The verdict: the Jackery HomePower 3600 Plus is the unit for a cold-climate home with a gas furnace, for outages that run two days or more, and for a household with a medical device that cannot go down. Its 3,584Wh and 3,600W carry the essentials plus a furnace blower through a winter night on their own; expansion to 21kWh carries them for days; and a transfer switch wires it to the furnace circuit. If your outages last a day and your list is the fridge, Wi-Fi, and lights, buy the HomePower 3000. If anything on your list needs 240V, a well pump or central AC, you need the Solar Generator 5000 Plus.
The rest of this page shows the working, so you can check it against your own house before you spend anything.
What expansion to 21kWh actually buys
The base unit is a 3,584Wh LiFePO4 battery with 3,600W of AC output on 120V outlets. On its own it behaves much like the HomePower 3000: one to two days of essentials, or one winter night of essentials plus a furnace. The difference is what happens next. The HomePower 3000 stops there. The 3600 Plus accepts added battery packs up to 21kWh, and every pack turns hours into days.
The table shows each load on the base battery, per 1,000Wh of added packs, and at the full 21kWh. The middle column is per 1,000Wh rather than per pack because pack sizes and bundles change; check the product page for what is offered today. Every runtime is on battery alone with no sun and nothing else plugged in.
| Load | Typical draw | Energy used | On 3,584Wh alone | With added battery packs | At 21kWh |
|---|---|---|---|---|---|
| Refrigerator or fridge-freezer | ~150W running | 1,000 to 1,500Wh a day | 2 to 3 days | Each 1,000Wh adds most of a day | Two to three weeks |
| Chest freezer | ~100W running | 600 to 900Wh a day | 4 to 6 days | Each 1,000Wh adds more than a day | Three weeks and more |
| Wi-Fi router and modem | ~10W | ~240Wh a day | About two weeks | Each 1,000Wh adds four days | Months |
| Ten LED bulbs | ~50W | 50Wh an hour | About 70 hours | Each 1,000Wh adds 20 hours | Weeks of evenings |
| Phones and a laptop | ~20 to 60W | 150 to 300Wh a day | 12 to 24 days | Each 1,000Wh adds 3 to 6 days | Months |
| CPAP (no heated humidifier) | 30 to 60W | 300 to 500Wh a night | 7 to 12 nights | Each 1,000Wh adds 2 to 3 nights | Six weeks and more |
| Gas furnace blower and ignition | 400 to 600W running | 3,000 to 5,000Wh a day in deep cold | 17 hours to a day | Each 1,000Wh adds 5 to 8 hours | 4 to 7 days |
| Small window AC | 400 to 600W | 4,000 to 8,000Wh a day | 11 to 21 hours | Each 1,000Wh adds 3 to 6 hours | 2.5 to 5 days |
| Sump pump (1/3 hp) | ~800W running, higher to start | Depends on the rain | Starts it; ~130Wh per ten minutes | Each 1,000Wh adds 75 minutes of pumping | Any storm |
| Electric space heater | 1,500W | 1,500Wh an hour | About two and a half hours. Do not plan on it | Each 1,000Wh adds 40 minutes | About 14 hours |
| Well pump | ~1,000W running, 2 to 3x to start | 240V | No. Needs 240V | No | No |
| Central AC | 3,000 to 4,000W, big surge | 240V | No. Needs 240V and 7,200W | No | No |
Two lines carry the whole argument. The furnace line shows why the base unit is not enough on its own in January: a furnace in deep cold uses most of 3,584Wh in a day, and the fridge and lights want the rest. The 21kWh column shows what the expansion is for: four to seven days of furnace, or three days of furnace plus everything else. The space heater line is the same warning as on every battery: 1,500W drains 3,584Wh in about two and a half hours. Let the furnace heat the house.
▶ See the HomePower 3600 Plus, expandable to 21kWh
The transfer switch and hardwired circuits
The second thing you pay for is that the 3600 Plus is transfer-switch ready. This matters because the load that decides a winter outage, the furnace, has no plug; it is wired straight into the panel. Without a transfer switch, a battery can run the fridge on an extension cord and cannot touch the furnace at all.
A transfer switch sits beside your breaker panel and lets the 3600 Plus feed a chosen handful of circuits directly. For most cold-climate homes that is the furnace, the fridge, and the kitchen and hallway lights. When the grid drops, you flip the switch and those circuits come back on, with no cords across the floor. The same switch can feed a sump pump circuit, the load that decides a spring outage.
Two rules, and neither has an exception. It must be fitted by a licensed electrician, who will size it to your panel and your local code. Never backfeed a wall outlet with a cord from the unit; it can energise the line outside your house and kill the worker fixing it, and it is illegal almost everywhere.
Plan the switch and the expansion together. A furnace circuit on a base battery is a one-night solution; on an expanded battery it is what gets a house through a storm.
Three days without the grid, in winter
Here is a three-day January outage for a house with a gas furnace, a fridge, a few lights, Wi-Fi, phones, and a CPAP, with the furnace and fridge on the transfer switch and the thermostat turned down to 60°F to stretch the battery.
Evening one. The power drops at 6 p.m. with the temperature outside in single digits. The furnace comes back on through the switch. The first night costs about 3,400Wh: roughly 2,000Wh for the furnace over twelve hours in deep cold, 600Wh for the fridge, 200Wh for four hours of lights, 120Wh for Wi-Fi, 100Wh of phone charging, and 400Wh for the CPAP.
On the base 3,584Wh unit, that is the outage. You wake on morning two with a few hundred watt-hours, a grey sky, and a choice between the fridge and the furnace. That is the honest limit of the unit on its own in deep cold, and why the 3600 Plus without expansion is a HomePower 3000 with a better upgrade path.
Days two and three, on the expanded unit. Each full day of furnace, fridge, lights, Wi-Fi, phones, and CPAP costs about 6,000Wh at a 60°F thermostat in deep cold. Three days is roughly 18,000Wh. At the full 21kWh you finish evening three with about 3,000Wh in hand and no sun at all, a fourth night of furnace and fridge if the crews are late. A system expanded partway lands between those two pictures; every 1,000Wh of packs is about four hours of the whole house.
Solar recharge, honestly
On a bright summer day, with the panels angled at the sun and moved once or twice to follow it, expect to put back 1,500 to 2,000Wh. That is most of a day’s essentials, which is why a summer outage can run for several days on this unit even without expansion. On a grey winter day, expect a few hundred watt-hours. That keeps the router and the phones going, not the furnace, and in the three-day picture above it is the margin, not the plan.
Treat those as a rough range; panel wattage, latitude, cloud, and shade all shift the number. Charge to full from the grid before a forecast storm, and set the panels out first thing in the morning. For a cold-climate buyer the rule is to size the battery for the outage and treat the sun as a bonus, which is the whole case for expansion packs over more panels.
Still 120V, and what that rules out
The 3600 Plus delivers 3,600W on 120V only. That is enough for every ordinary plug-in appliance and for the furnace, but it draws a hard line through the rest of the house.
- No well pump. A well pump draws about 1,000W running and two to three times that to start, on 240V. If you are on a well, read our well pump guide and start at the Solar Generator 5000 Plus.
- No central AC or heat pump. Central AC draws 3,000 to 4,000W with a large surge and needs 240V and a 7,200W unit. The 3600 Plus will run a small window AC for a room.
- No electric water heater and no electric dryer. Both are 240V loads.
If the appliance is on a double breaker in your panel, this is not the unit for it. A house with one 240V must-have has to size up to the 5000 Plus, which delivers 7,200W on 120V and 240V and expands to 60kWh.
3600 Plus vs HomePower 3000 vs 5000 Plus
The three Jackery home units solve three sizes of the same problem. Here is how they line up.
| Unit | Capacity / output | Best for | Buy |
|---|---|---|---|
| Jackery HomePower 3600 Plus (this review) | 3,584Wh · 3,600W · expandable to 21kWh · transfer-switch ready · 120V | Essentials plus a furnace blower or window AC, multi-day outages | Check price → |
| Jackery HomePower 3000 | 3,072Wh · 3,600W · panels included · 120V · not expandable | Fridge, Wi-Fi, lights, phones, CPAP for 1 to 2 days | Check price → |
| Jackery Solar Generator 5000 Plus | 5,040Wh · 7,200W · 120V/240V · expandable to 60kWh | Well pump, central AC, water heater, hardwired circuits | Check price → |
The HomePower 3000 is the unit to weigh against this one if you are not sure you need expansion. It is a little smaller at 3,072Wh with the same 3,600W, the bundle includes solar panels, it runs indoors at about 30 decibels with zero exhaust, and it costs less. Our HomePower 3000 review walks a two-day outage through it hour by hour. What it cannot do is grow or feed a furnace circuit.
The 5000 Plus is a different category. 5,040Wh, 7,200W, both 120V and 240V, and expansion to 60kWh is what a well pump, central AC, or an electric water heater need. If any of those is on your list, the 3600 Plus was never the answer. Our full comparison of the three works through each.
Who should buy it, and who should not
Buy the HomePower 3600 Plus if:
- You heat with a gas furnace and your winters are the kind where an outage is dangerous. Our North Dakota, Wisconsin, and Alaska guides all land on this unit with expansion packs.
- Your last outage ran past two days, or your utility’s do.
- Someone in the house depends on a CPAP, an oxygen concentrator, or a powered medical fridge, and one night of runtime is not an acceptable plan.
- You want the furnace, fridge, and lights back on through a transfer switch, and room to add capacity later.
Buy something else if:
- Your outages last a day and your list is the fridge, Wi-Fi, lights, and phones. That is the HomePower 3000, with panels included, for less money.
- Anything on your list runs on 240V: a well pump, central AC, a heat pump, an electric water heater, an electric dryer. That is the Solar Generator 5000 Plus, and nothing smaller.
- You plan to buy the base unit and never expand it. Then the HomePower 3000 does nearly the same job for less, and the premium buys nothing you will use.
Our best solar generators for home backup guide sets all three against the Anker and EcoFlow kits, and the state-by-state backup guides size each unit against your own state’s outages.
Where to buy
The HomePower 3600 Plus sells direct from Jackery. Prices move with Jackery’s promotions, so check the product page for today’s price, and price the expansion packs at the same time; it is a multi-day unit only once they are on it. A promotion can close the gap between this unit and the HomePower 3000, so look at both before you settle.
▶ Shop the HomePower 3600 Plus direct from Jackery
▶ See current Jackery deals before you buy
Keep reading: Best solar generators for home backup · HomePower 3000 review · HomePower 3000 vs 3600 Plus vs 5000 Plus · North Dakota outage guide · Backup power guides for every state