What Is Solar Export? Where Your Surplus Power Goes

What counts as an export

Picture a sunny noon. Your panels make 5 kW. Your fridge, router and air conditioner use 2 kW. The house takes the 2 kW first. The other 3 kW has nowhere to go inside, so it flows out through the meter. That 3 kW, kept up for an hour, is 3 kWh of export.

Once outside, the power feeds your neighbours on the same local line. DOE describes this as surplus from distributed solar serving nearby load ⁹. The utility does not store it for you. It sells it on and records what you sent.

What the utility pays for that kWh is a separate question, covered on our export compensation page. This page is about the kWh itself: how it is made, measured, shown and limited.

Sources: [9]

The path of one exported kWh

1. Panels make DC power → the inverter turns it into AC
2. AC power reaches your electrical panel → home loads take what they need
3. Leftover power passes the meter → the “received” channel counts it
4. Power flows onto the street line → a neighbour’s home uses it

How the meter counts exports

A normal meter only counts power coming in. A solar home needs a bi-directional meter, one that counts flow both ways. Georgia Power programs a customer’s meter “for bi-directional service” only after the system passes testing and gets permission to operate ¹.

The meter keeps two running totals, often called channels or registers. Duke Energy Kentucky’s net metering filings call them “delivered” (from the utility to you) and “received” (from you to the utility) ³. Santee Cooper’s DG-25 rider describes the same two measurements: energy the utility delivers and energy the customer-generator delivers back ².

Smart meters also store these totals in short time blocks. That is what lets a utility net by the hour, or by the half hour, instead of once a month.

Sources: [3] [2] [1]

Netting intervals: why the same day can show different exports

Example: one afternoon, three ways to count

An illustration with round numbers we chose. In one hour the panels make 4 kWh. The home uses 3 kWh, but not evenly: for 30 minutes it uses less than the panels make, then the oven comes on.

Same panels, same home, same hour. Instant netting records 50% more export and also bills an import. That is why the netting interval in your tariff matters as much as the export rate. The net billing calculator lets you test your own mix.

Where exports show up on your bill

• Received kWh. The total sent to the utility this billing period. Duke Energy Kentucky shows “delivered” and “received” kWh ³.
• Net kWh. Delivered minus received, if your tariff nets in kWh.
• A credit in dollars. Under Duke Energy Kentucky’s Net Metering II rider, from 1 Jan 2025, exported kWh are turned into dollars at an avoided-cost credit rate ³.
• A carry-forward balance. Santee Cooper carries a monthly net credit under $50 to the next bill and pays $50 or more by check ².
• A rider line. The name of the solar tariff you are on. Our first bill after solar guide walks through a full bill.

How much do homes actually export?

Real figures are rare, but one utility files them every year. Duke Energy Kentucky reported 1,032 residential net metering customers as of 31 Aug 2025 ³. Over September 2024 to August 2025 it delivered 10,889,325 kWh to them and received 4,347,810 kWh back ³.

That works out to roughly 40 kWh received for every 100 kWh delivered, and about 4,200 kWh of export per home for the year (our division of Duke’s totals). It is one Kentucky utility, not a national rule. Your share depends on system size, roof and how much power you use in the daytime.

Sources: [3]

Exporting: what you gain and what you give up

Export limits and zero-export systems

A utility can cap exports or ban them. Georgia Power offers “Energy Offset Only” (EOO): the system “cannot push energy back onto the Electric System” and is not paid for surplus ¹.

Georgia Power may require equipment to stop exports, and it puts a system on EOO by default if the customer has not picked a program ¹.

How do you stop power flowing out? New Mexico’s interconnection rule lists the accepted methods plainly ⁵. A reverse-power relay trips if power starts to flow out.

A minimum-import relay trips if imports drop too low. A power control system certified to UL 1741, with a response time of no more than 30 seconds, can hold exports at zero or at a set cap ⁵.

A system can also simply be small enough, no more than half the home’s verified minimum load ⁵.

These are New Mexico’s rules, shown as a clear example. Your own utility’s list may differ. In Georgia, a battery that can run in backup mode needs Georgia Power’s DB 18-23 non-export form ¹.

Sources: [1] [5]

What exports do to cost and value

We do not give system prices here; see our solar cost guide. What exports change is the value side.

Every kWh you export instead of using yourself is worth the export credit, not the retail price you avoid. The bigger the gap between those two, the more a high export share drags on payback. A battery or moving loads into sunny hours can shift kWh from export to self-use.

Export controls add hardware and design work. A certified power control system or relay is part of the quote, not an extra you can skip if your utility requires it. Ask the installer to list it as its own line.

How you get set up to export

The usual order, based on Georgia Power’s published residential process ¹. Your utility’s steps may differ.

1. Choose an export program or a no-export option with your installer.
2. The installer applies to the utility with diagrams and equipment specs. Inverters must show UL 1741 SB and IEEE 1547-2018 listing for Georgia Power ¹.
3. The utility reviews the request and may set an export cap for your line.
4. You sign the interconnection agreement that names your export terms.
5. A licensed installer builds the system, and the local inspector checks it.
6. The utility tests the system, reprograms or swaps the meter for two-way service, and grants permission to operate.

Checking your exports over time

• Compare the “received” kWh on each bill with the same month last year. A sharp drop with similar weather can mean a fault.
• If your monitoring app has a consumption meter, compare its export figure with the bill.
• After adding a big load, such as an EV, expect exports to fall. That is normal, not a fault.
• Keep the inverter’s grid settings as the utility approved them. Changing an export cap needs the utility’s say.

Warning signs and when to call a pro

• Your bill shows zero received kWh months after permission to operate. The meter may not be set for two-way service. Call the utility.
• The system exports before approval. Georgia Power says it detects this through reverse energy flow alerts and may disconnect service ¹.
• A zero-export system shows exports on the bill. The control or relay may have failed; call the installer.
• The inverter keeps cutting output at midday with high-voltage alarms. Your line may be crowded; ask the utility and installer.
• Any heat, buzzing or burning smell near the meter or inverter. Call a licensed electrician.

Safety rule

Who sets export rules

Technical rules (national). IEEE 1547-2018 sets how inverters connect and respond to grid voltage and frequency ⁸. It is why an inverter may cut back exports when line voltage runs high.

Metering and netting rules (state or utility). These come from tariffs approved by a state commission or, for public power, the utility’s board.

Examples: Georgia Power’s RNR tariffs, under the Georgia PSC (order of 2 Mar 2021 in Dockets 4822 and 16573) ⁴; Santee Cooper’s DG-25, set by its board ²; and Dominion Energy Virginia’s NEM 2.0, approved by the Virginia SCC in Case PUR-2025-00079 (Order on Clarification 20 May 2026) ⁷.

Export-limiting rules (state). Some states write the accepted control methods into rule, such as New Mexico in 17.9.568.12 NMAC ⁵. Others leave it to each utility’s manual.

No national rule says how exports are netted or paid. Always read your own utility’s tariff.

Sources: [8] [4] [7] [5]

Solar export vs related terms

Common misconceptions

Myth My app’s production number is what I exported.

Reality Production includes everything your home used first. Only the leftover is exported.

Myth The grid stores my exports for me.

Reality Exports are used right away by nearby homes ⁹. Any “bank” is a billing record, not stored power.

Myth Every utility counts exports the same way.

Reality Netting runs from instant (Georgia Power RNR-Instantaneous) to hourly (Santee Cooper DG-25) to yearly (Virginia).

Myth A zero-export system needs no utility approval.

Reality Georgia Power still requires an application and an Energy Offset Only agreement ¹.

Exports in South Carolina, Georgia and Virginia

When exports matter to you

• Your utility pays far less for exports than retail. Size the system closer to your daytime use, or plan a battery.
• Your tariff nets instantly or hourly. Expect more exports than a monthly-netting neighbour with the same panels.
• Your utility offers no paid export, or your line is full. Ask about a zero-export or capped design.
• You want to check a quote. Ask the installer what share of output they assumed would be exported, and why.
• Next step: compare installers through Get Solar Options.

Related terms

Export Compensation

Export compensation is the credit or payment a utility gives for electricity a solar system sends to the grid, the excess generation the home does not use at that moment.

Net Metering

Net metering is a utility billing arrangement in which the electricity your solar system sends to the grid is subtracted from the electricity you take from it, so you are billed only for the net amount over a set period.

Net Billing

Net billing is a solar compensation method in which the utility bills every kWh you import at its retail rate and credits every kWh you export at a separate, usually lower, export rate, with the two settled in dollars rather than netted in kilowatt-hours.

Solar Production

Solar production is the amount of electricity a solar system generates over a period, measured in kilowatt-hours (kWh) and usually quoted per year.

Grid-Tied Solar

Grid-tied solar is a solar system connected to the utility grid through your home’s electrical panel and meter, so the house uses solar power first, draws from the grid when solar falls short, and can send surplus back to the utility.

Solar Inverter

A solar inverter is the device that converts the direct current (DC) made by solar panels into the alternating current (AC) your home and the utility grid run on.

Distributed Generation

Distributed generation (DG) is electricity made by small power sources close to where it is used, such as rooftop solar on a home, instead of by a large power plant far away on the transmission grid.

Solar Battery

A solar battery is a rechargeable battery, usually lithium-ion, that stores electricity your solar panels make but your home does not use straight away, so you can use it after dark, during a power cut, or when grid power costs most.