage, automate loads, and even shut off circuits remotely
💰 Boost Home Value
A modern panel makes your home more appealing to buyers
It’s a visible sign that the home is energy-ready
🛠 Avoid Rework & Extra Permits
Doing upgrades in stages means more permits, inspections, and labor costs. Bundling it together can save you thousands.
🧾 Final Checklist for Homeowners
✅ What’s the amperage listed on your main breaker?
✅ Are you planning to add solar, batteries, or an EV charger?
✅ Do you have outdated or dangerous panel brands?
✅ Have you done a load calculation or consulted an electrician?
✅ Are you looking to make your home smart/automated?
✅ Do you want to avoid repeat construction and extra costs later?
👷 Need Help?
At Renewable Innovations, we help homeowners like you evaluate your panel, size your solar + battery system, and upgrade if needed.
We’re here to:
🔌 Guide you through panel inspections
⚡️ Size your system for now and the future
🔋 Help you qualify for incentives
📸 Provide before/after documentation for peace of mind
📸 Stay tuned—we’re adding real-world photo examples soon so you can compare your setup visually.
Or better yet, schedule a free consult and let us take a look for you. Energy independence starts at the panel—let’s make sure yours is ready. 🔧
Comments