Deep planning
301 A month of restoration
Plan for a month while services come back. Household power versus small DC power, and enough battery sense to not hook the wrong things together.
A month while things are being restored
301 is not “live in the woods.” It is the stretch where the crew is working, the store is open some days, the water may be on a boil notice, and the power comes and goes. A month of that is a different problem than a week of closed roads.
You still are not studying one kind of disaster. A broken grid, a ruined water plant, or a long repair after a storm can all look like this. The response is the same shape: keep the household oriented, keep small power honest, and do not improvise electrical work you do not understand.
AC: power for the house
Alternating current is what the outlets in the wall already speak. Fridge, freezer, well pump, window air conditioner, a normal lamp. Making those work without the utility is generator territory, or a large inverter fed by a serious battery bank. Both can run the house. Both can be installed wrong.
If a generator is part of your plan, treat carbon monoxide as the first fact, not the footnote. CDC: never run a generator inside the home or the garage, even with the doors and windows open. Use it outside, more than 20 feet from windows, doors, and vents. Have a battery-powered CO alarm in the house, because you cannot see or smell the gas.
- Do not backfeed the house by plugging a generator into a dryer outlet or a suicide cord. That can energize lines outside and hurt the people repairing them. A transfer switch or interlock, put in by someone who does that work, is the safe way to feed a panel.
- Do not heat with a gas oven. Ready.gov warns that this raises the risk of carbon monoxide, fire, and burns.
- Decide which AC loads earn the fuel. Air conditioning in a Florida month can matter for health. A second refrigerator full of drinks does not.
DC: phones, lights, and other small loads
Direct current is the quiet half of a long outage. It will not run the air conditioner. It will keep a phone charged, an LED light on, and a radio alive. For a month of restoration, that is often the difference between “we can cope” and “we are lost after dark.”
- USB is a 5-volt world. Phones, many LED lamps, and small fans already live there. Use the charger or the 12-volt-socket adapter made for that device.
- A lot of LED work lights and camping lights are built for 5 volts (USB) or for 12 volts. Read the label. “It has two wires” is not a specification.
- The ordinary safe path is boring: car running outdoors, or a power station used the way its manual says, then a USB adapter, then the phone or the light.
- Do not idle a car in a garage to charge phones. The same carbon monoxide rule applies. Outdoors, away from the house, or not at all.
Keep DC and AC separate in your head. A month goes better when the phone and the flashlight do not depend on the generator starting.
Battery education
A battery is not a bucket of generic electricity. The chemistry decides the charger, the voltage, and what happens if you get it wrong. This is the short version. It is not a wiring class.
| Lead-acid | Lithium | |
|---|---|---|
| What people mean | Car starting batteries, and deep-cycle batteries made to be drained and recharged. | Phone and laptop packs, most “power stations,” and LiFePO4 house batteries. Those lithium types are not the same as each other. |
| What it is for | A car battery is a short burst to start an engine. Using it as the house battery all night can leave you unable to leave. A deep-cycle battery is the one built for a slow drain. | Steady power for electronics. Larger packs can carry a small house load if they were built for that and you follow the manual. |
| Charging | Use a lead-acid charger. Charging gives off hydrogen. Do it where air moves. No sparks, no closed trunk, no pit. | Use a charger made for that exact lithium chemistry. A lead-acid charger can overcharge a lithium pack. LiFePO4 is not “any lithium.” |
| A clue people miss | A “12-volt” lead-acid battery and a “12-volt” LiFePO4 battery are close enough in voltage to fool you. Close is not compatible. | |
Testing. A multimeter tells you voltage. Voltage is a clue, not a health report. A weak battery can read “full” and then collapse when a light or a pump actually draws current. If you do not know how to test under load, do not parallel a mystery battery onto a good one to “share the work.”
What is safe to hook together
When two batteries or a battery and a device share wire, sameness is the safety rule.
- Reasonable: same chemistry, same voltage, similar age and size, polarity you have checked twice, a fuse on the positive wire, and a device that was built for that voltage.
- Not reasonable: lead-acid posts tied to a lithium pack. Old and new batteries in series. A swollen, leaking, or hot pack. USB gadgets spliced onto a battery with speaker wire. Jumper cables from a car onto a power station because “it’s all 12 volts.”
If the label and the manual disagree with a friend at the hardware store, believe the label. If you cannot find the label, do not invent the chemistry.