NEM 3.0 Explained: How California's Net Billing Tariff Affects Your Solar Savings
California's NEM 3.0 (Net Billing Tariff) drastically changed solar export rates. Learn what NEM 3.0 means for your solar ROI, true-up bill, battery storage strategy, and how to maximize savings under the new rules.
What Is Net Energy Metering?
Net energy metering, commonly called NEM, is the billing arrangement that determines how much credit you receive when your solar panels send excess electricity back to the grid. For over two decades, NEM was the foundation of residential solar economics in California. The concept is straightforward: when your panels produce more electricity than your home needs, that surplus flows to the grid, and your utility credits you for it.
The value of those credits is what makes or breaks your solar return on investment. Under the original NEM framework, credits were generous enough to make solar an obvious financial win for most California homeowners. But the rules have changed significantly, and understanding the current system is essential before you invest in a solar energy system.
NEM 1.0 and NEM 2.0: The Golden Era of Solar Credits
To understand where we are today, it helps to know where we came from.
NEM 1.0
California's original net energy metering program launched in the mid-1990s and offered the simplest possible arrangement. Every kilowatt-hour you exported to the grid earned a credit equal to the full retail rate of electricity, typically between $0.25 and $0.40 per kWh depending on your utility and rate tier. There were no time-of-use requirements, no non-bypassable charges, and no complexity. NEM 1.0 customers were grandfathered in for 20 years from their interconnection date.
NEM 2.0
NEM 2.0 took effect in 2017 and maintained the core benefit of 1:1 retail rate credits but introduced time-of-use (TOU) rate schedules. This meant the value of your exported electricity varied depending on when you sent it to the grid. Solar exports during peak afternoon hours earned higher credits, while exports during off-peak times earned less.
NEM 2.0 also added small non-bypassable charges of approximately $0.02 to $0.03 per kWh on all grid-consumed electricity. Despite these changes, NEM 2.0 remained highly favorable for solar owners. A typical homeowner with a well-sized system could achieve 80 to 100 percent solar offset on their electricity costs, meaning solar could effectively eliminate their electric bill aside from the minimum monthly connection charge.
What Is NEM 3.0? The Net Billing Tariff
On April 15, 2023, California's NEM 3.0 took effect. Officially called the Net Billing Tariff (NBT), this new framework fundamentally changed the economics of residential solar in the state. The California Public Utilities Commission (CPUC) approved the decision in December 2022 after years of contentious debate between solar advocates, utilities, and consumer groups.
The single biggest change under CA NEM 3.0 is how exported solar energy is valued. Instead of receiving retail rate credits (around $0.30 or more per kWh), solar exports are now compensated at the avoided cost rate, which reflects the wholesale value of electricity to the grid at the time of export.
How Export Rates Work Under NEM 3.0
Under the Net Billing Tariff, export compensation is based on the Avoided Cost Calculator (ACC), a formula that estimates the value your exported electricity provides to the grid. This value considers factors like wholesale energy prices, grid capacity needs, and environmental benefits.
In practice, NEM 3.0 export rates typically fall between $0.05 and $0.08 per kWh during midday hours when solar production peaks. During evening peak demand hours (roughly 4 PM to 9 PM), export values can climb to $0.10 to $0.15 per kWh, but your panels are producing little or no electricity during those hours.
Compare this to the retail rate you pay when consuming grid electricity, which ranges from $0.30 to $0.55 per kWh under current PG&E, SCE, and SDG&E rate schedules. The gap between what you pay for grid electricity and what you receive for exports has widened dramatically.
The Math: NEM 2.0 vs. NEM 3.0
Consider a homeowner who exports 500 kWh per month to the grid:
That is a reduction of approximately 75 to 80 percent in the value of exported electricity. This single change extended the typical solar payback period in California from 5 to 7 years under NEM 2.0 to 9 to 12 years under NEM 3.0 for systems without battery storage.
Understanding Your True-Up Bill
Whether you are on NEM 2.0 or NEM 3.0, your utility uses a true-up billing cycle that every solar homeowner needs to understand. So what is a true-up bill, and what does the true-up bill meaning actually entail for your finances?
What Is a Solar True-Up Bill?
A solar true-up is an annual reconciliation of all the credits and charges that accumulated on your account over the previous 12 months. Rather than settling your balance each month, your utility tracks your net consumption and generation over an entire year and presents a final bill at the end of your annual billing cycle.
During sunny months, your solar panels likely produce more electricity than you use, building up credits. During winter months or periods of heavy air conditioning use, you may consume more than you generate, drawing down those credits. The true-up bill is where everything nets out.
How the True-Up Bill Works
Each month, your utility issues a statement showing your charges and credits, but you only pay the minimum monthly connection fee (around $10 to $15). At the end of the 12-month cycle, your true-up bill calculates:
If your credits exceed your charges, your true-up bill may be zero or close to it. Under NEM 2.0, many homeowners achieved a zero or near-zero true-up bill. Under NEM 3.0, a solar true-up bill of several hundred dollars is more common for systems without batteries, because the export credit values are so much lower.
Strategies to Reduce Your True-Up Bill
Why Batteries Are Now Essential Under NEM 3.0
Before NEM 3.0, batteries were a nice-to-have for backup power but rarely made financial sense because exporting to the grid at retail rates was just as valuable as storing energy. NEM 3.0 completely flipped this calculus.
The Battery Value Proposition
Under the Net Billing Tariff, every kilowatt-hour you store in a battery instead of exporting is worth the difference between the retail rate you would have paid and the export rate you would have received. With retail rates around $0.35/kWh and export rates around $0.06/kWh, each stored kilowatt-hour saves you roughly $0.29.
A typical home battery system (10 to 15 kWh capacity) cycling daily can save $80 to $130 per month in avoided grid purchases. Over a 15-year battery lifespan, this adds up to $14,000 to $23,000 in savings, which more than justifies the $8,000 to $15,000 cost of a battery system after the 30 percent federal tax credit.
Best Battery Options for NEM 3.0
The most popular battery systems for California NEM 3.0 installations include:
Solar-Plus-Storage Payback Under NEM 3.0
When you add a battery to a solar system under NEM 3.0, the combined payback period often drops to 7 to 9 years, which is actually comparable to or better than solar-only payback. The battery earns its keep by allowing you to maximize self-consumption and minimize grid purchases during expensive peak hours.
Strategies to Maximize Your Solar Savings Under NEM 3.0
Even with reduced export rates, solar remains a strong investment in California. The key is adapting your approach to the new rules.
1. Maximize Self-Consumption
The most valuable kilowatt-hour under NEM 3.0 is one you produce and consume yourself, because it offsets electricity you would have purchased at $0.30 to $0.55 per kWh. Achieving a high solar offset percentage through self-consumption is now the primary strategy.
2. Optimize Around Time-of-Use Rates
NEM 3.0 customers are placed on electrification TOU rate schedules where peak rates apply from 4 PM to 9 PM. Since this is after peak solar production, your strategy should focus on:
3. Right-Size Your System
Under NEM 2.0, oversizing your solar system was not a concern because excess production earned full retail credits. Under NEM 3.0, oversizing means exporting more at low rates. Work with your installer to design a system that matches your consumption profile, factoring in planned additions like EV charging or home electrification.
4. Add Battery Storage
As discussed above, batteries transform the NEM 3.0 math. A solar-plus-storage system is now the standard recommendation for California installations. The federal solar tax credit at 30 percent applies to battery systems installed with solar, significantly reducing the upfront cost.
5. Electrify Strategically
If you are planning to add an EV, heat pump HVAC, or heat pump water heater, coordinate these additions with your solar and battery installation. Increasing your daytime electricity consumption through electrification improves self-consumption and reduces low-value exports.
What About NEM 4.0 in California?
The solar industry and consumer advocates are already watching for potential NEM 4.0 changes in California. While no formal proceeding has been opened, several factors suggest further policy evolution:
Potential NEM 4.0 Directions
Protecting Your Investment
Regardless of future NEM 4.0 changes, current NEM 3.0 customers receive a nine-year lock-in period for their export compensation rates. This means the rates you receive when you interconnect are guaranteed for nine years, providing stability for your investment decision.
The best protection against future policy changes is maximizing self-consumption through battery storage and load management. The less dependent your savings are on export credits, the less vulnerable you are to future tariff changes.
Is Solar Still Worth It in California Under NEM 3.0?
Despite the less favorable export rates, the answer is definitively yes, especially when you consider:
The economics have shifted from "solar pays for itself through export credits" to "solar pays for itself by reducing grid purchases." The destination is the same; the route has changed.
The Bottom Line
California's transition from NEM 2.0 to NEM 3.0 represents the most significant policy shift in residential solar economics since net metering began. Export rates dropped from retail value ($0.30+/kWh) to avoided cost ($0.05 to $0.08/kWh), making battery storage essential rather than optional. Your solar true-up bill will reflect these changes, and understanding how the annual reconciliation works empowers you to optimize your system and consumption patterns.
The homeowners seeing the best results under NEM 3.0 are those who pair solar with battery storage, maximize self-consumption, and optimize around TOU rate schedules. With this approach, solar in California remains one of the best investments a homeowner can make.
SmartEnergyUSA connects you with vetted California solar installers who specialize in NEM 3.0-optimized solar-plus-storage systems. Compare free quotes from top-rated local companies and find the system design that maximizes your savings under today's rules. [Get your free solar quote today](/solar-companies/california/).
