By Claire WhitakerUpdated November 2026
Net energy metering in California, often shortened to NEM, was the state’s long-running system for crediting homeowners who send solar power back to the grid. Since April 2023, most new residential solar customers of the big investor-owned utilities are on the successor program, net billing, which pays a lower export rate. For homeowners already enrolled under the legacy NEM rules, staying put usually wins. For anyone interconnecting now, the comparison comes down to how much you use during the day, whether you plan to add a battery, and how much you can offset with exports.
This article compares the two options as they apply to California homeowners. Where a detail depends on your utility or rate plan, we point out what to check on your own bill rather than guess. Tariff rules change, so confirm current terms with your utility before you sign a contract.
Quick Comparison Table
| Criterion | Net Energy Metering (NEM 2.0 / legacy) | Net Billing Tariff (NEM 3.0) |
|---|---|---|
| Who it applies to | Customers interconnected before April 15, 2023 | Most new interconnections from April 15, 2023 onward |
| How exports are valued | Exported kWh are credited one-for-one against imported kWh (retail-rate netting) | Exports are paid at a time-varying avoided-cost rate that is usually much lower than retail |
| Time-of-use sensitivity | Low: a kWh exported at 5 p.m. offsets a kWh used at 2 a.m. | High: the value of exports depends on the hour they are sent |
| Battery economics | Batteries add value mainly through backup and time-shifting; less pressure to store | Batteries are often central to making the system pay off |
| Monthly billing | Credits roll over monthly; annual true-up applies | Net exports are tracked through the billing cycle with the same annual true-up framework |
| Sizing strategy | Systems are often sized to match or exceed annual usage | Systems are typically sized to cover self-consumption, with exports secondary |
| Best fit | Existing legacy customers and high-export homes | New customers with high daytime use or battery plans |
Compensation Rates: Which Pays More for Exports?
Winner: legacy net energy metering in California, by a wide margin for exported power.
Under NEM 2.0 and the older NEM 1.0 terms, a kilowatt-hour sent to the grid is credited against a kilowatt-hour you draw later at the same retail rate. The effect is that your home acts like a bank: you deposit kWh at noon and withdraw them at 8 p.m. Under net billing, the credit for exports is set by the utility’s avoided-cost calculator, which pays considerably less than the retail rate, especially in the middle of the day when solar output is highest and wholesale prices are lowest. Your imports in the evening are still billed at retail, so the gap between what you sell and what you buy widens.
A practical check: look at your current bill and find the line items for export credits and retail energy charges. If you are on legacy NEM, the export credit should track your retail energy rate closely. If you are on net billing, expect the export rate to be a fraction of your retail rate for most daylight hours.
Time-of-Use Matching: Which Works Better With Your Daily Schedule?
Winner: legacy NEM, for households whose usage and solar production do not line up.
Consider a home that runs its air conditioning in the late afternoon and evening but has a solar array that peaks around noon. Under legacy NEM, the midday surplus banks at full value and offsets the evening load. Under net billing, that same midday surplus earns the lower export rate, and the evening load is bought at the higher retail price. The result is that a homeowner’s bill can rise even when the system produces a large annual total.
Net billing rewards households that consume most of their solar output on-site during daylight hours. If you work from home, run dishwashers, pool pumps, or EV chargers while the sun is out, the gap narrows. A useful exercise is to pull 12 months of interval usage from your utility’s portal and compare it against a typical solar production curve for your ZIP code. The overlap tells you how much of your generation you will consume directly, which is the number that matters most under net billing.
Battery Storage: Which Option Makes Storage Pay Off?
Winner: net billing, because a battery is close to required for strong economics.
Under legacy NEM, a battery mostly provides backup power during outages and perhaps modest time-shifting value. Since exports already earn near-retail credit, there is less pressure to store energy. Under net billing, a battery can capture midday solar that would otherwise be exported cheaply and discharge it during the early evening peak, when retail rates are highest. Many installers pair net billing systems with batteries for this reason, and California’s self-generation incentive and utility programs have historically been structured to encourage storage alongside new solar.
If you are weighing a battery, look at the utility’s time-of-use schedule. The spread between peak and off-peak prices determines how much a battery can earn by shifting energy. A wide spread favors storage; a narrow one makes the battery a backup-only investment.
Sizing and Design: Which Approach Makes More Sense?
Winner: legacy NEM for oversized systems; net billing for right-sized, self-consumption systems.
Under legacy NEM, many homeowners sized arrays to produce roughly 100 percent of their annual consumption, sometimes more, because every surplus kWh was valuable. Under net billing, oversizing mostly sends power to the grid at low rates, so the optimal design shifts toward covering daytime loads and leaving the remainder as a modest export. Tilt, orientation, and shading still matter. A south-facing roof with unshaded hours from 10 a.m. to 2 p.m. will outperform a west-facing array with afternoon shade regardless of which program you use.
Installers should provide a production estimate and an hourly export forecast under net billing. Ask for both, and compare them against your usage data before accepting a design.
Billing Mechanics and True-Ups
Winner: a tie, since both systems use monthly billing and an annual reconciliation.
Both programs track net usage on your monthly bill. Legacy NEM customers accumulate kWh credits that can carry forward within the year, and any balance is trued up annually, often with a payment or credit depending on the utility’s rules. Net billing customers see a similar cycle, but with dollar-denominated export credits. Read your bill carefully during the first 12 months. Confirm the billing cycle, the true-up date, and whether unused credits expire, because these details vary by utility and tariff.
Eligibility and Enrollment
Winner: legacy NEM, if you already qualify; otherwise net billing is the default path for new systems.
Your interconnection date determines which tariff applies. Systems approved before April 15, 2023 generally remain on legacy NEM for the life of the contract, even if you sell the home, subject to the terms of your agreement. New systems are placed on net billing. Some utilities and municipal providers operate under different rules, and some customers may have grandfathered arrangements. The interconnection agreement is the document to check.
If you are unsure which tariff you are on, call your utility’s solar or customer generation department, or check the rate schedule shown on your bill.
Which Should You Choose?
- Choose legacy NEM if you are already interconnected under the older rules and your system exports a meaningful share of its output.
- Choose net billing if you are a new customer whose household uses most of its solar power during the day.
- Choose a battery-paired net billing system if your utility has a wide time-of-use price spread and you want to shift midday solar to the evening.
- Choose a smaller, self-consumption-focused array if you want to avoid depending on export credits.
- Choose to stay on legacy NEM and not upgrade if your system is working well and any change would reset your tariff status.
- Get a professional review if your household has an unusual usage pattern, an EV, or a complex rate plan, since a licensed solar designer or energy consultant can model your bill under both tariffs.
Hardware that supports either approach includes monitoring equipment and battery systems. Consider a monitoring device so you can track imports, exports, and self-consumption in real time. Examples include the Emporia Vue 3, a whole-home energy monitor with circuit-level tracking, and the Enphase Encharge 10 battery, a modular storage system that pairs with Enphase microinverters. View on Amazon View on Amazon
For a broader look at how tariffs work, see Net Metering in California: How It Works and What Homeowners Need to Know. If you are preparing paperwork for interconnection, Net Energy Metering Application: A Step-by-Step Guide for Homeowners walks through the process. Homeowners who want to understand what happens at the end of the year may find Net Energy Metering True-up: How It Works and What Homeowners Should Check useful. Utility-specific details are covered in SCE Net Energy Metering Program: How It Works and Who Qualifies and Southern California Edison Net Metering (2026): Which Is Better for Homeowners?. For a comparison of physical and virtual arrangements, see Virtual Net Energy Metering vs Physical Net Metering: Which Is Better?.
FAQ
Is net energy metering in California still available for new customers?
For most residential customers of the large investor-owned utilities, new interconnections since April 15, 2023 are placed on net billing rather than legacy NEM. Check with your utility, since municipal providers and specific programs can differ.
Does California net energy metering pay cash for excess solar?
Legacy NEM generally credits exports against future usage at retail value rather than paying cash each month. Excess credits are settled at the annual true-up, and the mechanics depend on your utility’s tariff.
Will my bill go up if I switch from legacy NEM to net billing?
Switching is not typically optional for existing customers, but if you add capacity or make certain changes, your system may be reviewed under current rules. Under net billing, a home with heavy evening usage may see higher bills than under legacy NEM, so modeling both scenarios before any change is wise.
Do I need a battery to make net billing worthwhile?
Not always. Households with high daytime self-consumption can do well without storage. However, many homeowners find a battery helps capture midday production and use it during expensive evening hours, especially when the utility’s peak-to-off-peak spread is wide.
Who can help me compare the two tariffs for my home?
A licensed solar installer, an independent energy consultant, or your utility’s customer generation team can model your usage against both tariffs. Because tariff rules and rates change, ask for a written analysis based on your last 12 months of interval data.
Conclusion
Net energy metering in California favored homeowners who could bank midday solar at retail value, and that remains the best deal for legacy customers. For new systems, net billing shifts the math toward self-consumption, time-of-use awareness, and often battery storage. The right answer depends on your interconnection date, your daily usage pattern, and your utility’s rate design. Pull your bills, check your interconnection agreement, and model both tariffs before you commit. Because these rules and rates change, verify current terms with your utility or a qualified solar professional before making any decision.
About Claire Whitaker
Claire Whitaker is part of our editorial team and reviews and edits our home solar guides, checking product details against manufacturer specifications and owner feedback.
