A lot of Bay Area homeowners made the same calculation: buy an EV, pair it with rooftop solar, and watch the fuel costs disappear. Neighbors with systems installed before 2023 made it look effortless. What those neighbors don’t always mention is that the rules changed. Since April 2023, every new solar installation in PG&E territory operates under NEM 3.0, the Net Billing Tariff, which cut export credits by roughly 75 percent. Sending excess solar to the grid and buying it back later no longer makes financial sense. Self-consumption does.
At Cobalt Power Systems Inc, we’ve been designing solar systems across the Bay Area since 2003 and have installed more than 3,500 photovoltaic systems for homeowners and businesses throughout the region. The questions we hear most often now come from EV owners who want to understand how to capture real value from a solar-plus-charging setup under today’s rules. Not the rules their neighbor used five years ago.
How Solar & EV Charging Work Together at Home
Solar panels generate direct current (DC) electricity; an inverter converts it to the alternating current (AC) that powers your home. Your EV charger draws from whatever source is powering the house at that moment, which means when the sun is producing, the charger draws from solar. When it isn’t, it draws from the grid. There’s no dedicated solar-to-car pathway. It’s all one home circuit.
Three charging scenarios play out in a solar home. Direct daytime charging uses solar output in real time. Grid-assisted charging fills the gap when solar production falls short of demand. Battery-backed charging handles nighttime or overcast days by discharging stored solar rather than pulling from the grid. Which path dominates depends on how your system is sized and when you charge.
For solar EV charging to be practical, a Level 2 charger (technically called an EVSE, or Electric Vehicle Supply Equipment) running on a dedicated 240V circuit is the standard. A Level 2 unit delivers 20 to 30 miles of range per hour; a standard 120V outlet delivers 3 to 5. Most Bay Area drivers charging overnight don’t notice the difference on full-charge mornings, but the gap becomes real when you’re trying to align charging with your solar production window.
Why NEM 3.0 Changes the Math for Bay Area Homeowners
NEM 3.0 went into effect April 15, 2023 and applies to every new solar system interconnected in PG&E territory. Under the old NEM 2.0 structure, export credits were priced close to retail rates, making it reasonable to export excess solar and buy it back later. Under NEM 3.0, export credits are based on avoided cost, typically $0.05 to $0.08 per kWh, while retail rates in PG&E territory often run four to five times that. Exporting solar and buying it back is now a losing trade.
PG&E’s EV2-A rate plan makes the timing math concrete. Off-peak hours run from midnight to 3:00pm every day. Peak hours run from 4:00pm to 9:00pm, with a partial-peak window covering 3:00pm to 4:00pm and 9:00pm to midnight. Bay Area solar panels typically produce their strongest output between 10:00am and 2:00pm, squarely inside the off-peak window. That makes midday the ideal time to charge an EV directly from solar and to fill a battery for discharge during the evening peak. A smart EV charger that can be scheduled or respond to solar output and rate signals handles that alignment automatically, without manual management each day.
Contact Cobalt Power Systems Inc at (650) 817-7791 to schedule a free consultation or to learn more about Solar-Powered EV Charging for Bay Area Homes.
Why Battery Storage Changes the Economics under NEM 3.0
Battery storage isn’t required for solar EV charging to work, but under NEM 3.0 it fundamentally changes the numbers. Without storage, excess midday solar that can’t be used in the moment gets exported at $0.05 to $0.08 per kWh. With storage, that same surplus gets saved and discharged during PG&E’s peak window, offsetting electricity that would otherwise cost four to five times the export credit. That gap is why battery attachment rates on new California solar installations have climbed sharply since NEM 3.0 took effect.
For an EV owner, the picture is even more compelling. An average EV in Bay Area driving conditions consumes roughly 10 to 15 kWh per day. A home battery system sized to cover evening household loads, EV charging, and morning draw before the next solar cycle shifts nearly all grid exposure to the lowest-rate overnight window and keeps the household insulated from the evening peak entirely.
We work with Tesla Powerwall and Enphase IQ Battery products, both of which integrate with their respective monitoring ecosystems. Battery selection depends on your home’s load profile, your EV’s daily demand, and how the system is configured for backup versus rate optimization. We treat the battery and the EV charger as components of one energy plan rather than separate add-ons, because sizing them independently tends to produce undersized storage or an oversized panel array.
Sizing a System That Handles Both Your Home & Your EV
Adding an EV to a home’s energy demand isn’t trivial. At 10 to 15 kWh per day, a single EV can increase a household’s electricity consumption by 30 to 50 percent. A system designed without accounting for that load from the start will self-consume less and require additional panels later, at a higher cost per watt than getting the sizing right initially.
The physical factors that shape system design include more than electricity demand:
- Roof orientation and available area determine how many panels can be placed at optimal angles for Bay Area sun exposure.
- Shading from trees, neighboring structures, or roof features can significantly reduce effective output if not mapped at the design stage.
- Electrical panel capacity sets a hard limit; a home with an older 100-amp panel may need a service upgrade before a Level 2 charger circuit can be added safely.
- Driving patterns and charge frequency affect how much storage the system needs versus how much it can rely on daytime direct charging.
Our in-house CAD team designs each system around the specific property, vehicle, and household usage rather than applying a generic formula. Every project includes permitting and utility interconnection through PG&E, which we manage as part of the installation process. Homeowners don’t coordinate separately with the utility.
What Incentives Still Apply in 2026
The incentive landscape shifted significantly at the end of 2025. Bay Area homeowners planning a solar EV charging system should know what’s current before building rebates into their project budget.
Federal 30% Residential Clean Energy Credit
The federal Investment Tax Credit, which covered 30% of installed system costs, expired December 31, 2025 for systems purchased with cash or a conventional loan. If you’re exploring a solar lease or power purchase agreement, ask specifically about third-party-owned system eligibility, which may carry different federal treatment through 2027. Don’t assume the credit applies to your situation without confirming your financing structure.
California SGIP Battery Rebate
California’s Self-Generation Incentive Program (SGIP), which provided rebates for home battery storage, closed its general market ratepayer budgets December 31, 2025. As of mid-2026, the RSSE budget for income-qualifying households is accepting waitlist applications only. Homeowners who were planning to factor SGIP into their battery economics should verify current program status directly before making any project decisions.
Local & Utility Programs
PG&E and municipal utilities periodically offer additional programs for EV charging equipment and demand response participation. Availability and funding levels change frequently, which is why we include a current incentive review as part of every consultation rather than publishing a static list that ages out quickly.
Designing for How Bay Area Solar Actually Works Today
Solar-powered EV charging works well when the system is designed around self-consumption, smart timing, and storage. It works poorly when it’s designed around export assumptions that no longer apply under NEM 3.0. The difference between those two outcomes is almost entirely in how the system is planned before a single panel goes on the roof.
If you’re considering combining solar with an EV charger, or expanding an existing system to cover a new vehicle, we can walk through the specifics of your home, your commute, and your current rate plan to show you what a well-designed system looks like. We’ve been doing this work across the Bay Area since 2003. Reach us at (650) 817-7791 to get started.