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Will Plug-In Solar Make My Meter Run Backwards?

A common hope is that plug-in solar will spin the meter backwards and erase the bill. It usually won't, and with some meters it can even count against you. Here's what actually happens.

By David Álvarez GonzálezUpdated 2 min read

In this guide
  1. What happens to the power, second by second
  2. What different meters do with exports
  3. Why exports aren't credited
  4. How to keep exports low
  5. FAQ

Short answer: usually not. Most US homes have smart meters that record power you take from the grid and power you send back separately, and plug-in solar laws exclude these kits from net metering. So exports don't reduce your bill. The savings come only from the power your home uses as it's produced, which is why sizing the kit to your daytime use matters.

What happens to the power, second by second

Your home's wiring sees the kit as one more source. At any moment:

  • Home uses more than the kit makes (say 600 W used, 400 W produced): the kit covers 400 W and the meter records only the 200 W you still draw. That's the saving.
  • Home uses less than the kit makes (say 150 W used, 600 W produced): 450 W flows out through the meter to the grid. Whether that counts for anything depends on the meter and the rules.

What different meters do with exports

MeterWhat happens to exported power
Smart meter, separate import/export registersRecorded as export; not credited unless you have net metering
Smart meter set to count absolute flowCan be counted as usage, so exports could increase your bill
Smart meter, net (bidirectional) modeSubtracted, but utilities normally only use this mode with an interconnection agreement
Old electromechanical dial meterMay slow or reverse, or may not register; utilities often replace them when they detect exports

About 73% of US residential meters were smart meters in 2022, according to the EIA, and the share keeps growing. Your utility can tell you how your meter is programmed.

Why exports aren't credited

Net metering, where exports offset your bill, comes with an interconnection agreement. The point of plug-in laws is to skip that agreement for small devices, and in exchange they exclude those devices from net metering. Utah's and Vermont's laws say so expressly, and Vermont adds that exported power isn't compensated. See how plug-in laws work.

Relying on an old meter to run backwards without an agreement may breach your utility's terms, and the utility can replace the meter at any time. Plan your savings without it.

How to keep exports low

  1. Size the kit to your base load. If your home rarely draws more than 300 to 400 W in the day, a 400 W kit wastes almost nothing. See which size you need.
  2. Shift loads to midday: dishwasher, laundry, dehumidifier, EV charging. See what a kit can power.
  3. Consider zero export: some kits add a sensor at the panel and throttle output so nothing leaves the home. CraftStrom's kits, for example, include an in-panel smart meter.
  4. Consider a battery only if you're away all day. See plug-in solar with a battery.
  5. Tell your utility what you installed, so a technician doesn't misread the exports. See do you need to tell your utility?

Frequently asked questions

Will my electric meter run backwards with balcony solar?

Usually not. Most US homes now have digital smart meters that record power taken from the grid and power sent to it separately. Plug-in solar laws generally exclude plug-in devices from net metering, so exported power isn't subtracted from your bill.

Can plug-in solar increase my electric bill?

It shouldn't, but some meters are configured to count any power flow as usage, in either direction. If your kit regularly exports and your meter is set up that way, exports could be billed. Size the kit to your daytime use and ask your utility how your meter records reverse flow.

Is it legal to run my meter backwards with a plug-in kit?

Getting credit for exports is net metering, which requires an interconnection agreement. Plug-in laws exempt you from that agreement precisely because plug-in devices don't get net metering. Deliberately using an old meter to offset your bill without an agreement may breach your service terms.

What is a zero-export setting?

Some kits pair the inverter with a sensor at your electrical panel or meter and reduce output so the home never sends power to the grid. It wastes a little potential output but avoids export questions entirely.

Update log

  • Guide published.

Sources and official texts

  1. U.S. EIA: How many smart meters are installed in the United States?
  2. Utah Legislature: HB 340 (2025), enrolled bill text (plug-in devices excluded from net metering)
  3. Vermont Legislature: Act 149 (S.202) as enacted (no compensation for exports)
  4. pv magazine USA: Maine's plug-in solar law takes effect in July (CraftStrom smart meter approach)

David Álvarez González

We track plug-in solar laws, product certifications and real-world savings across the US and the UK. Every guide links to the bill text, regulator or standard it relies on, and law pages carry a dated update log.

How we research and update our guides

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