Is the EcoFlow DELTA Pro Ultra or the Anker SOLIX F3800 Plus better for whole-home backup?

The DELTA Pro Ultra is the bigger system and the better answer if you want one box to carry a whole house: 6,144Wh of storage, 7,200W of output, and 5.6kW of solar input in a single stack, with 120V and 240V so a well pump, water heater, or central AC can start. The Anker SOLIX F3800 Plus is the better value if your goal is to carry the circuits that matter — fridge, furnace fan, Wi-Fi, a couple of rooms — for roughly half the price of the equivalent EcoFlow kit. Both are split-phase systems that expand with extra batteries, so start with the loads you must keep on, not with the brand.

Do these backup kits run central air conditioning?

Both are 120V/240V split-phase systems, which is the prerequisite for running a central air handler and condenser, but the deciding factor is the surge draw of your specific unit and how long you expect to run it. The DELTA Pro Ultra's 7,200W of continuous output gives it the most headroom for a compressor start. A 3-ton central AC can eat a battery of this size in a few hours, so plan on cooling one zone rather than the whole house, and confirm your compressor's locked-rotor amps against the kit's surge rating on the product page before you buy.

How much solar do I need to keep a backup kit charged during a multi-day outage?

Enough to replace what you use each day. If your essential loads draw 5kWh a day and you get four good solar hours, roughly 1,200-1,500W of panel gets you back to even, allowing for weather and angle losses. The DELTA Pro Ultra accepts up to 5.6kW of solar input, so it can refill a mostly drained battery in one strong day; smaller kits recharge slower and lean more on topping up from the grid before a storm arrives.

Does a backup power kit qualify for the federal solar tax credit?

Not for the homeowner credit that used to apply. The Section 25D residential clean energy credit was repealed for systems placed in service after December 31, 2025, so a 2026 purchase of a portable or plug-in solar generator does not carry that 30% credit. Some state and utility storage incentives still exist and vary widely. Check the IRS guidance and DSIRE for your state, and confirm with a tax professional before you count on any credit.

EcoFlow DELTA Pro Ultra vs Anker SOLIX F3800 Plus (2026)

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The moment you start pricing whole-home backup, you run into a gap that’s hard to explain: two kits that both promise to keep your house running, and one costs more than twice the other. The Anker SOLIX F3800 Plus Smart Home Backup Power Kit is listed at $3,499.99. The EcoFlow DELTA Pro Ultra Smart Home Solar Kit is $7,769.00.

That gap isn’t marketing. It buys specific things — more stored energy, more output, far more solar input — and whether those things matter depends entirely on what you’re trying to keep alive when the grid drops. Here’s the honest comparison.

The short answer

Buy the F3800 Plus if you want split-phase home backup at the lowest entry price and your outage plan is “keep the fridge, the furnace fan, the well pump, the Wi-Fi, and a few rooms running.” Buy the DELTA Pro Ultra if you want a single system with enough capacity and solar input to run most of a house through a multi-day outage without rationing — and you’re willing to pay roughly double for the headroom.

Head to head

Kit	Platform	Price	Buy
Anker SOLIX F3800 Plus Smart Home Backup Power Kit	Split-phase 120V/240V · stackable expansion batteries · 5.0 rating (15 reviews)	$3,499.99	Check price →
EcoFlow DELTA Pro Ultra Smart Home Solar Kit	6,144Wh · 7,200W · 5.6kW solar input · 120V/240V · 5.0 rating (32 reviews), #1 seller in kits	$7,769.00	Check price →

Prices are as listed at the time of writing and move with sales — the product pages are the source of truth, and the 10% code applies at checkout.

Where the extra money actually goes

1. Stored energy: how many hours you get

The DELTA Pro Ultra holds 6,144Wh in its base configuration. In practical terms, a modern fridge, a gas furnace’s blower, LED lighting, phones, laptops, and a Wi-Fi router together pull somewhere around 3–6kWh over a full day, so one charge covers roughly a day to a day and a half of genuine essentials — longer if you’re disciplined, much shorter the moment you add anything with a heating element.

The F3800 Plus starts smaller. That’s the trade you’re making at half the price, and it’s a fair one for most households: the second day of an outage is usually when a solar array or a grid recharge window shows up anyway. Anker’s expansion batteries let you buy capacity later, once you’ve lived through an outage and know what you actually ran — which is a better way to spend the money than guessing high on day one. The product page carries the current capacity and expansion figures; confirm them against your must-run list before you order.

2. Output: what will actually start

Both kits are split-phase, delivering 120V and 240V. That matters more than most buyers realize. A well pump, an electric water heater, an electric range, and a central AC condenser are all 240V loads — a 120V-only power station simply cannot run them no matter how big its battery is. If any of those are on your must-run list, split-phase is not optional, and both of these kits clear that bar.

Where they differ is headroom. The DELTA Pro Ultra’s 7,200W of continuous output absorbs a compressor start or a well pump kicking on while the microwave is running. With less headroom you sequence your loads instead — run the pump, then the microwave, not both.

3. Solar input: whether it refills mid-outage

This is the least-discussed spec and the one that decides a multi-day outage. A battery that can’t recharge is a countdown timer. The DELTA Pro Ultra accepts up to 5.6kW of solar input, enough to take a mostly drained system back to full in a single strong day. That turns a one-day battery into an indefinite one as long as the sun comes up.

If you’re going the smaller route, budget for panels separately and plan for a slower refill. Our portable solar panel comparison covers what 200W to 400W of portable panel actually delivers in real conditions.

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Which one fits your house

Choose the Anker SOLIX F3800 Plus if:

Your must-run list is essentials plus one or two 240V loads (well pump, water heater)
Outages in your area last hours to a couple of days, not a week
You’d rather start at $3,499.99 and add expansion batteries once you know your real usage
You want split-phase capability without the whole-house price tag

Choose the EcoFlow DELTA Pro Ultra if:

You want to run most of the house, not a chosen subset of circuits
Someone in the home depends on power — medical equipment, or heat and cooling in a climate where losing them is dangerous
Multi-day outages are normal where you live, so the 5.6kW solar input is the point
You want the whole thing solved in one purchase

▶ See the DELTA Pro Ultra Smart Home Kit code CHADPENFOLD — 10% off

What neither kit replaces

Neither of these is rooftop solar, and neither should be confused with it. A grid-tied rooftop array shuts down the instant the grid fails — anti-islanding rules require it — so a house with panels and no storage is just as dark as one without. If you’re weighing a full rooftop install against a backup kit, the honest answer is that they solve different problems: rooftop solar cuts your bill, a backup kit keeps you running. Our state-by-state solar guides break down installed costs and what incentives survive in 2026.

The other thing worth saying plainly: the federal Section 25D credit that used to cover 30% of a residential solar and storage purchase was repealed for systems placed in service after December 31, 2025. Don’t build a 2026 budget around it. State and utility storage incentives still exist in places — check DSIRE for yours and confirm anything tax-related with a professional.

The pick

For most homes, the F3800 Plus is the smarter first purchase. Half the price gets you the split-phase capability that actually separates home backup from a camping battery, and you can grow it. Step up to the DELTA Pro Ultra when the loads you can’t lose are big, the outages are long, or the solar input is the whole reason you’re buying.

▶ Buy the Anker SOLIX F3800 Plus — $3,499.99 code CHADPENFOLD — 10% off

▶ Buy the EcoFlow DELTA Pro Ultra — $7,769.00 code CHADPENFOLD — 10% off

Keep reading: EcoFlow DELTA Pro Ultra kits compared · Best portable solar panels · Solar backup power guides by state