One number on your electric bill matters for solar: the kilowatt-hours you used this month. Everything else on the page is either arithmetic built on that number or a fee solar cannot touch. Find the kWh, and the rest of the bill starts making sense.
Your utility would rather you look at the dollars, and most people do, because the dollars are the part that hurts. But a solar system gets sized from the energy your house actually uses, measured in kWh. Square footage does not size a system. The dollar total does not either, since two houses with identical totals can be using very different amounts of power. Usage is the ground truth, and it has been printed on every bill you have ever received.
Where the kWh number hides
Every utility lays its bill out differently, but the number is always there. Look for a line called kWh used, total usage, energy usage, or billed kWh, usually near the meter readings. On a Gulf Power style FPL Northwest bill it sits in the usage summary. Co-op bills around the panhandle use their own labels and sometimes tuck it into the meter reading table, where it shows up as three numbers: previous reading, current reading, and the difference between them. That difference is your month.
If the paper bill defeats you, log in to your utility's website. The online account almost always shows usage more clearly than paper does, and it usually keeps a year or more of history sitting right there.
Quick footing check. A kWh is a running total of energy used, the odometer reading rather than the speedometer. The full watts versus kilowatt-hours lesson is its own guide; here, kWh just means how much, added up over the month.
The chart worth more than the rest of the page
Most utilities print a small bar chart on the bill: twelve or thirteen months of usage, side by side. It is the single most useful thing on the page. One glance shows your summer peak, your winter low, and what an ordinary month looks like in between.
That chart is a year of your life in electricity. The tall bars are July and August with the AC grinding. The short ones are the mild months when the windows were open. Somebody sizing a system for you should be looking at that shape, because a system built for the tall bars behaves very differently than one built for the short ones. When anyone asks how big a system you need, the honest answer starts with this chart.
Your real rate is a division problem
Bills split the price of power into pieces. An energy charge, a fuel charge (sometimes called fuel cost recovery), taxes, franchise fees, storm surcharges. No single line item tells you what you actually pay for a kWh.
So skip the line items and divide. Take the total dollar amount of the bill and divide it by the kWh used. Say a bill totals $180 for 1,200 kWh; those are round example numbers, yours will differ. $180 divided by 1,200 is 15 cents per kWh. That is your blended rate, the all-in cost of one kWh at your house, fees and taxes included.
The blended rate matters because it is what a kWh of solar production is worth to you. Every kWh your panels make and your house uses is a kWh you did not buy at that rate. Fuel charges drift month to month, so run the division on two or three bills and take the middle.
What solar removes, and what it never removes
Solar attacks the usage side of the bill. Shrink the kWh you buy and the energy charge, the fuel charge, and the taxes riding on both shrink with it. On a bill dominated by usage, which describes most Florida homes in summer, that is most of the bill.
Here is the part the yard-sign sales pitch skips. Somewhere on your bill is a flat monthly amount, usually labeled customer charge, base charge, or service availability charge. That is the cost of being connected to the grid at all. You pay it if you use 2,000 kWh and you pay it if you use zero. Solar does not remove it. Batteries do not remove it. As long as the wire to the pole stays connected, that charge survives.
So when someone promises your bill will be zero, treat it as a sales line, because it is one. A well-sized system can take a real bite out of the energy portion. The connection fee stays, and an honest quote says so up front.
Summer and January are different houses
A Florida house does not use power evenly. An August bill with the AC running hard might show 2,200 kWh. January for the same house can come in under 1,000. Round examples again, but the gap is real, and it is why a single bill misleads in either direction.
Size from August alone and you buy a system that overproduces for most of the year. Size from January and the first summer eats you alive. The number that behaves is the yearly total. Twelve months of kWh, added up, smooths the seasons into one figure a system can actually be designed around.
That is the homework, and it takes ten minutes. Pull your last twelve bills, or open the online usage history, and add up the kWh. One number, the yearly total. Bring that to the system builder or bring it to us, and the sizing conversation starts on solid ground.
What Ape Solar would check first
Hand us a bill and here is where our eyes go. The usage history chart first, for the shape of the year. Then the twelve-month total, because that is the number the design hangs on. Then the blended rate, total divided by kWh, since that sets what each produced kWh is worth at your address. Last, the fixed charge, so nobody in the room is pretending the bill goes to zero. Four numbers, all on one page, and they tell us more than an hour of talking about your roof.
FAQ
Can solar actually get my bill to zero?
No, and be wary of anyone who says otherwise. The usage charges can drop a long way with a well-sized system. The fixed connection charge stays as long as you are tied to the grid, so the floor of your bill is that charge plus taxes, never zero.
My bill only shows a dollar amount. Where do I find the kWh?
Check the meter reading section for previous and current readings; the difference is your usage. If the printed bill truly hides it, your online account will have it, and the utility will hand over twelve months of usage history if you call and ask. They keep it for every meter they read.
Should I size my system off my biggest bill?
No. Size from the yearly total. Building to the August peak means overbuying for the other nine or ten months. Backup planning is a different conversation, where the loads you want to keep running matter more than the bill does, and it deserves its own numbers.
I just moved in and have no bill history. Now what?
Ask the utility for usage history at the address. Many will share the totals from before you moved in, and the house's habits matter more than whose name was on the account. Failing that, a few months of your own bills gets the shape close enough to start.
Ready when you are: send us your power bill and what you want to keep running. Reading them is what we do all day.