Now that it's officially hurricane season, we've been thinking about investing in a generator. But this backup battery looks like it might be an interesting solution. It's also got a fifteen hundred watt voltage inverter built in, so it looks like you could use your car as a quiet gasoline generator.

Just buying an inverter for the car is probably cheaper. I have a 750 W inverter that's a bit bigger than a cigar box. It's intended as ultimate backup for the basement freezer or for the furnace in the event of an extended power outage.

Always be aware of your current-drain vs. run-time when using a battery bank, Rand. That backup battery appears to be designed for high current/short-run applications, but would last depending on the current drain you put on it.

RV's are designed with power requirements in mind when "dry-camping"; "house" batteries can and will run most of the RV's lighting, gas-appliance ignition and fresh-water systems for a couple days of very judicious use, but can't power high-current equipment like the air conditioner or long-term use of other a.c. devices like the TV due to current draw and ineffeciencies in the inversion process - which is why most motorhomes are also equipped with a gas, diesel or propane generator.

Also, before relying on a vehicle to recharge a battery bank or operate devices through an inverter, it would be VERY wise to replace the vehicle's stock-grade alternator with a beefier one (many cities have alternator dealers that can either rebuild your stock unit to higher amperage output or sell you an upgraded alternator to fit the vehicle. Let the dealer know what you're doing and why - you'll usually get free advice and tips on keeping your alternator in good condition). Almost all alternators on current vehicles are designed to supply little more than the nomimal charging level for the vehicle battery, NOT the level required to charge a battery bank AND operate the vehicle systems.

Here's hoping for a fairly peaceful hurricane season for you.

I wouldn't attempt to run heavy power consumers with it. It would mainly be to keep the refrigerator alive, and keep us on line with a laptop. We lost a lot of food after Wilma.

...so it looks like you could use your car as a quiet gasoline generator.

Lawn tractor? Mine is 17 ponies.

If you have to recharge, go ahead and get the generator. The new Honda is very quiet. 17 years in Houston taught me a gen is the only way to go. It's nice to be able to run more than one appliance at a time, if needed, and the wet/dry vac comes in real handy.

Rand

You can buy a Honda generator that has been converted to run Propane. It runs almost as long as a gasoline generator and Propane is much easier to store over long periods of time. Also, it is easier to buy after the Hurricane than gasoline is.

We have a 1 kw generator (your fridge is probably 630 watts with a start up transient on the compressor) on our emergency trailer.

If you really wanted to get fancy check out our trailers at

www.assurecom.com

Jt: I don't think that's really true; headlights alone use at least 110 watts (probably closer to 200 with running lights).

Then there's the rear window defrost - and on current cars very often heated seats and perhaps washer fluid. (And the stereo, and on many more recent cars, the A/C and main heater might well be electrically powered, too!)

The alternator will be rated to power all of those at once without significant battery drain - because all of them (except the rear defrost) may be on for hours at a time, in cold weather at night. (Or in case of the A/C in hot weather... and also the front auxiliary fan will be on!)

A car sitting with all of that stuff off has plenty of spare power (though I don't know that it has enough to run major appliances!), even without getting a high-output alternator.

I would, though, second Bill's point; if you really want a generator, one of those Honda EU superquiets is more appropriate than a car and more efficient, being designed for it - and the non-quiet ones are much cheaper.

(Plus in case of civil emergency, it's probably easier to secure than a running car... not to mention that the effort and cost of getting the alternator upgraded in the car, combined with the lowered fuel economy [slight but non-zero] AND the inability to use the car without depowering your house, well... the generator looks better and better.)

> Jt: I don't think that's really true; headlights alone use at least 110 watts (probably closer to 200 with running lights).

This depends on the vehicle, but let's use it as an example. Most of the midsize GM line from 1998-2005 with a V-6 3.1 or 3.8 liter engine - a pretty common car - (Regal, Grand Prix, etc) use a "standard" alternator rated 94-105 amps at a nominal 13.5v. That 105 amps supplies all the lighting, fans, heater, A/C, and charges the vehicle battery. Using the 200 watt figure and P=IE gives us 14.8 A for full lights (I'm including the dashboard lights there, too). 105 - 14.8 = 90.2 or about 14% of the unit's max-rated load.

>Then there's the rear window defrost - and on current cars very often heated seats and perhaps washer fluid. (And the stereo, and on many more recent cars, the A/C and main heater might well be electrically powered, too!)

Unfortunately, I don't have the amperage figures for these devices, but it is safe to say that the alternator was sized to run them and still provide a small charge to the battery. On our example 2000 Buick Regal, the temperature control system and A/C compressor clutch (the compressor is driven from the engine belt) is powered, but it still uses the engine coolant for the heat source.

>The alternator will be rated to power all of those at once without significant battery drain - because all of them (except the rear defrost) may be on for hours at a time, in cold weather at night. (Or in case of the A/C in hot weather... and also the front auxiliary fan will be on!)

The catch is that the alternator is rated at it's best working speed, i.e. when the engine is running at highway cruise, not idling. At engine idle, it's pretty much matching the car's electrical load with a small charging current going to the battery. This is why it's best to rev the engine slightly when you're attempting to jumpstart another car. I once operated a vehicle that used the engine's alternator in conjunction with an invertor to provide AC power to a rack of electronics. The vehicle was equipped with a "high-idle" solenoid to increase the engine speed to 2500 rpm for a reliable level for the inverter. Naturally, the vehicle alternator was a special very-high-output model that most people wouldn't need, but the concept is the same. Also, motorhomes use a high-output unit to provide charging current to the house batteries as well as to power the vehicle systems AND charge the vehicle battery while on the road. The question I was addressing for Rand was more about reliability than charging capacity. Most alternators fail from heat problems, and the beefier units are less prone to heat-related failures.

>A car sitting with all of that stuff off has plenty of spare power (though I don't know that it has enough to run major appliances!), even without getting a high-output alternator.

Actually, it's fascinating to watch a car's voltmeter (if it has one) if you turn all that stuff on - especially when the vehicle is idling! My company van's voltmeter will drop to below 12v if it's idling at a traffic light, the radio's on and I have the air conditioner blower on 2/3! The electrical system is holding its own at that point with very little charge going into the battery! Also, watch the voltmeter (or just listen to the engine load down) if you ever jumpstart another vehicle.

>I would, though, second Bill's point; if you really want a generator, one of those Honda EU superquiets is more appropriate than a car and more efficient, being designed for it - and the non-quiet ones are much cheaper.

No dispute there. The Hondas have a really good reputation for reliability and low noise. Rand wants to operate the fridge, which has a pretty hefty inductive starting load - that's a job more suited for the genset than a battery bank.

>(Plus in case of civil emergency, it's probably easier to secure than a running car... not to mention that the effort and cost of getting the alternator upgraded in the car, combined with the lowered fuel economy [slight but non-zero] AND the inability to use the car without depowering your house, well... the generator looks better and better.)

Absolutely. A portable genset is great if all you need is to keep the fridge (or furnace, if you're stuck without power in the mountains) going until the mains are back up. But if it comes down to powering something through an invertor powered by the car - it pays to know that the alternator will stay reliable until the emergency is over. For Rand's purposes, the genset is a much better choice than the battery bank - he would be facing a hurricane-related power emergency of unknown duration; if necessary, he could siphon some gas out of the car to power the genset.

Here's some things I learned during the great Seattle windstorm and power outage:

The Honda generators are nice but not maintenance free. There are tasks that need to be performed at 20-, 50-, and 100-hour intervals. If you're running the generator full time, you'll be doing maintenance every day or two. You'll need oil and spare parts, which may be hard to find in a disaster area, so stockpile them in advance.

Do not take fuel for granted, either. Gas pumps don't work when the power's out. The day after the windstorm in Seattle, there were only two gas stations open in my area. Both were limiting purchases to 8 gallons per customer. By that afternoon, both stations had been commandeered by the police department to keep their own vehicles running. (All the police pumps were without power.) There was gas to be had within 20-25 miles, but with fallen trees, power lines, and other debris, driving that far was difficult. Don't assume you'll be able to go out for propane, gas, or anything else.

I've got a cabin that's off the grid, so the problems associated with dealing with an extended power outage are familiar to me. If you're serious about dealing with a really extended outage, you should build a backup system incorporating batteries, a generator, and a renewable energy source. The batteries provide capacity to allow you to power your base load, you recharge them with the renewable energy source as possible (wind or solar), and have a generator set up to handle peak loads. Wind isn't an option where I've got my cabin, but otherwise a wind turbine has a great price point for renewable energy. Best of all, you can tie this stuff in with your grid power supply and use it to cut your electricity bill on an ongoing basis. Xantrex provides a lot of solutions for exactly this application. As far as running your car for power, I think that'll become a easier if hydrogen fuel cells make it into the automotive market in a big way. Fuel cells are just big electrical generators tied into an electric vehicle drivetrain, so tapping off the high voltage DC drivetrain in such a car is going to be a lot easier than straining a little 12 VDC electrical system in current ICE vehicles.

Generators are conspicuous (when they're running) and attractive to thieves, so if you get a generator it might be prudent to figure out a way to secure it.

OTOH, I suspect that many more people in South FL own generators than was the case before the 2005 storms, so your generator might not stand out so much.

OTOH, I suspect that many more people in South FL own generators than was the case before the 2005 storms, so your generator might not stand out so much.

Based on the stories you hear every year of people losing valuable medicine to power outages, I doubt this is the case... I doubt anyone bought a generator once the power came back on.

Out of sight, out of mind. And most people are plain outta their minds.

Actually, hybrid cars can make good generators/UPSes
The DC/DC converter in a Prius is good for about 1Kw at 12 volts, and the high voltage battery is good for about 3KW, more with the engine running, at 220V DC. Here is someone who figured it out.
http://www.priups.com/riddle/answer-1.htm

The engine only runs when the battery starts getting low, charges it up and shuts down. He has had 3 power outages since he set it up.

Yes, a hybrid is also a good choice for backup power. Again, the key is that the drivetrain is designed for high current and higher voltage than a typical car inverter. 3 kW is not bad power output, but not much better than a typical portable generator. A typical North American home uses about 5-10 kW.

For a quiet generator, get one that runs with a Stirling engine.
This looks pretty good.
http://www.whispergen.com/