Do You Need Whole-Home Backup? Smart Load Shedding Math

It is 6 p.m. on a July evening, and the grid just dropped across a whole subdivision. One homeowner spent on a 30 kWh whole-home battery array. Three doors down, a neighbor has a 15 kWh battery and a Smart Panel. An hour later, both homes still have cold refrigerators, lights, and a charging phone. The difference is not battery size. It is what each home decided not to run.

Conventional wisdom gives you two choices: a small battery for essentials, or a big, expensive one for whole-home backup. Both cost more than they need to, because both treat the battery as the only lever. There is a third option almost no buyer's guide explains: an electrical panel that acts as a home energy command center and controls what the battery has to power in the first place.

Here are the questions this guide answers:

• What smart load shedding actually is, and how it works during an outage
• How many kWh it takes to run AC, a dryer, and an EV charger during a blackout
• Whether you need whole-home backup, or whether partial is enough
• How long a 10 kWh or 20 kWh battery really lasts, with the heavy loads on and off
• What a smart panel does that a regular panel cannot, and what it costs

Key takeaways

• A central air conditioner draws 3-4 kW running and surges to several times that draw on compressor startup, so an unmanaged 20 kWh battery running AC alone lasts only about 5-6 hours (Trane HVAC electrical data; Lennox AC wattage; verified 2026-06-27) [5][13].
• Smart load shedding, the automatic pausing of heavy circuits like AC, EV chargers, and electric dryers during an outage, can extend a 15-20 kWh battery from 2-4 hours to an estimated 14-20 hours of essential-load runtime (load assumptions from ENERGY STAR / DOE appliance data; illustrative; verified 2026-06-27) [5][13][15].
• The U.S. residential electricity price averaged 17.3 cents/kWh in 2025, and California averaged 32.54 cents/kWh, making every kWh of usable backup capacity more valuable in high-rate states (EIA, 2025; verified 2026-06-27) [1].
• The Kora Smart Panel controls up to 12 circuits at up to 60 A each, including circuits heavy enough for HVAC, EV charging, and electric dryers, the exact loads that most rapidly drain a backup battery (Kora Power tech specs; verified 2026-06-27) [4].
• The U.S. average home uses about 29 kWh of electricity per day, but during an outage a home's true priorities (refrigeration, lights, Wi-Fi, a medical device) often draw about 1.0-1.5 kW combined, roughly a tenth to a fifth of full daily demand, so smart load management serves what matters on far less power (EIA RECS for daily use [3]; ENERGY STAR / DOE appliance data for essential loads [15]; verified 2026-06-27).

What Is Smart Load Shedding and How Does It Work During an Outage?

Smart load shedding is the automatic pausing or throttling of high-draw electrical circuits during a grid outage, so a home battery can stretch its stored energy toward the loads that matter most. Instead of letting an air conditioner or EV charger drain the battery in hours, a smart panel pauses those circuits and keeps essentials running far longer. The intelligence layer, not the battery, decides.

The old approach is a critical-loads subpanel: a fixed list of circuits wired at install, where the AC is either always backed up or always out. A smart panel sheds and restores loads dynamically instead. The Kora Smart Panel monitors battery state of charge in real time across its 12 controllable circuits [4]; when the battery drops below a threshold you set, low-priority circuits (EV charger, dryer, second-zone AC) pause automatically, then return when solar recharges it. When the grid fails, it switches to backup in under 10 milliseconds [4].

A battery stores energy. A smart panel decides what deserves it.

You see all of this in the Kora app: the Circuits Management view shows which circuits are live, which are paused, and how much reserve is left, so you are never guessing in the dark. That visibility turns a black box into a decision you control.

So the question you have been asking, "how big a battery do I need?", is the wrong one. The better question is whether your panel is smart enough to make a mid-size battery behave like a much bigger one.

What Appliances Use the Most Power During an Outage?

A handful of appliances dominate your entire backup budget. Central air conditioning, the electric dryer, the EV charger, and the electric water heater are the Big Four, each drawing several kilowatts. Everything else, the refrigerator, lights, fans, router, and a medical device, adds up to roughly 1 kW combined. That gap is the whole game.

Air conditioning alone accounts for about 19% of U.S. home electricity consumption, per the EIA's 2020 Residential Energy Consumption Survey [2]. The split lands in two clear tiers. The Big Four heavy loads each draw several kilowatts:

• Central AC: 3-4 kW running, per Trane, with a full system over 3,500 W per Lennox [5][13], and on startup it briefly pulls several times that, a 5-7x spike a soft starter can cut by up to 70% [14].
• Electric dryer: 3-5 kW [15].
• Level 2 EV charger: 7.2-11.5 kW under the SAE J1772 standard [6][15].
• Electric water heater: 4.5-5.5 kW [15].

Stack the first three and you have added 15-20 kW of demand to a battery that holds only 15-20 kWh.

Shed the AC, the dryer, and the EV charger. What's left draws under 1.5 kW, and your battery suddenly lasts all night.

The other tier is tiny, the essentials under 1.5 kW combined [15]:

• Refrigerator: 100-200 W.
• LED lighting: ten fixtures under 200 W combined.
• Wi-Fi router: around 10 W.
• CPAP: 30-60 W without a heated humidifier.

Add phone charging and you are still under 1.5 kW for the whole house, a 5-to-8x swing in kilowatts versus running everything, and the same swing in runtime.

Shedding just three circuits cuts your backup load by roughly 12-20 kW, so your battery lasts 5-10x longer.

Source: central AC running watts from Trane HVAC electrical data [5] and Lennox AC wattage [13]; compressor startup multiple and soft-start reduction from HVAC soft-start engineering data [14]; dryer, water heater, refrigerator, lighting, router, and CPAP watts from ENERGY STAR / U.S. DOE appliance-energy data [15]; EV charger from SAE J1772 Level 2 EVSE standard [6]. Verified 2026-06-27.

During Kora setup, a licensed electrician assigns each circuit a priority tier with your input, and the app shows each circuit's live draw so you see exactly where your kilowatts go. (Panel work is electrician territory, never DIY.) The takeaway: the heavy loads are the budget, and a smart panel lets you spend it on purpose.

Interactive

How Many kWh Does It Take to Run AC During a Power Outage?

Running central air conditioning during an outage takes roughly 24-32 kWh per day for a typical unit running about 8 hours, based on a 3-4 kW draw [5][13]. So a 20 kWh battery powering only the AC would be exhausted in about 5-6 hours. By a wide margin, AC is the single load most likely to drain a backup battery before sunrise.

The exact number varies with tonnage, runtime hours, and heat, but the direction is never in doubt: a compressor is the heaviest steady load most homes have. On startup it briefly draws several times its running watts, so the inverter must be sized for the surge, not just the steady draw, and a soft starter can cut that inrush by up to 70% [14].

This is where smart load management rewrites the math. Instead of running AC flat-out all night, the Kora Smart Panel can schedule it into a backup cycle, on during the hottest afternoon hours, off overnight, so the battery covers comfort without a compressor running 24 hours straight. (You set the rules; it is scheduling, not a guarantee.) The Kora Powerblocks inverter is rated 11.4 kW continuous and 18 kW peak, built for residential compressor starts [4].

A 20 kWh battery runs AC alone for about 5 hours. Cycle the same AC with a smart panel, and the battery covers comfort and essentials into the next day.

Solar changes the equation again. As an illustrative assumption, a 6 kW array producing six usable hours can replenish 20-30 kWh in a single sunny afternoon (6 kW x 6 h, derated), often more than a managed home draws overnight, stretching a one-day outage into multi-day territory. Production varies by array, location, and weather; the DOE/NREL PVWatts tool models site-specific output [16]. For why July outages cluster at 6 p.m., see our summer 2026 grid blackout prep guide.

One caveat every honest sizing guide should print: runtime depends on unit size, runtime hours, solar input, battery state of charge, and load settings, so these are illustrative scenarios from published appliance data, not guaranteed performance. The point for your home is that AC does not have to be all-or-nothing, and a smart panel gives you the middle setting.

Do You Need Whole-Home Battery Backup, or Can You Get By With Partial Backup?

For most homeowners, you do not need brute-force whole-home backup, because a smart-panel-managed mid-size battery (10-20 kWh) covers your real outage priorities at a fraction of the cost. The U.S. average residential outage lasted 11 hours in 2024, and in normal years it is closer to two hours [7]. A well-managed 15-20 kWh battery covers that window comfortably.

There are really three strategies, not two:

• Brute-force whole-home backup covers your entire main panel at full demand, needing a large battery (25-40+ kWh) and budget.
• Traditional critical-loads panel wires a short, fixed list of essentials, cheaper but rigid.
• Smart load management is the one missing from almost every buyer's guide: a smart panel backs up most or all circuits but prioritizes them dynamically, shedding heavy loads when reserves fall and restoring them when solar recharges.

A mid-size battery does not run your full instantaneous demand. It runs your priorities, intelligently.

The question is not small battery or big battery. It is whether your panel knows which loads deserve the battery.

A smart-panel-managed mid-size battery covers most homes' real outage needs at roughly half the cost of brute-force whole-home sizing.

Source: NREL solar-plus-storage installation cost benchmarks [12]; EnergySage installer cost baseline (seller-affiliated) [8]; Kora Power tech specs [4]. Cost ranges are illustrative and vary by site, labor, and configuration. Verified 2026-06-27.

Who genuinely needs true whole-home backup? Homes with electric heating in cold climates (a heat pump cannot be shed), well pumps, medical equipment that tolerates no interruption, or homeowners who want zero management. For everyone else, the Kora Founders Edition, Smart Panel plus Powerblocks, is built for this middle path: circuit-level control that makes a mid-size battery act like a whole-home system. Whether that beats a generator is covered in our home battery vs. generator guide.

What Is the Difference Between a Critical Loads Panel and a Smart Panel?

A critical loads panel is a fixed subpanel wired at install to feed backup power to a short list of pre-selected circuits, while a smart panel controls every connected circuit with a digital switch and real-time metering, adjusting priorities in software instead of by rewiring. The critical loads panel offers simplicity and lower cost; the smart panel, flexibility and visibility. One is a wiring decision. The other is a software decision.

The critical loads panel has no intelligence: it connects the backup source to whatever circuits an electrician chose on install day. Want to add the home office next year, or drop the guest-room AC? That means a rewire. It cannot reason about battery state of charge, time of day, or which load matters most right now.

A smart panel gives every circuit a digital switch plus live metering, with priorities living in firmware and the app. The Kora Smart Panel controls up to 12 circuits at up to 60 A each, supports 200 A max grid input, is UL67 subpanel listed, communicates over Wi-Fi, Bluetooth, 4G, and Ethernet, and carries a 12-year warranty [4]. Change a circuit's priority in the app, not with a truck roll.

A critical loads panel is a wiring decision made once. A smart panel is a priority decision you can change any evening from your phone.

Smart panels are a small but growing category. Panels from SPAN, which lists 16-48 controllable circuits depending on model [9], and Lumin add circuit-level control to an existing battery. The Kora Smart Panel is purpose-built to integrate directly with Powerblocks as one system, with shared firmware and the Kora app as the single interface, rather than a panel bolted onto someone else's battery. That design philosophy is why we call it the command center of an integrated home energy system.

One non-negotiable, regardless of brand: panel and backup installation must be done by a licensed electrician, with a permit required in most jurisdictions, and Kora does not support DIY panel work. A smart panel future-proofs your priorities: the day you add a medical device or a new EV, you reprioritize in software, not copper.

How Does a Smart Panel Decide Which Circuits Stay On During an Outage?

A smart panel decides which circuits stay on by following priority tiers set during commissioning, then watching battery state of charge in real time. Tier 1 (always on): refrigerator, CPAP, lights, router. Tier 2 (on while the battery is above your threshold): one HVAC zone and select outlets. Tier 3 (shed at outage start or when reserves dip): EV charger, dryer, pool pump, second HVAC zone. The logic runs automatically, the moment the grid drops.

A licensed electrician sets these tiers with your input, and the thresholds are configurable, not baked in. As the battery discharges, the Kora Smart Panel compares state of charge against your thresholds and pauses or restores circuits accordingly; when solar climbs the battery back above a threshold, it can restore lower-priority circuits automatically, then shed them again as evening approaches. You are not babysitting a battery; the system routes power the way a thermostat routes heat.

Your home's energy command center treats a power outage not as an emergency but as a routing problem, and it solved it before you noticed the lights blink.

You keep the final say. Through the Kora app you can manually override any circuit, turning the dryer on for one cycle, with the battery consequence and remaining-runtime estimate shown right there so you decide with eyes open [4].

One compliance note: actual runtime depends on loads, solar, battery state of charge, and ambient conditions, and individual figures require a site-specific load analysis. What you can count on is the behavior, not a guaranteed number of hours, with the decision-making happening on its own and you stepping in only when you want to.

What Can a Smart Electrical Panel Do That a Regular Panel Cannot?

A smart electrical panel can meter every circuit in real time, switch any circuit on or off remotely, set priority tiers, and automatically shed or restore loads based on battery reserve and time of day, all from an app. A regular panel does none of that. The difference is intelligence and control, not capacity.

A conventional 200 A panel is a fuse board with no opinions: it distributes power and protects wiring from overcurrent, and that is the whole job. It cannot tell you the dryer is drawing 4.8 kW, turn the EV charger off when reserves run low, or make decisions during an outage. A breaker reacts to a fault; it never reasons about priorities. Every choice it "makes" was made by an electrician on install day and frozen in copper.

A smart panel adds a digital switch and current sensor to every circuit, then wraps them in software, unlocking four capabilities a regular panel structurally cannot offer: per-circuit visibility, remote control, priority logic, and automated load shedding. The Kora Smart Panel does all four across its 12 controllable circuits and surfaces every reading in the Kora app [4]. You stop guessing which breaker feeds what.

A regular panel distributes power and protects wires. A smart panel decides, in real time, which loads deserve the power you have left.

The payoff shows up on two different days. On a normal day, per-circuit metering and automated load shifting pull heavy loads off peak-rate windows, the core of TOU savings in high-rate states. On an outage day, that same control collapses backup demand from 11 kW to under 1.5 kW [4][15]. A regular panel asks an electrician to predict your future once; a smart panel lets you change your mind any evening, from your phone.

How Long Will a 10 kWh or 20 kWh Battery Last During an Outage?

A 20 kWh battery lasts roughly 5 hours powering a full home with the AC running, and as little as 2 hours if you add an EV charger, but the same battery lasts an estimated 13-20 hours when a smart panel sheds the heavy circuits and serves only essentials at about 1.0-1.5 kW [5][13][15]. The battery does not change. The panel does. That is the whole thesis of this article.

Walk through the scenarios:

1. Scenario A, no load shedding (20 kWh): AC at 3.5 kW plus fridge, lights, and Wi-Fi totals roughly 4.0 kW, for about 5 hours; add a 7.2 kW EV charger and you drop to under 2 hours.
2. Scenario B, smart panel active (20 kWh): shed the AC, EV charger, and dryer, and the remaining essentials draw 1.0-1.5 kW, for an estimated 13-20 hours.
3. Scenario C, smart shed plus solar (15 kWh): an outage starting at 8 p.m. is covered overnight at ~1.2 kW, and the next day, as an illustrative assumption, six hours of solar at 6 kW (derated) generates 25-30 kWh, far more than the night used, so the system keeps running [16].

The gap between Scenario A and Scenario B on the identical 20 kWh battery is where most buyers get sizing wrong: roughly 5 hours versus 13-20, with nothing about chemistry, inverter, or capacity changed, only whether a panel sheds the AC, dryer, and EV charger. And recovery matters: a battery that refills from solar each afternoon turns a one-night reserve into open-ended resilience, exactly what Scenario C models.

The same 15 kWh battery that empties in 2 hours backing up the whole house can power the essentials for 14 hours. The battery did not change. The panel did.

The same 20 kWh battery lasts about 2 hours under full home load, or up to 18 hours when a smart panel sheds the heavy circuits.

Source: appliance wattage from Trane HVAC electrical data [5], Lennox AC wattage [13], and ENERGY STAR / U.S. DOE appliance-energy data [15]; solar recharge modeled with DOE/NREL PVWatts assumptions [16]; runtime = battery kWh ÷ active kW (simplified). Runtime estimates are illustrative based on published appliance data; actual runtime depends on battery state of charge, temperature, solar input, and site-specific loads. Verified 2026-06-27.

This is the data every top-ranking page refuses to show you. The Kora Powerblocks line scales from 8 kWh (a 2-module tower) to 28 kWh (a 7-module tower), up to 112 kWh across four towers, so the 10-20 kWh sweet spot here is just 3-5 modules in one tower [4]. So pick the battery for how long you want the essentials to last, then let the panel stretch that capacity.

Can a Mid-Size Home Battery Back Up a Whole House With a Smart Panel?

Yes, a mid-size home battery (10-20 kWh) can back up a whole house with a smart panel, with one honest qualification: it cannot run the house at full instantaneous demand, but it does not need to. It runs the house's priorities, intelligently, and for most homes those draw under 2 kW, well within what a 15-20 kWh battery covers for 10+ hours.

Define "whole house" the way you live in it during an outage: not the pool pump or dryer through a 12-hour blackout, but refrigeration, a medical device, one zone of climate control, lighting, Wi-Fi, and phone charging. That bundle is the real definition of whole-home coverage for the hours that count, and a smart-panel-managed mid-size battery delivers it.

One engineering requirement is worth naming: even carrying just 1.5 kW of steady load, the inverter must absorb a surge when a heavy circuit wakes up, like an AC compressor restarting. The Kora Powerblocks inverter handles 11.4 kW continuous and 18 kW peak, switches to backup in under 10 milliseconds, and its LFP cells are rated for 6,000+ cycles at 80% capacity [4]. That headroom lets AC cycle without tripping the system.

A mid-size battery cannot run everything at once. With a smart panel, it does not have to, it runs everything that matters, intelligently.

When do you need more battery? An all-electric home in a cold climate with an essential heat pump, multi-day outages with no solar, or medical equipment that tolerates no interruption. The scaling path is open: start with one Kora Powerblocks tower (8-28 kWh) and add towers later, up to four and 112 kWh, while the Smart Panel stays the same [4]. You grow the battery, not the brain, buying right-sized today and scaling only if your loads genuinely demand it.

How Much Does Whole-Home Battery Backup Cost Compared to Partial Backup?

Brute-force whole-home battery backup typically runs $30,000-$50,000+ installed, a traditional critical-loads partial system runs about $10,000-$18,000, and a smart-panel-managed mid-size system lands between at roughly $15,000-$28,000, while covering the same practical priorities as the brute-force option [8][12]. The difference between the top and middle tiers is mostly software and circuit intelligence, not raw battery capacity.

That flips the usual logic. A $15,000-$28,000 smart-panel system can serve the same real outage priorities as a $40,000+ brute-force array, because the panel sheds the loads the big battery was paying to power anyway. You buy intelligence instead of buying your way out of the sizing problem with kilowatt-hours. (Wondering whether a battery pencils out at all? Start with our are home batteries worth it in 2026 primer.)

Buy intelligence, not kilowatt-hours: a smart panel sheds the loads the big, expensive battery was paying to power anyway.

Now the part every cost guide must get right in 2026: the federal 25C/25D residential energy tax credits expired December 31, 2025, under the One, Big, Beautiful Bill Act. Per the IRS, the 25C Energy Efficient Home Improvement Credit is not allowed for property placed in service after that date, and the 25D Residential Clean Energy Credit is not allowed for expenditures made after it, so no 30% federal credit applies to battery systems installed in 2026 (verified 2026-06-27) [10]. Any source still citing a 30% federal battery credit for 2026 is stale. State and utility incentives vary; California's SGIP may offer rebates, but its budget and step-downs shift, so verify current program status before counting on a figure [11].

Smart load management delivers whole-home priorities at a fraction of brute-force whole-home cost, and no federal credit applies to 2026 battery installs.

Source: cost ranges from NREL solar-plus-storage benchmarks [12] and EnergySage installer baseline (seller-affiliated) [8]; federal 25C/25D credit expired 2025-12-31 under the One, Big, Beautiful Bill Act, per the IRS [10]; California SGIP status varies [11]. Costs are illustrative and vary by site. Verified 2026-06-27.

One more lens on value: California residential electricity averaged 32.54 cents/kWh in 2025, versus a 17.3-cent U.S. average, with many Californians facing higher marginal time-of-use rates [1]. Under California's NEM 3.0 net-metering rules, exported solar earns far less than it once did, making storing and self-consuming your own kilowatt-hours the better play. The more your power costs, the more every usable kWh of backup is worth, during an outage and on the 360 normal days a battery shifts load off peak, where the economics get more interesting still, see making money selling power back to the grid (Kora Energy Trading is a planned feature, so treat it as market backdrop, not a current Kora payout). For current pricing, check korapower.com/products/founders-edition. The bottom line: intelligence is cheaper than capacity.

See what the Kora 4-in-1 system costs for your home → Reserve your Founders Edition. A licensed electrician should run a site load analysis before sizing any system.

Frequently Asked Questions

What size battery do I need to back up a 2,000 sq ft house?

It depends on what you back up, not square footage. At full-home draw (4-6 kW with central AC running), a 20 kWh battery lasts about 3-5 hours. With smart load shedding cutting draw to 1-2 kW, the same 20 kWh lasts 10-20 hours [5][13][15]. The right answer always starts with a load analysis by a licensed electrician.

Can you run central air conditioning on a home battery?

Yes, with caveats. A central AC draws 3-4 kW running and surges to several times that draw on compressor startup, so your inverter must handle the surge; a soft starter cuts the inrush sharply [5][14]. A 20 kWh battery running only AC at about 3.5 kW lasts roughly 5-6 hours. Smart load management can cycle AC on and off to preserve battery for essentials, extending overall runtime.

What is the difference between a smart panel and a critical loads panel?

A critical loads panel is a fixed subpanel wired at install to feed backup power to pre-selected circuits, with no flexibility. A smart panel controls every circuit with a digital switch and adjusts priorities dynamically in software and an app [4]. Smart panels offer flexibility and visibility; critical loads panels offer simplicity and lower hardware cost.

Is whole-home battery backup worth it?

For most homeowners, whose outages run under 24 hours, a smart-panel-managed mid-size battery (10-20 kWh) delivers whole-home practical coverage at lower cost than brute-force whole-home sizing [7][8][12]. True whole-home backup is worth it for all-electric homes in cold climates, homes with well pumps, or homeowners who want zero management during an outage.

How does the Kora Smart Panel manage circuits during an outage?

The Kora Smart Panel assigns priority tiers to up to 12 circuits during commissioning by a licensed electrician. When the grid fails, the system switches to backup power in under 10 milliseconds, and low-priority circuits (EV charger, dryer) are shed to protect battery reserve [4]. You can monitor and override any circuit in real time through the Kora app.

A battery stores energy. A smart panel decides what deserves it, and that single shift lets a mid-size 10-20 kWh battery back up your whole home's real priorities for the hours that count, without paying for a whole-house array you do not need. There is no one-size-fits-all answer, only the right load analysis for your home and rate plan.

See what the Kora 4-in-1 system costs for your home → Reserve your Founders Edition.

Battery backup and smart panel installation requires a licensed electrician and permits in most jurisdictions. Contact a qualified installer for a site load analysis before sizing your system. Runtime figures in this article are illustrative scenarios based on published appliance data and are not guaranteed.

Related Articles

• Home Battery vs. Generator: The Complete 2026 Buyer's Guide
• Summer 2026 Grid Blackout Prep
• Are Home Batteries Worth It in 2026?
• Can You Really Make Money Selling Power Back to the Grid? The 2026 Math

References

1. U.S. Energy Information Administration (EIA). Retail Sales of Electricity, Residential (2025): U.S. average 17.3 cents/kWh; California 32.54 cents/kWh. Retrieved via EIA API, data period 2025, verified 2026-06-27. https://www.eia.gov/electricity/data.php ↩
2. U.S. Energy Information Administration (EIA). Frequently Asked Questions: How much electricity is used for air conditioning? (2020 RECS data; air conditioning ~19%, or 254 billion kWh, of U.S. home electricity consumption). Verified 2026-06-27. https://www.eia.gov/tools/faqs/faq.php?id=1174&t=1 ↩
3. U.S. Energy Information Administration (EIA). Residential Energy Consumption Survey (RECS) (aggregate household consumption baseline; U.S. average home ~29 kWh/day). Verified 2026-06-27. https://www.eia.gov/consumption/residential/ ↩
4. Kora Power. Founders Edition Tech Specs (canonical): Smart Panel 12 circuits at up to 60 A, 200 A max grid input, UL67 listed, Wi-Fi/Bluetooth/4G/Ethernet, 12-year warranty; Powerblocks 11.4 kW continuous / 18 kW peak, <10 ms switchover, 4 kWh modules, 8-112 kWh, 6,000+ cycles at 80% capacity. https://korapower.com/pages/tech-specs-founders-edition ↩
5. Trane. Understanding Amperage, Voltage, and Watts in HVAC (manufacturer engineering reference; a central AC unit typically uses between 3,000 and 4,000 W and 15-45 amps at ~240 V). Verified 2026-06-27. https://www.trane.com/residential/en/resources/blog/hvac-amperage-voltage-and-watts/ ↩
6. SAE International. J1772 Electric Vehicle Conductive Charge Coupler (Level 2 EVSE, 7.2-11.5 kW). https://www.sae.org/standards/content/j1772_201710/ ↩
7. U.S. Energy Information Administration (EIA). Hurricanes in 2024 led to most hours without power in 10 years (U.S. average 11-hour outage in 2024). https://www.eia.gov/todayinenergy/detail.php?id=66744 ↩
8. EnergySage. Energy Storage / Home Battery Cost (seller-affiliated installer cost baseline). https://www.energysage.com/energy-storage/ ↩
9. SPAN. SPAN Smart Electrical Panel (16-48 controllable circuits depending on model; up to 200 A service). Verified 2026-06-27. https://www.span.io/panel ↩
10. Internal Revenue Service (IRS). One, Big, Beautiful Bill Act provisions (primary source): the 25C Energy Efficient Home Improvement Credit is not allowed for property placed in service after Dec. 31, 2025, and the 25D Residential Clean Energy Credit is not allowed for expenditures made after Dec. 31, 2025. Verified 2026-06-27. https://www.irs.gov/newsroom/one-big-beautiful-bill-provisions ; IRS, Residential Clean Energy Credit, https://www.irs.gov/credits-deductions/residential-clean-energy-credit ↩
11. California Self-Generation Incentive Program (SGIP). Program status and step funding (verify current step before citing figures). https://www.selfgenca.com/ ↩
12. National Renewable Energy Laboratory (NREL). U.S. Solar-Plus-Storage Installation Cost Benchmark. https://www.nrel.gov/solar/market-research-analysis/solar-installed-system-cost.html ↩
13. Lennox. Air Conditioner Wattage: What You Need to Know (manufacturer reference; a typical central AC may use roughly 2,000-5,000 W, and a full-sized central system can draw over 3,500 W). Verified 2026-06-27. https://www.lennox.com/residential/lennox-life/consumer/air-conditioner-wattage ↩
14. Arlington Air Conditioning & Heating. What Is a Soft Start Air Conditioner? Inrush Current Mitigation & LRA Analysis (HVAC engineering reference; a compressor can draw 5-7 times its running current at startup, and a soft starter can mitigate that inrush by up to 70%). Verified 2026-06-27. https://www.arlingtonairconditioningheating.com/what-is-a-soft-start-air-conditioner/ ↩
15. ENERGY STAR / U.S. Department of Energy. Estimating Appliance and Home Electronic Energy Use and ENERGY STAR product categories (per-appliance energy reference: standard electric water heater elements rated ~4,500 W on 240 V; electric clothes dryers ~3,000-5,000 W resistive; refrigerators cycle at ~100-200 W; Wi-Fi routers ~10 W; CPAP 30-60 W without heated humidifier; LED fixtures well under 200 W combined). Verified 2026-06-27. https://www.energy.gov/energysaver/estimating-appliance-and-home-electronic-energy-use ; https://www.energystar.gov/products/clothes_dryers ; https://www.energystar.gov/products/water_heaters ↩
16. U.S. Department of Energy / National Renewable Energy Laboratory (NREL). PVWatts Calculator (site-specific solar production modeling). Verified 2026-06-27. https://pvwatts.nrel.gov/ ↩