It is a Tuesday afternoon in June. Nobody is home. The AC is idling, the fridge cycles on and off, and the array on the roof is making 5kW in full sun. The house is only using about 600W of it. So where does the other 4.4kW go?
It goes out the same wire it normally comes in on. Your meter watches it leave and counts it. That counting is net metering, and it is the difference between a solar array that pays you back and one that just spins for the birds.
The meter is the whole trick
An old electric meter only knows one direction. Power comes from the utility, the dial turns forward, you get a bill. Simple.
A solar house gets a different meter, a bidirectional one. It keeps two running totals. One for the power you pull from the grid when your panels are not keeping up, like at night. One for the power you push back when your panels make more than you need, like that Tuesday afternoon. At the end of the month the utility looks at both numbers.
Here is the part people miss. You are not selling all your solar power to the utility. You use most of it yourself, right there in the house, the second your panels make it. Net metering only deals with the leftovers, the kWh you made but did not use. Those are the ones that flow backward and get logged.
What a month looks like
Round numbers, just to show the shape of it. Say your house uses 1,100 kWh in a month. Your array makes 900 kWh that same month.
Of those 900, say 500 get used the moment they are made. That power never touches the meter. It runs your AC and your fridge directly, and it shaves your bill the most, because every one of those kWh is a kWh you did not buy.
The other 400 get made when the house does not need them, so they flow to the grid. The meter logs 400 kWh out. Meanwhile the house still pulled 600 kWh from the grid at night and on cloudy mornings. The meter logs 600 kWh in.
The utility nets the two. 600 in, 400 out, and you get billed for the difference: 200 kWh. You used 1,100, you paid for 200. The array covered the rest.
The credit, and the catch
When you push more onto the grid in a month than you pull, you do not get a check that month. You build a credit, measured in kWh, and it rolls forward to the next month. A sunny April can carry you into a cloudier May.
The catch shows up once a year. Most Florida utilities run an annual true-up. If you finish the year with leftover credits, the utility buys them back, but not at the retail rate you would have paid for them. They pay the avoided-cost rate, which is the wholesale price, and it is a lot lower than retail. So the goal is to size an array that covers your usage, give or take, rather than one that dumps a huge surplus onto the grid for pennies.
As of June 2026, Florida's investor-owned utilities still credit your monthly net excess at the full retail rate before that annual true-up. That rule has been fought over in Tallahassee before, and it can change, so check your own utility's net metering tariff before you bank on a number. The mechanism is the same everywhere. The exact cents per kWh are not.
Why this changes how you build
Two lessons fall out of the meter math.
First, the kWh you use yourself are worth more than the kWh you export. That is the argument for a battery. Store your midday surplus, run on it at 7pm when the house wakes up, and you are spending your own cheap solar instead of buying grid power at retail and exporting the extra for wholesale. The battery turns those 400 export kWh into 400 self-used kWh.
Second, bigger is not automatically better. An array sized way past your usage spends most of its surplus at the avoided-cost rate, which is a slow way to earn your money back. Sizing it close to your real annual usage is usually the sharper buy.
Net metering is the quiet machinery that makes a grid-tied solar house work. The meter counts honestly in both directions, you pay for the net, and the credits carry you through the dark months. Watching the dial run backward on a June afternoon is the fun part. The math underneath it is what actually lands on the bill.
Want to see the numbers for your roof and your usage? The system builder sizes an array to your real bill and shows you the export math before you buy. Or start at the shop if you already know what you need.