Prius Powers Home During Ice Storm

[bananas]

http://gas2.org/2009/01/02/prius-powers-home-during-ice-storm/

Prius Powers Home During Ice Storm
Written by Susan Kraemer
Published on January 2nd, 2009 in Advanced Batteries, Energy Storage, Hybrid-electric EVs

Ice Storm Victim Improvises Prius-to-Home Energy Generator

A Massachusetts man - faced with no power in the recent ice storm, powered up the family Prius to create electricity: The hybrid car made enough electricity to run the essentials; the fridge, the lights, the TV, the wood-stove fan. During the power outage, it supplied 17 Kilowatt hours of energy to his home for three days.

How did he do it? The Harvard Press described how the hybrid’s battery ran the house essentials for electrical engineer John Sweeney and family. He dug up an inverter which made 120v AC from 12v DC current and he wired it into the hybrid electric Prius, creating V2G technology on the fly.

<snip>

Last year the NYT reported on a similar case of another disaster victim powering his home in the same way; but this one employed his P2H power during a hurricane.

[orleans]

1. now that is totally impressive!

however--even if i had a prius i still wouldn't know how to do that with it.

[katusha]

2. it's simple if you have an inverter

<http://en.wikipedia.org/wiki/Inverter_(electrical)>

plug the inverter into the lighter, plug power strip into inverter then run extension cords to fridge etc.

[orleans]

8. they're only around forty bucks? not bad for emergencies.

http://www.radioshack.com/product/index.jsp?productId=2421176

oh, now i read lapfog_1's post--i guess the cheap one is not the way to go necessarily.

[lapfog_1]

10. Hey, if all you need is a laptop and router or modem...

$40 is well spent. I keep a cheap one with the lighter plug in my car all the time. Then if I happen to be stuck somewhere (or I just went to the store and they didn't have what I wanted), I plug in my laptop and either find a WiFi hotspot or (now) use my 3G modem and surf to find where I should go next.

Of course, a good phone these days will do all that. I just don't happen to have one of those yet. :)

[lapfog_1]

3. It's actually pretty easy.

And you don't need a hybrid to do it. Any vehicle will do (but the amount of power from a car alternator will restrict how much stuff you can plug in).

Connect jumper cables (the more power, the better the cables should be) to the car.

Connect the other end of the jumpers to an inverter. Buy a good one, not the $50 cigarette lighter plug in version.

Plug your TV, your laptop computer, your "fridge" (if it is recent energy star compliant version) directly into the AC outlets on your inverter. Calculate how many watts your electronics and appliances peak at and stay WELL under what the inverter can deliver.

Wiring the inverter into the house wiring is a much more difficult task, and you should consult your power company for the approved cutoffs, etc. Not to mention that even a Prius probably can't power everything in your home (electric baseboard heat, electric hot water heaters, ovens, stove tops, fridge, multiple TVs, hair driers, etc, etc).

Better to just buy the extension cords and plug the appliance (low power ones) into the inverter for such emergency situations.

Edit to add!

VERY IMPORTANT! You need to keep your vehicle engine running to use this "emergency generator" aspect. Otherwise you will draw down the battery very very quickly. So... make sure your car is either in the driveway or that the garage door is open and the car parked so the exhaust is aimed outside! Otherwise you run the risk of dying from carbon monoxide poisoning.

And, not directly related, DO NOT COOK with charcoal indoors! (I had a friend that died this way about 12 years ago!)

[katusha]

4. so the cheapy inverters no good?

never tried anything substantial off of one so....

[lapfog_1]

5. Oh they work for like keeping a laptop up an running.

But I wouldn't put a fridge on one. They tend to overheat when run at near their highest rated wattage.

I have a 2K inverter... it's fairly large with nice extruded aluminum casing with lots of heat sink fins.

Like this one (I couldn't quickly find mine online)...

[katusha]

6. good info, thx n/t

[Lasher]

11. How much does a 2kw inverter cost?

Here's what portable generators cost and what you can do with them:

SMALL PORTABLE
3,000 to 4,000 watts
What it powers: The basics, including items such as: • Refrigerator (600 w) • Several lights (400 w) • Sump pump (600 w) • TV (350 w) • Microwave (1,500 w)
Price range: $400 to $800 for most; more for inverter models.

MIDSIZED PORTABLE
4,500 to 7,000 watts
What it powers: Same as small, plus: • Portable heater (1,300 w) or window air conditioner (1,000 w) • Computer (250 w) • More lights (400 w) Or, with a transfer switch, about $600: • Furnace fan (500 w) • Water pump (400 w)
Price range: $500 to $1,000 for most.

LARGE PORTABLE
10,000 watts
What it powers: Same as midized, plus: • Water heater (3,000 w) • Or central air conditioning (5,000 w) or range (4,500 w)
Price range: $2,000 to $3,000.

Here are typical wattage requirements:

Central air conditioner 5,000
Coffeemaker 1,000
Computer 250
Clothes dryer (electric) 4,800
Freezer 500
Furnace fan 500
Garage-door opener 600
Hair dryer 1,200
Lights (5) 400
Microwave 1,500
Portable heater 1,300
Radio 100
Range (electric, 3 elements) 4,500
Refrigerator 600
Sump pump 600
Television 350
Washing machine 400
Water heater 3,000
Well pump 400
Window air conditioner 1,000

Information from Consumer Reports

[lapfog_1]

12. 2kw inverters go from $150 to $600 for the deluxe

heavy duty Tripplite model.

The one I have was about $180 and it works fairly well. Always good to post the list of typical appliances and their draw. Also, a lot of devices that have electric motors draw significantly more power when first starting than when in continuous operation. Always be aware of that and try to sequence the start of something like a desk side computer with more than one or two disk drives... try to power off the TV and the fridge if you think it's going to be too much for either the power source or the inverter... after the computer or whatever is running, you can power the TV and the fridge back on. Remember that the compressor unit on the fridge also has a startup draw as well, you can usually find how much energy it takes when starting up by reading the detailed spec sheet that came with the appliance.

[Lasher]

13. So what do you use to push this 2KW inverter?

Plain ol' 12 volt car battery? Connected to vehicle with engine running 100% of the time or not?

[lapfog_1]

15. It;s actually in use with a generator.

But you could hook it up to car battery terminals with the car running.

Many over the road truck drivers have such inverters permanently wired into their electrical system with deep cycle marine batteries providing for their sleepers electrical needs when the engine isn't running. There are even "APUs" that you can buy that are much like reefer units for trailers. That is, a genset totally unconnected to the engine wiring that starts automatically when the batteries are getting low and provides watts to a major inverter for running everything in the sleeper. I believe that many of the larger RVs have similar setups.

[One_Life_To_Give]

17. Alternator can't keep up 2KW

The typical car can generate maybe 50-60 Amps at 2000 RPM. So 600 watts sustained is the max you can do without killing the battery and burning up the alternator.

[lapfog_1]

19. Yes, that's true...

which is why you have to match the power usage with both the power source and the inverter.

Using a 2KW inverter with a car alternator is fine, just don't present a load of more than what the alternator is capable of producing.

And I would use 1000 RPM or less for the calculations since it's quite likely that the car will be idling without someone either sitting in it and pressing on the accelerator or wedging some sort of artificial "foot" to race the engine a bit (not recommended).

However, you can safely power a laptop, a cell phone and perhaps a flat panel TV (small LCD) and maybe some other small electronic device.

[Dead_Parrot]

7. There seems something fundamentally lopsided...

...in worrying about powering your fridge during an ice-storm.

But, maybe that's just me: I would classify TV as "essential", either.

Nice MacGyvering, either way. :)

[lapfog_1]

9. In severe weather situation, the TV has replaced the radio

as the primary source of up to the minute reports.

Actually, I should say that the TV and the internet have replaced the radio.

In addition, when you are snowed in (when I was growing up, we would occasionally get snowed in for up to 2 weeks sometimes), the TV is something that one uses to occupy ones time, especially kids. Howling blizzards are not something to go out and play in... and board games get to be tiresome after a day or two... And even reading gets to be boring. We would tune in to see the progress on plowing the roads so we would know when to bother trying to clear our drive (about a 1/4 mile long) to meet the snow plows.

As for the fridge thing... yeah, that's tricky. But many items that need to be chilled do not do well when frozen (produce especially). We would often throw everything from the freezer into the snow drift behind the house and cover it with couple of feet of snow when we lost power. The contents of the fridge were cooked first, over a wood fire in the fireplace. After that was gone, then we moved into eating the frozen stuff and the canned goods.

[Dead_Parrot]

14. When I was a lad, books and a piano were enough...

...mind you, I remember being surprised to find out TV came in colour. Sigh.

I guess it shouldn't shock me that TV is used for information more than radio these days: Times change. Having said that, I have a nice multiband radio that will pluck the audio channel from the TV signal, so until everything goes digital I'm OK. Plus, it runs off 6AA batteries which is more than can be said for my TV. And snooping on the police is more entertaining. :evilgrin:

The "fridge, not frozen" used to get sorted by finding a nice cold room/porch/shed/whatever and putting everything there, although a bowl of ice in the non-functional fridge worked quite well.

[here_is_to_hope]

16. Heck, I have been doing this for years!

As an ex truck driver, I have long used the inverters for such emergencies.
Most have low voltage warning buzzers or will kick off at 11.6 volts (my larger one does).
Running a fridge though...while some inverters are rated at 3k peak, its not likely they will give you that.
The other issue is the wave pattern, some computers and other electronics do not like the square sine wave pattern of electricity these inverters put out.
The better inverters are the same as what you see in home and boat solar/wind power systems.
I think a better stand-by emergency power source than a generator is having 6 deep cycle 12 volt batteries that are trickled charge from a charger and and inverter.
You can inter-tie to the house but a short extension cord and a simple surge protector strip works fine for the essentials.
Our last power outage had the neighbors over for a marathon Nintendo session...
Avoid any appliance with a heating element, heavy current draw!

[One_Life_To_Give]

18. Prius 12V??

I thought the 12V system on the Prius was just Tertiary, with the main power being at a much higher voltage. Granted 17kWhr over 72hrs isn't much power. Anyone know for certain?

[skids]

20. Yep this could have been done with any car...

If he was feeding off the 12V rather than the HV cells, then
he could have used the same inverter on any car battery. The
Prius might have been a bit more of an efficient generator,
though, considering idling cars are extremely inefficient
whereas the Prius never "idles" it runs the engine at cruising
speed while it is parked, charges up the HV cells, and then
turns off the engine. So it probably used a whole lot less gas.

The 12V battery, which is smaller than most, is charged
by a downcoverter from the HV cells. I think there are invertor
kits for the HV cells but I'm not positive they aren't just cheapo
12V kits that just don't tell you they use the 12V. It's probably
not a huge efficiency penalty -- somewhere in the 20% range --
5-10% for the downcovert, 10-15 for the invertor stage since the
higher the input DC votage on those the more efficient they can
be.