Why solar doesn't zero out your electric bill
Short answer: solar only offsets the generation part of your bill. You keep paying delivery and fixed fees to the utility no matter how much solar you produce — so the bill never quite hits zero.
Your bill has two very different halves
Almost every electric bill splits into two parts that get lumped into one number:
- Generation (supply): the cost of actually producing the electricity — the energy itself.
- Delivery (distribution) + fixed fees: the cost of moving that electricity over the grid to your house, plus flat monthly "customer" or "basic service" charges you owe just for being connected.
When an installer says solar will "eliminate your bill," they're really talking about the first half. Rooftop solar reduces how much energy you buy — so it shrinks generation charges. It does almost nothing to the second half.
Solar offsets generation, not delivery
Every kWh your panels produce is a kWh you don't buy at the generation rate. Overproduce, and many utilities credit the excess back. Great — but those credits and offsets almost always apply to generation only. The delivery charge is billed on the electricity you pull from the grid, and the fixed monthly fee is owed regardless of usage. Neither goes away.
You can cover 100% of your energy with solar and still get a bill — because you never stopped using the grid.
How big is that floor?
Bigger than most people expect. It varies by utility and rate plan, but the non-generation portion is frequently a large slice of the total.
That's a real number from one household's data (mine), not a marketing figure — and it's exactly why a system that "covers your usage" can still leave a meaningful monthly bill. Your split will differ; the point is to actually look.
Why this matters for payback
If you assume solar zeroes your bill, you'll overestimate savings and underestimate payback. The honest math is: solar erases (most of) the generation charges, and you keep paying delivery + fixed fees. A realistic ROI estimate has to model both — which is the whole reason this tool exists.
How to see your own split
Pull up a recent electric bill and look for separate "generation/supply" and "delivery/distribution" lines, plus any flat "customer charge." Then:
- Estimate mode lets you enter your generation rate, delivery rate, and fixed fee separately, so the projection reflects the delivery floor.
- Analyze mode imports your actual bills and charts the delivery-vs-generation split month by month — so you can see your real floor.
Find your delivery-vs-generation split
Drop in your bills or enter your rates — see exactly how much of your bill solar can (and can't) touch.
Run the Numbers →FAQ
Why is my electric bill still high after getting solar?
Solar only offsets the generation (energy) portion. You still pay delivery/distribution charges and fixed monthly fees, which solar can't reduce — so for many homes the bill never reaches zero.
Does net metering cover delivery charges?
Usually not. Most net-metering agreements credit exported solar against generation only, not delivery or distribution. You can export plenty of solar and still owe delivery and fixed charges. See net metering, explained.
What is a delivery charge on an electric bill?
It's what the utility charges to move electricity over the grid to your home, separate from generating it — typically a per-kWh charge plus fixed monthly fees. Solar does not offset it.