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California Solar Guide · 2026

The Complete Guide to NEM Solar Expansion in California (2026)

You have a grandfathered NEM rate. Now you can legally add 1 kW of solar to your system — permit-free, in under an hour — and lock in bigger savings before it's too late.

~$500
Avg. annual savings (PG&E)
~4 yrs
Typical payback period
45 min
Average setup time
25+ yrs
Panel performance warranty
The Opportunity

What Is NEM Solar Expansion?

NEM Solar Expansion is the process of adding new solar panels to an existing, grandfathered Net Energy Metering system. The goal is to increase your home's solar energy production to offset a larger portion of your electricity bill — especially if your energy usage has grown since your original installation.

For years, the main obstacle to expansion was regulatory. Adding significant capacity to an existing system typically triggered a new interconnection agreement, forcing homeowners off highly favorable NEM 1.0 or NEM 2.0 rates and onto the much less advantageous NEM 3.0 (the Net Billing Tariff).

The key exception: A California Public Utilities Commission decision allows homeowners to add up to 1 kilowatt (kW) of solar capacity to their existing systems without losing their grandfathered NEM status. This is a permit-free "top-up" that can add hundreds of dollars in savings each year.

It's the smartest, most cost-effective way for California's NEM 2.0 customers to fight back against rising electricity costs. New plug-in solar technology — already deployed by 4 million Germans — has arrived in the US market with California Energy Commission certification, making it simpler than ever.

Why 2026 Is Critical

Why Expand Your Solar System Now?

For homeowners with NEM 1.0 or 2.0 systems, a combination of expiring tariffs and relentless rate hikes from California's major utilities creates a powerful incentive to act quickly.

The NEM 3.0 Transition Lock-In

The transition to NEM 3.0 in 2023 fundamentally changed the economics of solar in California. Under NEM 3.0, the value of exported solar energy was cut by approximately 75% compared to the retail rates offered under NEM 2.0.

By expanding your system under your existing NEM 2.0 agreement, you get to apply those favorable, high-value export rates to the energy produced by your new panels. Once your NEM 2.0 agreement expires, this opportunity is gone forever.

Unprecedented Utility Rate Increases

Every kilowatt-hour you generate and use at home is more valuable than ever. Expanding your system directly counters these price hikes and gives you more control over your energy future.

Know Your Rate

NEM 1.0 vs 2.0 vs 3.0 — What You Need to Know

The table below shows why grandfathered NEM 2.0 customers are in such a valuable position — and why acting before your term expires matters.

Feature NEM 1.0 NEM 2.0 ★ NEM 3.0 (Net Billing)
Export Credit Rate Full Retail Rate Full Retail Rate (minus small fees) Avoided Cost Rate (~75% less)
Contract Term 20 Years 20 Years 9 Years
Rate Structure Flat Rates Time-of-Use (TOU) TOU + Monthly Fixed Charges
Typical Payback 4–6 Years 5–7 Years 9–12+ Years
Status Program Closed Closed Program Closed Closed Current for new solar Active

★ If you have a NEM 2.0 system, you should act now. Expanding by 1 kW allows you to maximize your production under excellent rates before your 20-year term expires.

Simple Setup

How Plug-In Solar Expansion Works

Forget what you know about traditional solar installations that take days or weeks. A modern solar expansion kit is designed for simplicity and speed. Bright Saver has engineered systems specifically for this purpose as a 501(c)(3) nonprofit dedicated to making solar accessible.

The process is as simple as setting up a new appliance:

1

Unbox the Kit

Your kit arrives with everything you need: four solar panels, a microinverter, mounting racks, and a single cable.

2

Position the Mounts

The ground-mounted racks can be placed in a sunny spot in your yard, on a patio, or any flat, unobstructed surface.

3

Attach the Panels

The panels are designed to be manageable, weighing only 26 lbs each. They easily attach to the mounts — no heavy lifting required.

4

Connect the Cable

The panels connect to a central microinverter, which consolidates the power into a single, standard AC plug.

5

Plug In

Simply plug the system into a dedicated outdoor NEMA 5-15 or 5-20 outlet. Done. The entire setup takes about 45 minutes.

The system is UL-certified and self-contained. It requires no changes to your main electrical panel or existing solar system wiring, which is why it falls outside the scope of most permitting requirements.

Your Return

Savings Calculator: What You'll Actually Save

A 1 kW expansion typically generates between 1,500 and 1,600 kWh of clean energy per year, depending on your location and sun exposure. Here's what that means for your utility bill:

PG&E
$540
per year
~3.7 yr payback on NEM GO
SCE
$480
per year
~4.2 yr payback on NEM GO
SDG&E
$450
per year
~4.4 yr payback on NEM GO

After payback, the system continues generating free electricity for 25+ years. With a ~4-year payback and a 25+ year lifespan, you'll enjoy 20+ years of free electricity after break-even — thousands of dollars in savings and protection against future rate hikes.

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🌸 Spring Sale · Ends March 31, 2026

Save $200 on Any Bright Saver Solar Kit

NEM GO at $1,999  ·  NEM Pro 4P at $2,148 (reg. $2,348)

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Our Solar Kits

Product Options for NEM Expansion

Bright Saver offers two plug-in solar kits designed for different needs. Both are permit-free and require no changes to your main electrical panel.

Ships to Your Door

NEM GO

1 kW Plug-In Solar Kit
$1,999
Spring Price
Free shipping in California
Capacity 1,000W (4 × 250W)
Annual Production ~1,500 kWh
Setup Time ~45 minutes
Panel Warranty 25 years
Delivery Ships to your door
Maximum Performance

NEM Pro 4 Glass Panels

1,600W Panels · 1 kW Output
$2,148
$2,348
Spring Sale
Warehouse pickup only — Oakland
Panel Capacity 1,600W panels
Inverter Output Clips to 1 kW
Low-Light Performance Superior (mornings, cloudy)
Panel Warranty 25 years
Availability Oakland warehouse pickup
Setup Guide

Installation & Setup

Installing your Bright Saver solar expansion kit is designed to be a simple DIY project — no electrician required.

The system is self-contained and requires no changes to your main electrical panel or existing solar system wiring.

⚡ Municipal Utility Customers: Check Your Rules

The CPUC rules in this guide apply to California's three main investor-owned utilities: PG&E, SCE, and SDG&E. If your electricity comes from LADWP, SMUD, or City of Palo Alto Utilities, check directly with your utility — municipal utilities have separate solar interconnection regulations.

Common Questions

Frequently Asked Questions

For a system up to 1 kW that plugs into an existing outlet and is not permanently attached to your home, most California cities in IOU territory do not require a permit. It's always good practice to check your local city's building department for any specific local ordinances.

California Civil Code Section 714 severely limits the ability of HOAs to prohibit solar installations. They may have reasonable placement restrictions, but they cannot stop you. Since these kits are ground-mounted, they are often less contentious than rooftop systems.

Panels come with a 25-year performance warranty. The microinverter has a 10-year warranty.

Each panel weighs approximately 26 pounds — manageable for a single person during setup.

The system is weatherproof and handles wind and rain. Production is lower on overcast days and stops at night, as with all solar. The NEM Pro's larger panels are specifically designed for better low-light performance — producing more power on cloudy days and in mornings and afternoons.

With a roughly 4-year payback and a 25+ year lifespan, you'll enjoy 20+ years of free electricity after break-even — thousands of dollars in savings and strong protection against future rate increases.

Systems come with an optional smart plug or monitoring app (depending on the microinverter model) that connects to your home Wi-Fi for real-time tracking of energy production and savings.

Take Action

Your Next Steps

Adding a 1 kW solar expansion kit to your NEM 2.0 system is one of the highest-return home improvements you can make in 2026. As a nonprofit, our mission is to provide clear, honest information to help you make the best energy decisions for your home.

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Questions? Our nonprofit team is ready to help.

408-345-5768