Net metering is how your power company keeps track of the power your solar sends out and the power your home pulls in. The examples below describe southern Nevada customers on the power company's NMR-405 plan (your net metering rate; your bill shows it as a code). Boulder City operates its own utility and has different credit rules, explained below. Older plans and other utilities may work differently.
Day and night
Without a battery, your home uses solar power as it is produced, and excess can flow to the grid. With a battery, some energy may be stored for later use; the flows depend on the system's settings. The diagrams below show a home without a battery.
In this example without a battery, the home uses available solar power and the excess goes to the grid. The power company counts that export as kWh received. A kWh (kilowatt-hour) is the unit your power bill uses to measure electricity.
Without a battery, the home draws from the grid after sundown. The power company counts that import as kWh delivered. A battery may also supply the home at night.
How the month adds up
For southern Nevada customers on NMR-405, net metering is settled over the monthly billing period. Your power company adds up the kWh it delivered to your home and the kWh it received from your system, then nets them.
- If your home drew more than it sent, each kWh you sent offsets one kWh you drew for the net energy calculation. Other charges still apply under your rate plan.
- If your solar sent more than your home drew, the extra becomes a credit on your bill.
For NMR-405 customers, the extra is credited at a percentage of the applicable retail energy rate, excluding certain charges. New qualifying systems of 25 kW or less enter tier 4 at 75%. Earlier NMR-405 tiers receive 95%, 88% or 81%; the assigned tier generally applies at that location for 20 years. Older plans, including NMR-A, have different rules. Time-of-use plans have additional details, so check your rate schedule.
Boulder City utility customers: The city's net metering policy credits monthly excess at its average wholesale energy cost. Credits can be carried forward, but expire 12 months after they are issued. They cannot be cashed out, transferred, or used for other charges such as the monthly customer charge.
How to read your bill
Every bill is laid out a little differently. Here's an illustrative southern Nevada NMR-405 example for a spring month; the numbers, including the basic service charge, are made up. Your actual charges and bill may differ.
- Basic service charge
- $18.00
- Energy delivered to youdrawn from the grid
- 410 kWh
- Energy received from yousent to the grid
- 550 kWh
- Net energy this monthyou sent 140 kWh more than you drew
- 140 kWh excess
- Excess energy credit140 kWh × your credit rate
- carried forward
- Basic service charge. A monthly charge that applies regardless of how much electricity you use or send. The $18 shown here is illustrative; check your rate schedule for the actual charge.
- Delivered. Power your home pulled from the grid: nights, evenings and any time it needed more than the panels were making.
- Received. Power exported to the grid. This is not necessarily everything your panels made; a battery can also affect the flow.
- Net. Delivered minus received. Here the home sent more than it drew, so there's an excess.
- Credit. The excess, valued at your credit rate, is applied to a later bill.
In a summer month the same home might draw 1,100 kWh and send 700. Then there's no excess: the energy portion is based on the 400 kWh difference, subject to the applicable rate and available credits. The basic service charge and public policy charges assessed on delivered energy also apply.
Some bills show grid exchanges without showing total panel production. Check your monitoring app for production. Without a battery or other generation, home use can be estimated from production minus exports plus imports; storage, charging losses and other equipment make the calculation more complex.
Why your bill usually isn't $0
The fixed charge is always there
The basic service charge comes every month, and credits can't be used to pay it or other fixed fees. Under the power company's NMR-405 plan, public policy charges on delivered energy also apply.
Your home uses power at night
Panels make nothing after dark. Your home may draw from the grid or a battery, if you have one. If your home draws more over the month than it sends, charges apply to the difference under your plan.
Credits can be worth less than retail
For new qualifying southern Nevada NMR-405 systems, excess is credited at 75% of the applicable retail energy rate. Boulder City and older rate plans use different rules.
None of these mean anything is wrong with your system. A bill that jumps from one year to the next is worth a look, though. Our guide to what to check when your bill changes walks through it.
Cloudy days
Southern Nevada gets a lot of sun, but clouds, monsoon storms, dust and short winter days all lower what your panels make. On a heavy overcast day they may make only a small share of a clear day's power. That's normal, and they pick right back up when the sky clears.
For southern Nevada NMR-405 customers, monthly netting means a few cloudy days are part of that month's total. A cloudy stretch or a winter month may have a larger effect.
What isn't normal: low production on a clear day, a day with no production at all, or a monitoring app that stopped updating. Summer heat lowers output a little too. Here's how Vegas heat affects production.
What happens to credits
For southern Nevada NMR-405 customers:
- A credit left on one bill rolls over to the next, and it can keep carrying forward.
- Credits aren't paid out in cash, including if you move, or if the system is removed or transferred.
- A replacement at the same home may qualify to keep an existing rate. The power company reviews replacement applications, so confirm eligibility before making changes.
Last checked
We last checked this page on against the power company's NMR-405 information, its interconnection handbook (interconnection is the power company's OK to connect your system), and Boulder City's policy. The credit tiers are also listed on the Public Utilities Commission of Nevada's net metering page. Northern Nevada has different rules for new systems.
Rules and rates can change. Your own bill has the exact numbers for your home. For questions about your account or rate plan, contact your power company.