Adding panels changes your net metering rate

Adding panels to a solar system you already have can move you to the net metering rate that is open today, which is Tier 4 at 75 percent. Repairing or replacing what broke usually does not. Adding a battery with no new panels does not. If your original application went in before June 2020, the difference is money on every bill for the rest of your 20 years.

If your system went in after June 2020, you are already on Tier 4 and the rate question does not apply to you. The sizing limits further down still do.

Three jobs, three different answers

NV Energy's Net Metering and Energy Storage Interconnection Handbook, revision 7 dated October 16 2025, has a short section called System Expansions / System Replacements. It sets the rules in three sentences.

Two words in the last row matter. "May allow" is not "will". A replacement keeps your closed rate only if NV Energy's engineers decide, on your application, that it can. The handbook's section on system additions ends with the same advice, more plainly: "Ask before you add!"

The law protects replacement. It says nothing about making the system bigger.

NRS 704.773 subsection 8 is your 20 year right. It requires the Commission and the utility to let you continue net metering at the location where the system was originally installed for 20 years, and it says continuing includes two things: keeping your tier percentage, and "replacing the originally installed net metering system, as needed, at any time before 20 years after the date of the installation of the originally installed net metering system."

Replacement is written into the statute. Expansion is not mentioned there at all. Neither the statute nor the handbook says what happens to the years left on your clock when an expansion moves you to a new rate. We will not guess that in your favour. Get it from NV Energy in writing before anything is designed.

Which rate you are on now

Your tier was set by a date, not by your hardware. NRS 704.7732 subsection 5 says you are treated as accepting the utility's offer on the day you submit a complete application. The Public Utilities Commission of Nevada publishes when each tier opened and closed.

Older systems may be on NMR-G or NMR-A, both of which the handbook lists among the closed rates a replacement may keep. NV Energy's October 1 2026 net metering insert shows NMR-G as "Banking": exported kilowatt hours banked rather than paid at a percentage. If you are on either of those, the stakes of an expansion are different and larger, so ask before you do anything.

The rate is printed on your bill. How to read your NV Energy bill once you have solar shows where.

What the move costs, in cents

NV Energy's NMR-405 page says the credit applies to the exported energy that remains after monthly netting, at a percentage of the retail volumetric rate, which it defines as the consumption rate plus the DEAA component. The October 1 2026 net metering insert prints the result for each tier on Schedule RS:

The gap only applies to excess: what is left after the whole month has been netted. A kilowatt hour you export at noon and use back at eight the same month is settled against your usage and never meets the percentage. Net metering in Nevada explains why.

So the honest arithmetic uses your own bills. Add up the excess kilowatt hours across your last twelve statements and multiply by the gap. Our worked example, on the October 1 2026 figures:

• A Tier 1 house with 1,500 excess kWh a year: 1,500 × $0.02226 = $33.39 a year.
• A Tier 2 house with the same excess: 1,500 × $0.01447 = $21.71 a year.
• A Tier 3 house with the same excess: 1,500 × $0.00668 = $10.02 a year.

Two things make it bigger than that. The new panels are there to make more power, so your excess grows, and all of it is credited at the lower rate. And the rate underneath moves every time NV Energy's rates reset. If your bills show almost no excess, the tier move is small. If they show a large surplus every spring and autumn, it is real money for every remaining year.

Before you buy panels to fix something else

Many people who want more panels have a system that is making less than it used to. A failed inverter, a dead optimiser, a tripped breaker or a string left disconnected after a roof repair looks exactly like an array that is too small. Fixing that is a repair, not an expansion, and it does not touch your rate the way new panels would.

Check that first. Is my solar system working is the check we would run, and if the company that installed it has closed, what to do when your installer goes out of business covers who can still help.

If the house really does need more

The handbook limits how big the expanded system may be.

• A net metering system "must be sized to meet no greater than one hundred percent of a customer's annual electricity needs." The ceiling comes from "the highest energy usage that occurred in 12 consecutive months out of the last 24 months."
• If your loads have changed and the bills have not caught up, the handbook allows an energy audit report instead, by an auditor with an active licence from the Nevada Real Estate Division, following NRS 645D.300.
• An expansion is a new application. The handbook lists the southern Nevada initial review fee at $189 per application, and the application is cancelled if the fee is not received within 30 days of submission.

There is one kind of expansion that leaves your rate alone. A battery adds no renewable capacity, so by the handbook's own sentence it changes nothing about your percentage. Adding a battery to the solar you already have and why the 6 to 9 pm window matters work through whether that is worth it for you.

If you are buying a house on an old tier, the same rules apply to you from the day you close. Buying a Las Vegas house that already has solar covers that side.

Five questions to ask before anyone adds a panel

1. Which net metering rate am I on today, and on what date did NV Energy receive the original application?
2. Is this an expansion or a replacement in NV Energy's terms, and which will the application say?
3. If it is an expansion, what does my excess energy credit go from and to, in cents per kilowatt hour?
4. How many excess kilowatt hours did I export in the last twelve months, so we can multiply?
5. What happens to the years left on my 20, confirmed by NV Energy in writing, before I sign anything?

We are a licensed Nevada electrical contractor. Ask us those five and you get the answers in writing, with the handbook open and your own bills on the table. If adding panels costs you more than it returns, that is the answer you will get.

We recheck this page quarterly. Last checked 2026-09-28. If a number here has moved, tell us and we will fix it the same week.