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Fast, Reliable Solar Battery Storage & Backup Across Fontana
Solar battery storage in Fontana runs $9,500 to $18,500 for a full installation, and most homeowners we work with get it done in one to two days once the permit clears. If you’re at the end of your rope with SCE’s time-of-use rates or you want backup power for the blackouts that hit the 92336 foothills during Santa Ana wind events, call us at (877) 550-6892. We are Gus’s Solar, and we have been installing battery systems in Fontana long enough to know that this city has heat and dust problems that no coastal installer ever accounts for.
Why Gus’s Solar Is Fontana’s Preferred Solar Battery Storage & Backup Company
We run a different kind of shop. Gus Petrakis founded this company in 2011, put his own name on the truck, and still answers his own phone. That matters in Fontana, where homeowners have been burned by door-to-door crews who quoted a battery system from a brochure and then disappeared the morning after the check cleared. Gus does not do that. He gives you the year-25 production estimate off your actual utility bill, not the day-one number. And if something is not right, the 90-Day Done Right Promise means one call brings him back, in writing, on every job.
Fontana is not like Torrance or Rancho Cucamonga. It sits against the San Gabriel mountain wall, which traps smog and Mojave dust. Summer highs hit 105 to 112 degrees in the inland thermal trough. We size batteries here differently than we would for a coastal SCE customer, because the heat derates panels, throttles cabinet-installed batteries, and changes how a system actually performs on an August afternoon. Our Solar Battery Storage & Backup team has seen all of it.
- Live person answers 24/7: Not a voicemail. Not a call center in another state. You call, a person picks up.
- Owner-operated since 2011: Gus’s license number is published. His address is published. His name is on the building. If something goes wrong, you know who to call.
- Background-checked, uniformed crew: Gus’s own team does the install. No subcontracted labor. You know who is on your property before they arrive.
- No-hassle upfront pricing: Bring me a bill, I’ll bring you the math. The price quoted is the price charged.
Our Solar Battery Storage & Backup Services in Fontana
Tesla Powerwall Installation
A Tesla Powerwall installed in Fontana runs $13,000 to $18,500 including gateway, wiring, and labor. We install these often in 92336, where the larger master-planned homes have the wall space and the panel capacity to support two or three units. One thing we flag on every Powerwall quote here: west-facing garage walls in Fontana catch brutal afternoon sun. If your garage lacks ventilation, the battery’s thermal management system works harder, and you will see throttling on 108-degree days. We will move the install to a cooler location or add airflow before we mount it. Most Powerwall installs in Fontana take one day on site after the permit is issued.

Enphase IQ Battery Installation
Enphase IQ Battery systems in Fontana typically run $9,500 to $14,000 for a single 5P unit with the System Controller. These are the batteries we recommend most often for the older flatland homes in 92334 and 92335, because the modular design lets you stagger capacity as your needs grow. Enphase batteries also handle the Fontana heat better than some competitors, with a wider operating temperature range. We retrofitted one on a 2004 Spanish S-tile home in northern Fontana’s 92336, where Fontana Building & Safety had already flagged the 100-amp panel. We coordinated the $3,200 panel upgrade before interconnection, then wired the battery for NEM 3.0 time-of-use so the homeowner could shift the 105°F afternoon load off the grid and still charge from their existing SunPower array.

Whole-Home Backup Power
Whole-home backup in Fontana means sizing for air conditioning, because from June through September the AC runs hard from 3 PM to 9 PM. A single battery will not carry a 4-ton AC unit through a five-hour outage. We will tell you that directly. Most Fontana homes in 92336 need two or three batteries for true whole-home coverage, which puts the project in the $22,000 to $38,000 range before any tax credit. If that is more than you need, we will tell you that too, and we will show you exactly which circuits a single battery can protect: refrigerator, lights, medical equipment, garage door opener, Wi-Fi, and select outlets. No pressure. Take two weeks. Think about it. The price will be the same.

Battery Retrofit for Existing Solar
We do a lot of retrofit work in Fontana because the city has tens of thousands of solar systems that went in before batteries became standard. Most retrofits here run $10,000 to $16,000, depending on whether your existing inverter can be AC-coupled or needs component replacement. The 1950s and 1970s tract homes in 92334 and 92335 frequently have 100-amp service panels that cannot pass interconnection once a battery is added. That panel upgrade, typically $2,500 to $4,000, catches out-of-area sales reps who quote the job remotely without pulling permit history. We pull permit history before we quote. That is the difference between an honest number and a surprise line item.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Fontana
We work with Tesla, Enphase, FranklinWH, and SolarEdge. We stock common breakers, gateway components, and battery firmware tools locally, which means a firmware failure in Fontana does not sit in queue for three weeks waiting on a factory technician. Tesla and Enphase are the two we install most in this city. FranklinWH is worth a look if you want whole-home coverage without the Tesla price tag. We will give you straight answers on all of them, including which ones handle Fontana’s summer heat without throttling Fontana homeowners should not have to discover through a phone app at 6 PM on a 110-degree day.
Common Solar Battery Storage & Backup Problems We See in Fontana Homes
- Thermal derating and throttling. Ambient heat in the inland trough reduces battery round-trip efficiency by 5 to 12 percent compared to coastal installs. Tesla Powerwalls on west-facing garage walls are the worst offenders; we reposition or add ventilation when we see it.
- Dust-coated panels undercharging batteries. Mojave winds push particulate against the mountain wall, and Fontana panels collect it faster than Ontario or Rancho Cucamonga. A dirty array produces 8 to 15 percent less, which means your battery starts the evening undercharged right when you need it most.
- Undersized 100-amp panels. Homes built in the 1950s through 1970s in 92334 and 92335 frequently cannot pass interconnection with battery backup. Fontana Building & Safety flags this on permit review, and the $2,500 to $4,000 upgrade catches homeowners who bought from an out-of-area quote mill.
- Batteries draining too fast on hot evenings. When the AC runs from 4 PM to 9 PM because Fontana holds heat late into the evening, a single battery depletes in two to three hours. We see this constantly. The fix is accurate load sizing from the start, not buying more battery later.
Pricing for Solar Battery Storage & Backup in Fontana, CA
A single Enphase IQ Battery 5P installed in Fontana runs $9,500 to $12,000. A Tesla Powerwall 3 with gateway runs $13,000 to $16,500. Add a second battery, and the equipment cost drops per unit, but labor and wiring stay the same. Whole-home backup on a large 92336 home with two AC units typically lands between $25,000 and $38,000. If your home needs a panel upgrade from 100 amps to 200 amps, add $2,500 to $4,000. These are the numbers we quote, built from your actual utility bill and your actual home, not a generic brochure estimate. Call (877) 550-6892 for a free estimate. If a salesman needs an answer tonight, the answer is no. We do not work that way.
We Also Serve Cities Near Fontana
Besides Fontana, we regularly install solar battery storage in Bloomington, Rialto, Glen Avon, and Pedley. Each of these communities shares the same inland thermal trough and mountain-front dust conditions, but permit requirements and panel ages differ street by street. We pull the permit history for every address before we quote. Call (877) 550-6892 to schedule a site visit.
Serving Fontana, CA - Our Local Coverage Area
We’re based in the Fontana area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Solar Battery Storage & Backup in Fontana
In Fontana, panels lose 8 to 15 percent of production to dust and smog accumulation without regular cleaning, which can translate to 30 to 60 minutes of lost battery charging time each afternoon. The mountain wall traps Mojave particulate against the city, and the 92334 and 92335 flatlands catch the worst of it. Annual cleaning is not optional here. It is a measurable production decision. Call (877) 550-6892 and we will tell you whether your array is undercharging your battery.
Yes, in most cases. Fontana Building & Safety regularly flags 100-amp panels as insufficient for grid-tied solar with battery backup during permit review. The upgrade to 200 amps runs $2,500 to $4,000, and it is a line item that out-of-area sales reps miss because they never pulled your permit history. We pull it before we quote, so the number you get is the number you pay.
Yes. Fontana’s inland thermal trough runs 10 to 15 degrees hotter than SCE’s coastal territory, and that heat cuts battery round-trip efficiency by roughly 5 to 12 percent. Cabinet-installed batteries on west-facing garage walls are most affected. We account for this when we size your system, and we position batteries where they will not sit in direct afternoon sun. A Fontana install is not the same as a Torrance install, and the math should not be either.
Yes. Time-of-use and NEM 3.0 optimization programs a battery to discharge during the 4 PM to 9 PM window, when SCE rates peak and your air conditioner is doing its heaviest work. The battery charges from solar during midday, then carries you through the expensive evening hours while still reserving a backup percentage for outages. We set this up on nearly every Fontana install because the math is obvious here. Call (877) 550-6892 for the exact numbers on your bill.
The most common causes are dust accumulation cutting panel output, heat derating on older panels, and an undersized array that was originally sized for net metering, not battery charging. Fontana’s soiling effect plus the thermal trough means a system that produced 10 MWh a year in 2018 might now produce 8.5 MWh without cleaning. We diagnose this before quoting a battery, so you do not buy storage capacity your array cannot fill. Free second opinion on any written estimate from another company.
Call Gus’s Solar for Battery Storage in Fontana
Solar battery storage is not a one-size-fits-all purchase in Fontana. The heat, the dust, the mountain wall, and the aged panel infrastructure all change the math. Gus Petrakis has been doing this since 2011, and he will give you the year-25 numbers off your actual bill, not the day-one brochure figure. Bring me a bill, I’ll bring you the math. Take two weeks. Think about it. The price will be the same. Call (877) 550-6892 for a free estimate, and a live person will answer, day or night.
Written by Gus Petrakis, Owner at Gus’s Solar, serving Fontana since 2011.






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