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Russel,

Thats fine, and will likely work for you, just remember though, that Car batteries are not made to be fully discharged. They are designed to pretty much always remain topped off, and are made for outputting a large amount of amperage, in a short period of time, to turn the starter. Also, they are flooded batteries, never meant to be turned on their side or upside down. Keep this in mind, and you should be fine. I wouldn't take one below 50% charge, or else your plates may start to oxidise, reducing the life of the battery.

stevie_d_64 wrote: 2 fans, at night, to keep the air moving in our bedroom...

1 surge protector/power strip to keep our cell phones charged up (overnight)

And on that power strip, I would still like to be able to run the laptop on power and to keep the batteries on this thing peaked...

So.. first you'll need to find the wattage requirements of the fans. This is harder than it sounds. Consumer electronics are required to be rated to the MAX amount they will ever pull. Since these fans are AC motors, the rating on them will more then likely be their start-up surge rating, not their running rating. If you have a current clamp to measure how much its using while running, that's the best way, or even plugging it into one of those kill-a-watt things will work too.

My guess is that a standard box fan, on high, would pull maybe 100-150W, once its running. On start-up, however, it could easily hit a few hundred more watts.

Cell phone chargers etc are usually like <50W each.
A typical Laptop charger is ~100 watts.

Generators:
You could probably do fine with a small 750-1000W Generator.

As far as reliable generators, Personally, I've always seen good results with Honda ones.
No-name ones sometimes are name-brand motors, re-branded, but sometimes they are just that, no-name brands.
Briggs and Stratton, I would consider about mid-range for generator usage. I wouldn't consider one for any sort of long-term use though.

Also, Home generators require frequent maintenance. Most people completely skip this fact, and this is why they break down.

Generally, oil changes on generators are required a lot more often they you would think. Most of them recommend an oil change after the first few hours of operation (sometimes ~5-10) , then another one after another, smaller then usual number (~50-100) , and then finally you get to a repeating number, usually a few hundred hours. (~100-400) depending on generator

Another Option would be 100% Solar!:

Buy and store some large multi-hundred watt solar panels. Then, once the storm hits, and you're out of power, mount and use the solar panels to charge a few large 12VDC Deep Cycle Batteries during the day, and use them to run some 12VDC Fans at night.

Required matereals: I'd say 2 or 3 100 Watt Panels, A solar Controller, and some batteries. There are batteries specifically made for Solar Power usage, that are designed to be frequently charged and discharged.
Benefits: It's Completely Silent, requires no fuel, and very little maintenance :)

Ill see about getting some links to local Texas sources of solar solutions.


Personally, I am looking into getting a backup standby generator for my home, that runs on natural gas.
We were out of power for 3 weeks after the Hurricane. I eventually got a nice 3000W Generator, wired it into my electrical panel, and powered most of my house with it (just no AC) but the first 2 weeks definitely was not fun.

Sorry, yea, I saw "AC Power Supply" and Immediately thought 'oh, he wants a power supply for his AC!' My bad
Probably because it's not ever called an 'AC power supply' when you make AC from a DC source, but rather, an AC Inverter :)
Totally my fault for assuming wrongly haha
Now I feel like an idiot... even though What I said was correct, He wasn't talking about Air Conditioning... Doh!

But yea, for powering things like cell phone chargers, etc. a battery or two, plus a small inverter will be fine

Basically, just add up all the things you'll want to power simultaneously, most of the plug-in transformers have a max wattage or amperage rating on them.

I'm gonna go crawl back into a hole now

A car battery will power consumer electronics devices (Cell phones, laptops, etc) for a VERY long time.

Its even more efficient, however, if you get 'car chargers' which use the DC directly instead of having to use AC though. Making AC from DC, You typically lose 20% or so on the inversion, then you'll lose another 10-20% on each wall-wart/plug in transformer to convert it back to DC. Thats a lot of lost power to convert DC->AC->DC again.

flb_78 wrote:Cig lighter inverter will be fine. Just make sure the load you're pulling through isn't too high for the inverter.

Ok. I'll interject here. Quick Quals: Military Trained Electronics & Electrical Systems expert. Do Generator and Solar power systems for TxDot, HCTRA, and Houston Metro on almost a daily basis (If you've seen solar trailers, or RF sites out there anywhere in Houston, chances are I was involved with it in one way or another). So I deal with Solar, AC-DC Rectification, and DC-AC Inversion on a daily basis :) Anyways, lets get started.

First Issue - Starting Current.

Depending on the size of the AC, you might not find an inverter large enough. An AC Compressor can pull up to 10x it's running current during startup. That is why home AC units usually have their own 30 or 40 amp breaker.

If you're bringing a wall unit, or portable AC unit, be prepared to have to supply 10-15 amps @120VAC for startup, then it will settle down to a nicer 2-3A running.

10 Amps at 120VAC, with an inverter running at 85% efficiency (which is a high estimate btw) will require 1411 Watts just to start the thing.

So, you'll need a 1500W inverter, minimum. More then likely, you will actually need a 2000W.

Second Issue - AC Motor

Since the compressor is an actual AC Motor, you WILL need a true Sine Wave Inverter. AC Motors WILL NOT run on the Square Waves generated by your typical inverter. It will cause nothing but problems. True Sine Wave inverters are $$$ compared to your cheap-o square wave ones. I'm not going to dive down into the electrical theory of a single phase AC motor vs 3 phase vs DC vs etc etc. But Trust me on this. Your Cheap Home Depot Brand 1500W inverter will just destroy the compressor of an AC unit, if it starts at all.

EDIT: Here's the cheapest 2000W True Sine Wave inverter I could find:
http://www.invertersrus.com/sk2000-112.html" onclick="window.open(this.href);return false;

The BETTER option is to find a 12VDC Air Conditioner. They exist, mostly in a roof-mount setup, for RV's and such, but I have seen them in standalone. These use a DC motor, and will not require any inversion, and therefore, no efficiency loss!!

EDIT #2: I'm an idiot. He wasn't talking about air conditioning! Doh! Well, I'll leave this here in case anyone ever searches about Building Mobile Air Conditioning! LOL