APS vs. SRP Solar Battery Rates in 2026: Which Utility Saves You More?

If you own solar panels and a home battery in Arizona, the utility you happen to be on — APS or SRP — can mean the difference between saving $50 a month and saving $130 a month. Both Arizona Public Service (APS) and Salt River Project (SRP) offer time-of-use rate plans that reward battery owners for shifting energy consumption away from peak hours, but the mechanics are very different. APS relies on steep peak-to-off-peak price spreads. SRP layers demand charges on top of TOU pricing. Understanding how each utility structures its rates is the single most important step you can take before investing in battery storage.

This guide breaks down every major APS and SRP rate plan relevant to solar battery owners in 2026, runs real savings calculations, and tells you which utility actually gives you the better return on your battery investment.

How Solar Batteries Save Money on Arizona Utility Bills

Before diving into plan-by-plan comparisons, it helps to understand the two main ways a home battery saves you money on your electric bill in Arizona.

TOU arbitrage is the first mechanism. Both APS and SRP charge dramatically more for electricity during afternoon and evening peak hours than they do overnight or in the early morning. A battery charged by your solar panels during midday — when your panels produce the most and rates are low — can then discharge during peak hours when rates spike. You avoid buying expensive grid power and instead use stored solar energy. The wider the gap between peak and off-peak rates, the more money you save per kilowatt-hour shifted.

Demand charge reduction is the second mechanism, and it applies primarily to SRP customers. Several SRP rate plans include a demand charge based on your single highest hour (or 30-minute interval) of grid draw during the billing period. A battery can shave that peak draw by kicking in during high-usage moments, reducing your demand charge significantly. APS does not currently apply residential demand charges on most TOU plans, which simplifies the math for APS customers but also limits one avenue of savings.

APS Solar Battery Rate Plans in 2026

APS offers three primary time-of-use rate plans that solar and battery customers gravitate toward. All three share the same basic structure — cheaper power at night, expensive power in the late afternoon and evening — but the size of the peak-to-off-peak spread varies, and that spread is what determines your battery savings.

APS Saver Choice

Saver Choice is the entry-level TOU plan and the default for many APS residential customers. The peak window runs from 4 PM to 7 PM on weekdays during the summer billing season (roughly May through October) and from 5 AM to 9 AM and 5 PM to 9 PM in the winter.

Summer off-peak: approximately $0.07 to $0.08/kWh
Summer on-peak: approximately $0.24 to $0.27/kWh
Winter off-peak: approximately $0.07 to $0.08/kWh
Winter on-peak: approximately $0.14 to $0.16/kWh

The peak-to-off-peak spread on Saver Choice during the summer is roughly $0.17 to $0.19 per kWh. For a battery discharging 10 kWh during the 3-hour peak window each weekday, that works out to about $1.70 to $1.90 in savings per day, or roughly $37 to $42 per month during the summer billing season. Winter savings are lower because the spread narrows.

Saver Choice is a solid plan for battery owners who want moderate savings with relatively low rate risk. The peak window is short and predictable.

APS Saver Choice Plus

Saver Choice Plus is where APS solar battery rates start to get interesting. The plan has a wider peak-to-off-peak differential, which means your battery earns more for every kWh it shifts. Peak hours are the same 4 PM to 7 PM window in summer.

Summer off-peak: approximately $0.06 to $0.07/kWh
Summer on-peak: approximately $0.29 to $0.35/kWh
Winter off-peak: approximately $0.06 to $0.07/kWh
Winter on-peak: approximately $0.15 to $0.18/kWh

The summer spread here is roughly $0.23 to $0.28 per kWh. That same 10 kWh daily battery discharge now saves you $2.30 to $2.80 per day, or roughly $50 to $62 per month in the summer. Over a full year including milder winter months, expect annual savings between $500 and $650 from TOU arbitrage alone on Saver Choice Plus.

This plan is the sweet spot for most APS battery owners. The off-peak rates are among the lowest available from any Arizona utility, which also makes overnight charging of your battery from the grid viable on days when solar production is low (monsoon season, for example).

APS Saver Choice Max

Saver Choice Max pushes the peak-to-off-peak differential to its widest point. This plan is designed for customers who are confident they can stay off the grid during peak hours, making it the most aggressive TOU plan APS offers and the best match for a well-sized battery system.

Summer off-peak: approximately $0.06/kWh
Summer on-peak: approximately $0.40 to $0.47/kWh
Winter off-peak: approximately $0.06/kWh
Winter on-peak: approximately $0.18 to $0.22/kWh

The summer spread can reach $0.34 to $0.41 per kWh. A 10 kWh daily discharge during peak hours saves $3.40 to $4.10 per day, which translates to roughly $75 to $90 per month in the summer. Annualized savings on Saver Choice Max can exceed $750 to $900 per year for a household that consistently avoids peak grid draw.

The catch is risk. If your battery runs out before the peak window ends and you pull from the grid at $0.47/kWh, those costs add up fast. Saver Choice Max is best suited for homes with a well-sized battery (13.5 kWh or larger), moderate peak-hour energy usage, and disciplined energy habits. Many battery owners pair this plan with smart thermostats that pre-cool the house before 4 PM.

APS Net Metering and Export Rates

APS phased out traditional one-to-one net metering for new solar customers several years ago. As of 2026, new APS solar customers receive an export rate of approximately $0.03 to $0.05/kWh for excess solar energy sent back to the grid, depending on the rate plan and time of day. This is a fraction of the retail rate.

This low export rate is actually one of the strongest arguments for pairing solar with a battery on APS. Without a battery, your excess midday solar generation gets exported at 3 to 5 cents per kWh. With a battery, you store that energy and use it during peak hours when it would cost you 25 to 47 cents per kWh. The effective value of each stored kWh is the difference between what you would have paid at peak and what you would have earned from export — a net benefit of $0.20 to $0.44 per kWh. That is where the ROI case for batteries on APS becomes compelling.

SRP Solar Battery Storage Rates in 2026

SRP takes a fundamentally different approach to rate design. While SRP does offer time-of-use pricing, many of its plans also include demand charges — a separate fee based on your highest power draw in any single billing interval. This two-part pricing structure means batteries save SRP customers money through both TOU arbitrage and demand charge reduction.

SRP E-27 (Time-of-Use with Demand Charges)

The E-27 plan is SRP’s most popular TOU option for residential customers with solar. It features both time-differentiated energy charges and a demand component. The summer peak window runs from 2 PM to 8 PM on weekdays.

Summer off-peak: approximately $0.06 to $0.07/kWh
Summer on-peak: approximately $0.07 to $0.09/kWh (energy charge only)
Summer super-peak (2 PM to 5 PM or 5 PM to 8 PM, depending on season): approximately $0.25 to $0.35/kWh effective rate when demand charges are factored in
Winter off-peak: approximately $0.06 to $0.07/kWh
Winter on-peak: approximately $0.08 to $0.10/kWh
Demand charge: approximately $10.00 to $14.00 per kW of peak demand

The E-27 plan is where the math gets more complex but also more rewarding for battery owners. The energy-only TOU spread on E-27 is narrower than what APS offers on its aggressive plans. But the demand charge component adds a significant layer of savings potential.

Here is how it works: if your highest peak-hour grid draw in a given month is 6 kW (for example, your air conditioner and pool pump both running at the same time), your demand charge at $12.50/kW would be $75 for that billing cycle. A battery that can shave that peak down to 2 kW saves you $50 in demand charges alone — in a single month. Over the summer, demand charge reduction with a battery on the E-27 plan can save SRP customers $40 to $80 per month, on top of whatever TOU arbitrage savings the battery generates.

Combined TOU and demand charge savings on E-27 can reach $80 to $130 per month during the peak summer billing season for a household with a well-managed battery system.

SRP E-13 (Basic Residential Plan)

The E-13 plan is SRP’s standard residential rate without time-of-use differentiation. It charges a flat rate per kWh that varies by usage tier. Without a peak-to-off-peak spread, there is no TOU arbitrage opportunity, and without explicit demand charges in the traditional sense, the battery savings case is much weaker on this plan.

Most solar and battery owners on SRP should avoid the E-13 plan. If you are currently on E-13 and are considering battery storage, switching to E-27 before or at the time of installation is strongly recommended. The savings difference can be $500 or more per year.

SRP Customer Generation Plan

SRP’s Customer Generation plan is specifically designed for customers with solar panels. It features time-of-use pricing with a peak window and includes demand charges similar to E-27 but with rate structures adjusted for solar generation patterns.

Summer off-peak: approximately $0.06 to $0.07/kWh
Summer on-peak: approximately $0.08 to $0.10/kWh (energy charge)
Demand charge: approximately $10.50 to $13.50 per kW
Grid access charge: a fixed monthly fee in the range of $15 to $35 depending on system size

The Customer Generation plan can be advantageous for solar-plus-battery customers, particularly those with larger solar arrays. The key is that the demand charge component still provides significant savings potential with a battery, while the energy rates are competitive. However, the fixed grid access charge partially offsets savings for smaller systems.

Battery owners on this plan should focus on demand charge shaving as the primary savings lever. A battery that consistently keeps your peak grid draw under 2 to 3 kW can reduce demand charges by $40 to $70 per month during the summer, which more than offsets the fixed access charge.

SRP Export and Net Billing Rates

SRP offers a net billing structure for solar customers rather than traditional net metering. As of 2026, export credits are approximately $0.03 to $0.04/kWh for energy sent to the grid, which is even lower than APS export rates in some cases.

This makes the self-consumption argument for batteries equally strong on SRP. Every kWh you store and use yourself instead of exporting is worth the full retail rate you avoid paying, not the export credit you would have received.

APS vs. SRP: Side-by-Side Comparison for Battery Owners

Here is a summary comparing the two utilities across the metrics that matter most to battery storage owners.

Peak-to-off-peak spread (summer):

APS Saver Choice Max: $0.34 to $0.41/kWh
APS Saver Choice Plus: $0.23 to $0.28/kWh
SRP E-27 (energy only): $0.01 to $0.03/kWh
SRP E-27 (effective with demand): $0.19 to $0.29/kWh equivalent

Demand charges:

APS: None on residential TOU plans
SRP: $10.00 to $14.00 per kW on E-27 and Customer Generation

Export / net metering rate:

APS: $0.03 to $0.05/kWh
SRP: $0.03 to $0.04/kWh

Estimated monthly summer savings with battery (10-13.5 kWh system):

APS Saver Choice Max: $75 to $90+
APS Saver Choice Plus: $50 to $62
SRP E-27 with demand shaving: $80 to $130

Estimated annual savings with battery:

APS Saver Choice Max: $750 to $900
APS Saver Choice Plus: $500 to $650
SRP E-27: $700 to $1,100

Which Utility Is Better for Battery Storage ROI?

The answer depends on your usage patterns and how well you can manage peak demand.

SRP customers often see higher total savings because the demand charge reduction adds a second, powerful savings lever on top of TOU arbitrage. A battery that consistently shaves your demand peak can save $40 to $80 per month in demand charges alone, which is money APS customers simply do not have access to because APS does not use residential demand charges. When you add TOU energy savings on top, SRP battery owners on the E-27 plan can outperform even the most aggressive APS plan.

However, SRP savings are harder to maximize. Demand charges are based on your single worst interval in the billing period. One evening when your battery is depleted and your AC kicks into high gear can set a high demand peak that costs you for the entire month. Battery management on SRP requires more attention to system sizing and load management than on APS.

APS customers enjoy simpler, more predictable savings. The TOU arbitrage math on APS is straightforward: charge your battery during off-peak, discharge during peak, and the spread is your savings. There are no demand charges to worry about, and the savings are consistent day to day. APS Saver Choice Max offers the widest spread in Arizona, making it the single most lucrative plan for pure TOU arbitrage.

For most homeowners, the practical answer is this: you cannot choose your utility (it is determined by your address), so the better question is which rate plan on your utility gives you the best battery ROI. If you are on APS, move to Saver Choice Plus or Saver Choice Max. If you are on SRP, move to E-27 and invest in a battery system sized to shave your demand peaks.

Real-World Savings Example: A Phoenix Metro Household

Consider a typical 2,200-square-foot home in the Phoenix metro area with a 7 kW solar array and a 13.5 kWh battery system (such as a Tesla Powerwall 3 or Enphase IQ Battery 5P).

On APS Saver Choice Max:

Summer months (May through October): the battery discharges roughly 10 to 12 kWh during the 4 PM to 7 PM peak window each weekday. At a spread of $0.35 to $0.41/kWh, that is $3.50 to $4.92 per day, or roughly $77 to $108 per month.
Winter months (November through April): the spread narrows and usage drops. Expect $25 to $40 per month.
Annual total: approximately $750 to $900 in TOU arbitrage savings.

On SRP E-27:

Summer months: TOU arbitrage saves roughly $20 to $35 per month (the energy-only spread is narrower). But demand charge reduction saves an additional $50 to $75 per month by keeping peak demand below 2 to 3 kW instead of the 5 to 7 kW typical without a battery.
Winter months: demand charges are lower but still present. Expect $20 to $35 per month combined savings.
Annual total: approximately $700 to $1,100 in combined savings.

With a net battery cost of $8,500 to $10,000 after the 30% federal tax credit, both scenarios deliver a payback period of roughly 8 to 12 years, with SRP customers on E-27 potentially reaching payback faster if they are diligent about demand management.

Tips to Maximize Battery Savings on Either Utility

Regardless of whether you are on APS or SRP, these strategies help you get the most out of your battery investment.

Size your battery to cover the full peak window. On APS, the summer peak is 3 hours (4 PM to 7 PM). A 13.5 kWh battery can typically cover this if your peak-hour usage is under 4 to 4.5 kW sustained. On SRP, the peak window is longer (2 PM to 8 PM), which may require a larger battery or a second unit for full coverage.

Pre-cool your home before peak hours. Set your thermostat to 74 to 76 degrees by 3:30 PM, then let it drift up to 78 to 80 during peak. This dramatically reduces your AC draw during the hours your battery is discharging and extends battery life through the full peak window.

Use smart scheduling for large loads. Run your pool pump, dishwasher, laundry, and EV charger during off-peak hours. On APS, that means after 7 PM or before 4 PM. On SRP E-27, avoid running any large appliance during the 2 PM to 8 PM window.

Monitor demand peaks on SRP. If you are on the E-27 plan, use your battery’s app or a home energy monitor to track your peak demand in real time. One slip-up — running the dryer and AC simultaneously while the battery is depleted — can set a demand peak that costs you for the entire billing cycle.

Consider grid charging during monsoon season. Arizona’s monsoon season (June through September) brings clouds that reduce solar production. Many battery systems allow you to charge from the grid during off-peak hours at $0.06 to $0.07/kWh and then discharge at peak rates. Even without solar, the spread still generates meaningful savings.

Get Matched With a Battery Installer Who Knows Your Utility

The best battery ROI comes from working with an installer who understands your specific utility’s rate plans and can size and program your system accordingly. A battery optimized for APS Saver Choice Max requires different settings than one optimized for SRP E-27 demand charge shaving.

Browse vetted battery installers in your Arizona city to find local professionals who specialize in solar battery storage and know the ins and outs of APS and SRP rate optimization. You can also review the full cost breakdown for solar battery systems in Arizona to understand what you should expect to pay before requesting quotes.

Bottom Line: APS vs. SRP for Battery Storage in 2026

Both APS and SRP offer rate structures that make home battery storage financially viable in 2026. APS gives you a simpler path to savings through wide TOU spreads, with Saver Choice Max delivering the highest per-kWh arbitrage value in the state. SRP offers potentially higher total savings through the combination of TOU rates and demand charge reduction, but requires more careful system management.

No matter which utility you are on, the low export rates both utilities pay for excess solar make the case for battery storage stronger than ever. Storing your solar energy and using it during peak hours is worth five to ten times more than sending it back to the grid. A properly sized battery system on the right rate plan can save you $600 to $1,100 per year, pay for itself in under a decade, and provide backup power during Arizona’s increasingly common extreme heat events and monsoon outages.

The first step is understanding your current rate plan and usage patterns. The second step is talking to a qualified installer who can model your specific savings. Find a battery installer near you and start that conversation today.