Question 1

How do I know if my electrical panel can handle more?

Accepted Answer

It's decided by a load calculation, not by counting breaker slots. The NEC (Article 220) totals your demand (general lighting, appliances, the larger of heating or cooling, and continuous loads like an EV charger at 125%), applying demand factors because everything rarely runs at once. If the calculated demand stays comfortably under your service rating, you have room.

Question 2

Why don't you just add up all the wattages?

Accepted Answer

Because that overstates the load. Your range, dryer, water heater, and AC almost never run at full power simultaneously, so the NEC applies demand factors (for example, general lighting load beyond the first 3,000 VA counts at 35%). Adding raw nameplate watts can make an adequate panel look overloaded.

Question 3

Do I need a 200-amp panel for an EV charger?

Accepted Answer

Not always. A 200A service usually has room; many 100A and 150A panels can also add a charger, especially with gas appliances or a lower-amperage or load-managed charger. Run your numbers here, then have an electrician confirm with a stamped load calc: the EV charger counts as a continuous load at 125%.

Question 4

Is this an official load calculation?

Accepted Answer

No, it's a planning estimate using the NEC standard method. The real decision needs a licensed electrician's stamped calculation and sign-off from your local Authority Having Jurisdiction (AHJ), and a service upgrade also requires utility coordination. Use this to understand your situation before you call.

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