A solar-plus-battery PPA can give an eligible SDG&E homeowner access to solar generation and designed backup coverage without an upfront equipment purchase where the offer provides it. To compare proposals fairly, look at the full provider payment—not just the advertised cents per solar kilowatt-hour.
If one proposal lists a separate monthly battery fee and another includes storage in its energy price, neither format alone tells you which is the better fit. Ask each provider to show the complete payment schedule and the equipment and service included.
Identify what each charge buys
The CPUC solar guide explains that the provider owns the solar system under a PPA and sells its generated electricity. It also points homeowners toward disclosures covering solar and battery costs, ongoing payments and escalation.
For each written proposal, identify the solar energy rate, production used for billing, any separate battery payment and all upfront charges. Confirm whether storage appears in the same agreement or a separate document. A zero-upfront offer can still have substantial ongoing payments; it does not mean free electricity.
If the battery payment is fixed, ask whether it increases later, when it starts and ends, and what happens during a covered service interruption. These are questions for the actual contract, not assumptions about every PPA.
Compare one year using the same assumptions
Consider two entirely hypothetical proposals with identical equipment, backup coverage, service terms and 10,000 kWh of billable solar production in year one. Assume no upfront charges or other provider fees:
- Proposal A charges an invented $0.20 per solar kWh plus $30 monthly for the battery: 10,000 × $0.20 + 12 × $30 = $2,360.
- Proposal B charges an invented $0.23 per solar kWh with the battery included and no separate storage fee: 10,000 × $0.23 = $2,300.
Under those assumptions, B’s provider charges are $60 lower for that year despite its higher energy rate. These figures are arithmetic examples, not available offers, market prices or savings predictions. Neither total includes the remaining utility bill.
Repeat the comparison with each proposal’s actual production estimate and later-year payment schedules. Do not silently hold a battery fee constant if its contract includes an increase, or assume two agreements end together.
Add the SDG&E bill separately
For a home on SDG&E’s Solar Billing Plan, import prices and export credits depend on timing. Batteries can shift solar energy toward later household use, but a PPA rate is not an export-credit rate.
SDG&E also explains that Community Power or Clean Energy Alliance sets generation import charges and generation export credits for its respective customers. Confirm your generation provider and applicable plan before accepting the remaining-bill estimate.
Ask both proposals to use the same household usage, tariff assumptions and backup reserve for comparison. Include grid purchases, applicable fixed charges, battery losses and export credits. Our solar production and exports guide explains the underlying distinction between generated energy and energy sent to the grid.
Match the backup and service you receive
Price comparisons become less useful when one proposal backs up fewer circuits or includes different service coverage. Compare usable storage, output limits, supported loads, installation work, battery ownership, maintenance, replacement and home-sale transfer terms.
PG&E’s general battery guidance explains why charge, household demand and supported circuits affect backup. Those equipment principles also matter when reviewing an SDG&E-area proposal: a monthly payment does not promise unlimited runtime, and solar recharge needs suitable sunlight and compatible equipment.
Bring both itemized proposals to the West Coast Alternatives homeowner journey. Clear annual costs and matched backup expectations make it easier to evaluate a qualifying no-upfront PPA, including its term, escalator and long-term responsibilities, without assuming guaranteed savings.