Off-Grid Communications and Backup Power Starter Plan
Match backup power to your actual devices: phones, radios, lights, fans, laptops, CPAP machines.
Quick answer
What size backup power do I need for an outage?
List your must-run devices and add their watt-hours: a phone charge is about 15 Wh, a laptop 60 Wh, a CPAP night 100 to 400 Wh depending on settings. A 300 Wh power station covers phones and lights for days. Medical devices and fridges push you toward 1,500 Wh or more plus solar.
Device Runtime Calculator + Charging Priority Sheet
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Start with a device inventory, not a product page
Backup power buying goes wrong in one of two directions: a cute battery that dies the first night, or a $3,000 unit for a household that needed phone charging. The fix is a 10-minute inventory.
Write down what must run in an outage, for how many hours a day. Phones, router, lights, a fan, the CPAP, maybe the fridge. That list, not the marketing page, sets your size.
Watts versus watt-hours, in plain words
Watts measure how hard a device pulls right now. Watt-hours measure how much a battery holds. A 60-watt fan running 5 hours uses 300 watt-hours. That one sentence is most of the math.
Real batteries deliver about 85 percent of their label after conversion losses, so pad your total by 20 percent. The worksheet in the download does this for you.
- 1List each must-run device and its watts (check the label or brick).
- 2Multiply watts by hours per day for each device.
- 3Add them up, then add 20 percent for losses.
- 4That number, per day, is the battery size to shop for.
The charging hierarchy
Order beats size. Phones first, always: they are light, news, and your link to help. Then lights, then the router if service survives, then fans or heat support, then the fridge in bursts (an hour on, a few off, door shut).
Post the order on the battery. Under stress, nobody does math.
Solar panels: placement is everything
A 100-watt panel makes about 400 to 500 watt-hours on a clear day, angled at the sun, and a fraction of that flat in the shade. Chase the sun across the day, tilt the panel, and keep the glass clean.
Panels through a window lose most of their output. Outside placement with the cable through a cracked window beats a window-side lean every time.
Generator safety, the short version
Gas generators make cheap watts and deadly air. Outside only, 20 feet or more from windows, doors, and vents, exhaust pointed away, with a battery carbon monoxide alarm inside the house. Refuel only after the engine cools.
Battery power stations exist exactly because those rules are hard at 2 a.m. in the rain. Silent, indoor-safe, no fuel. For phone-and-light households they are simply the better tool.
Never run a generator indoors, in a garage, or near openings. Carbon monoxide is odorless and kills fast.
The 72-hour communications plan
When cell service degrades, texts go through jams better than calls. Have one out-of-area contact everyone texts. Add a battery or crank NOAA weather radio for one-way news when the network fails completely.
Write the plan on paper: contact numbers, radio channel notes, and the charging order. Paper needs no watts.
The product pack for this guide
Each pick maps to a checklist line above. Read the when-to-skip note before buying: the fastest way to waste money on preparedness is buying gear for a problem you already solved.
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Grid Doctor 300 Solar Generator System
My Patriot Supply
- Best fit
- Phones, lights, router, and small devices for days
- Why it helps
- Roughly 300 watt-hours with solar recharge: the honest size for a household whose list is phones, lights, and a fan.
- When not to buy
- Fridges and most CPAP-plus-humidifier setups exceed it. Run the worksheet before deciding.
Grid Doctor 3300 Solar Generator System
My Patriot Supply
- Best fit
- Medical devices, fridge bursts, and work-from-home continuity
- Why it helps
- Capacity in the multi-thousand watt-hour class turns a multi-day outage into an inconvenience instead of an evacuation.
- When not to buy
- If your must-run total is under 500 watt-hours a day, this is paying for capacity you will never touch.
65W Power Bank with 15W Solar Panel
My Patriot Supply
- Best fit
- The per-person phone layer under any bigger system
- Why it helps
- Keeps phones off the big battery entirely, which stretches the power station for the loads that actually need it.
- When not to buy
- Drawer full of charged power banks already? Skip. Count what you own first.
Go deeper
Backup Power Pro System
You will buy exactly the backup power your devices need, run it in the right order, and never wake up to a dead battery at 2 a.m.
- Watts, watt-hours, and the one equation that sizes everything
- The device inventory, with worked examples for three household types
- Battery stations versus generators versus both: decision tables
- Solar reality: placement, angles, clouds, and winter
Common questions
How many watt-hours does a CPAP use per night?
Without the humidifier and heated hose, many machines draw 30 to 60 watts: roughly 250 to 500 watt-hours over a full night. Turning off the humidifier is the single biggest saving on battery. Check your model label.
Can a power station run my fridge?
In bursts, sometimes: a modern fridge uses 1 to 2 kilowatt-hours a day, so even big units run it hours, not days. The smarter play is cycling: an hour on, several off, door closed. For continuous fridge power you want a generator or a very large battery plus solar.
Do solar panels work on cloudy days?
They work at 10 to 30 percent of rated output, roughly. Plan on solar as a slow trickle in bad weather and size the battery to bridge 2 cloudy days.
Is a gas generator or battery station better?
Different jobs. Gas wins on raw watts per dollar and long runtimes, but demands outdoor operation, fuel storage, and noise tolerance. Batteries win on safety, silence, and indoor use. Many prepared homes end with a small battery now and a generator later.
Sources this guide leans on
Planning information, not professional medical, legal, or engineering advice. In any life-threatening situation, call 911 first.
Keep building
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