PWP interconnection, EV charging, and battery planning in Pasadena 91107

PWP initial review should precede reliance on the final sales model

PWP's published process begins with a PowerClerk application and utility review before the project moves into the City permit and construction phase.

Ask the installer what system size, storage configuration and load history are being submitted to PWP and whether those details match the signed proposal.

If PWP requests corrections, update the production and financial model before installation rather than assuming the original sales estimate still applies.

EV charging should be part of the PWP load forecast

Estimate annual miles and home-charging share before finalizing system size. Future EV demand should be visible in the utility application and financial model.

If multiple EVs are expected, managed charging may reduce simultaneous service demand even though annual energy use remains similar.

Keep the charging assumption consistent across service capacity, solar sizing and battery planning.

Battery storage should be evaluated under Pasadena's municipal rules

Ask the installer how storage affects the PWP application and which interconnection agreement applies to the combined inverter capacity.

For backup, identify critical circuits and desired runtime. For normal operation, ask how the battery is expected to interact with PWP's rate and compensation structure.

Do not accept an SCE-specific battery savings model for a PWP account.

Permit, inspection, meter work, and PTO are separate milestones

PWP's process distinguishes initial utility review, City permits and construction, inspection signoffs, PWP inspection, meter installation and permission to operate.

Ask for a milestone schedule that identifies who controls each step and what documentation is required before the next one can begin.

A completed physical installation does not mean the system should be energized before PWP permission to operate is issued.

Service capacity should include future electrification

EV chargers, batteries, heat pumps and solar interconnection can all affect the main service. Ask whether the existing equipment supports the complete plan.

If an upgrade is recommended, request the electrical reason and ask whether load management can reduce the scope.

Any PWP service work should be included in the project timeline.

Pasadena 91107 homeowner checklist

Gather PWP bills, EV plans, roof information, panel photos and battery goals.

Confirm PowerClerk application assumptions, City permit responsibility and interconnection agreement before financing.

Compare total cash price, financed price, service upgrades and long-term support.

How Home Solar Simplified reviews a solar proposal

Every local guide uses the same homeowner-first review standard so a proposal can be evaluated without relying on a sales presentation. Start with the home's actual electric bills and identify which future loads are genuinely likely: electric vehicles, heat pumps, electric water heating, pool equipment, an accessory dwelling unit, or battery storage. Ask the installer to separate today's usage from future assumptions instead of blending them into one unexplained annual number.

Next, compare the physical system. Write down the proposed DC system size, first-year production estimate, degradation assumption, module and inverter models, battery usable capacity and power rating if storage is included, roof planes used, shade assumptions, attachment method, equipment locations, and any service-panel or roofing work. The production model should match the final permitted layout. If panels move during engineering, HOA review, planning review, or permit corrections, request an updated production estimate before installation.

Then compare money on a cash-price basis before looking at monthly payments. Ask for the cash price of the solar array, battery, roof work, service upgrade, EV charger, trenching, permits, and other add-ons as separate line items. If financing is used, compare the financed amount, interest rate, term, dealer fees or prepaid finance charges, total scheduled payments, and prepayment rules. Tax-credit assumptions should be treated as estimates for discussion with a qualified tax professional, not as guaranteed discounts from the contractor.

Review the utility assumptions separately. The proposal should identify the actual electric utility, current rate structure, estimated self-consumption, exports, remaining grid purchases, and any battery dispatch strategy. A city, ZIP code, or neighboring home does not prove the exact service arrangement at a property. Utility rules, rates, interconnection requirements, and equipment eligibility can change, so the installer should confirm the current rules for the specific account before the homeowner relies on projected savings.

Finally, review responsibility after the sale. Ask who handles permit corrections, utility interconnection, inspection failures, monitoring problems, inverter or battery warranty claims, roof leaks near attachments, and future array removal for roof work. Keep the signed contract, approved plans, equipment cut sheets, inspection record, permission-to-operate documentation, warranties, and final one-line electrical diagram together. A solar project should remain understandable years after the original salesperson is gone.

When comparing two or three proposals, normalize them before deciding. Put the same fields into one worksheet: cash price, financed price, system size, first-year production, estimated annual consumption, future-load assumptions, battery capacity and power, roof work, service upgrades, permit responsibility, workmanship warranty, equipment warranties, monitoring support, and the estimated utility bill that remains. If one proposal uses a different roof layout, rate assumption, financing term, utility escalation rate, or battery operating strategy, mark that difference instead of treating the monthly payments as directly comparable. Ask each contractor to correct obvious assumption mismatches so the homeowner is comparing systems on equal footing. The lowest payment is not necessarily the lowest project cost, the largest array is not necessarily the best value, and the highest production estimate is not necessarily the most credible. A useful comparison makes the assumptions visible enough that a homeowner can explain why one proposal is stronger without repeating a salesperson's slogan.

Related homeowner research

Adjacency QA: ZIP links are topical and geographic-navigation links, not claims of municipal physical adjacency.

Frequently asked questions