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Discussion Starter #1 (Edited)
I took a direct hit by the recent hurricane Matthew, and we are a little over 2 days into not having any power.
I have a 2017 Volt and have been running essential household power applications off my Volt. I've been using the onboard 12V DC Lead Acid battery to power a 3000W 12V DC inverter producing 120V AC. As long as you have the Volt turned on the main lithium 18.4 kWh (about 14kWh usable) battery will charge the 12V auxiliary battery. I'm not entirely sure of the power rating of this onboard 12V charger, but my guess is somewhere around 2000W (perhaps someone can confirm).

I have a Volt Meter hooked up to the auxiliary 12V battery, and you can tell when the main battery is charging the 12V battery, the Voltage reads above 14V. It's important to not miss this step as the small auxiliary 12V battery would otherwise deplete very rapidly.

The newer Gen 1 Volts the Gen 2 Volts will shut down after some time, Gen 2 seems to be about 1.5h or so. I noticed that some folks have had good luck keeping the later model Gen 1 running by simply holding the sifter button in with a rubber band. I tried this on my Gen 2 and it works there as well.

I've been successfully running a full size freezer/refrigerator for almost 2 days. I'm also charging various electronics and I even ran the vacuum cleaner a few times (on lower power mine has 800-1600W range).

It's also important to note that the limiting power output of this setup is not the 3000W 12V DC - 120V AC inverter I purchased, rather it's the onboard 12V chargers capability, using the 360V main battery to charge the 12V aux battery.

On average I'm drawing just under 400W continuous running the refrigerator. The refrigerator does however need about 1,500W to start.

All it took was a 2-3000W inverter and a rubber band.

There are several ways to charge the main battery. 1) You can wait for it to be depleted and the engine/generator will start. 2) You can also hit Mountain Mode and the engine/generator will start at about 25% remaining. 3) Pop the hood at any time with the car running the engine/generator will start and any charge level. The engine seems to be charging the battery with about 3000W max at any of the above 3 scenarios.

Of course it would be better to run an inverter directly off the 360V main 18.4kWh lithium DC battery. But 360V inverters are harder to come by and it would require more engineering on my end. The advantage would be the availability of higher Watt and lower losses running the power through only one Inverter vs. 2 (360V DC -> 12V DC -> 120V AC).

I'm surprised that this feature is not built in the Volt with proper protection and power limitation. I have the best Battery Backup/Generator combo money can buy in my garage and I'm not able to use that setup in emergency situation. I did this for $250 (cost of Inverter) I'm sure GM could have it built in, monitored and protected installed for a $300 option. I think if would be a great selling point.

After 2 days I’ve used about 9kWh out of the available 14kWh. And I ran the engine/generator for about 10min making sure it would charge and trying out different ways to get the engine/generator to start. It seems to be charging at 3,000W when running gauging from the onboard power meter. The car records all usage as driving so I’m sure the eMPG will be terrible for these 2 days.

While on I 1) turn all driving lights off 2) dim the interior lights and 3) turn off the center information display in the settings menu. The car itself, while on, does not seem to use that much power my guess is 50W.
 

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Why can't you use the best Battery Backup/Generator combo (Volt) money can buy? It seems like you are using it.
 

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As for the trick to keep the vehicle powered on more than 1.5 hours, wouldn't shifting it into neutral and making certain the EPB is engaged basically do the same thing?
 

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That is great it is working out so well for you. Thanks for the technical details. I have been tempted to get the same set-up. However, I am kind of torn between this and getting a stand-alone gas powered generator. The cheaper ones can be price competitive with your solution, and would have the advantage of being able to power home appliances while you use your car for transportation. For instance, you could still drive to work for the day while leaving the generator running at home keeping the refrigerator cold and preventing the loss of your food. But a generator has drawbacks as well, such as noise, and it means owning yet one more thing to maintain and store. I’m not really sure which makes more sense.

I have been very lucky with power outages, never having lost it for more than a few hours despite several storms that have had a bigger impact on many other people in my county, in some cases more than a week.
 

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A kit is made to do this on the Gen 1 Volt. It was temporarily discontinued when the Gen 2 was introduced, but back by popular demand: http://www.evextend.com/Emergency-Power-Kit.php

It is in lieu of direct high voltage battery access from the OEM, which while preferred, would be a dangerous undertaking for a do-it-yourselfer, and also cause concerns with the high voltage battery warranty.

EVExtend is looking into making a similar kit for the Gen 2 Volt. It is doable, but there are some hurdles to overcome with proper connection points. These kits do exactly what you are accomplishing, except they add an inline fuse for safety and use high power DC connectors for quick connection/use. This enables convenient/quick operation beyond long-term outages to include items like recreational uses (UAV, RC vehicles) and also other off-grid uses like camping accessories.

You do still need to do the rubber band trick though for extended operation. ;)
 

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Great post Krona, you made a number of good points. A backup power option with one or two 20 amp 120 VAC circuits would be an attractive option for many people
 

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Great post Krona, you made a number of good points. A backup power option with one or two 20 amp 120 VAC circuits would be an attractive option for many people
I'm amazed the OEM doesn't offer this. It's not a lot of added cost for them. Heck, they could even offer a 10kW output option, that is much less power than driving on the highway at a constant speed. And the electronics are mostly already there given the motor controller, which already converts DC to AC for propulsion (albeit three phase).

I think their real limiting factor is that they don't know how to address battery warranty language and details there, since everything right now is based on mileage. It's not insurmountable, but when exploring it they probably come back to the fact that they're a car company, not a backup generator provider. Short-sighted, in my humble opinion...
 

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rubber band trick
I invented the rubber band trick!

People were using C-clamps and other clamps for woodworking and scratching the heck out of their shifter. Rubber band is way easier and doesn't scratch.

Eventually, V2H (Vehicle to Home/House) technology will work everywhere. The Japanese are working on it.
 

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Discussion Starter #12
Steverino - I mean in a less complicated way with a better and perhaps GM sponsored option. I really think it would be a great selling point marketing these vehicles as backup battery and backup generators. All equipment less than a 3000W or so inverter is available in the car. If there was a dedicated "Generator Mode" and a HV Inverter installed, even if it was a $500 option it would be a great selling point compared to pure Electric cars. I'm on my 2nd Volt and when getting the Gen 2 I was looking very closely at the Tesla, but decided on the Volt because of where I live, there are not many chargers available and especially not on the route where work takes me, so I wanted a range extender. Using the engine as a generator would be an added plus. Anyway, just wish it was built in with appropriate protection. I still don't know the Continuous/Max rating of the onboard 12V charger.

ChevyEMF - I got a 3000W continuous / 6000W peak Inverter from Harbor Freight, it was all that was available after the hurricane, I got the last one and had no other options. But it ended up working great. I'm sure anything over 2000W would work, pure sine wave inverters are preferred. I actually got a modified sine wave inverter because it was all I could find locally, but it worked. Having more time I might have gotten something else, but it worked great. I can't post links, but if you Google "Harbor Freight 3000W Inverter", it's the first hit by CEN-TECH. This is by no means a high end Inverter, but it does the job well.

freshcut - Putting the car in Neutral seems to activate the drive unit, I realize it's not providing torque towards the drivetrain but the electronics definitely makes more noise when in N vs. P, leading me to believe that the cars power usage is higher in this mode vs. P with the shifter button pressed. N seems to engage the electric motor controller. In P with shifter button pressed and the above mentioned configuration I think the car us using 50W or less.

Barry - I personally like the Volt option, the Inverter was only $280 and you can probably find it cheaper if you have more time than I had. I also have a 2nd car so that might change the preference. Using the Volt I know I always have a functioning power source and I do not need to store a generator. It's also a lot quieter and only needs to run every 2 days or so. So conceivably you could weather a 2 day power outage without ever running the motor.

ClarksonCote - Agreed
 

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garyka - The battery was able to supply what I needed for 2 days. I only used 0.1 gallon of fuel while trying to figure out how I could start the engine and charge the main battery 1) wait until depleted 2) mountain mode and the engine would start at 25% left, and 3) popping the hood, with this you can start anytime. The car motor seems to charge the main battery with 2000-3000W, I'm not sure how much the onboard 360V to 12V charger will charge with but I assume about 2000-2500W. The Inverter I purchased ran about 300-2000W, that means about 160A peak and 24A continuous, figuring a 12.5V from the battery. The Aux battery voltage would read anywhere from 12.5-14.8 depending on where the car was in the charge cycle and the charge level of the 12V Lead Acid battery.
 

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You are looking for something like an inverter for solar panels. I found this inverter that might work. It's not cheap and it might be less expensive to use a good quality generator, maybe a Honda.

It outputs 220V AC, not sure if it has a center tap for two 110V lines but that could be done with another transformer if necessary.

It would be important to have safe interconnects between the car and the inverter. A one time modification to install safe plugs on the car and after that no worries. I have no suggestion for the hardware for that and it would be important to be very familiar with the high voltage hardware on the car before attempting any modifications.

Link to the inverter, this is an example and the first one I found. I'm sure there are many others and there might even be one for EV high voltage systems. I found evidence that it has been isolated as a market opportunity.
 

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I invented the rubber band trick!

People were using C-clamps and other clamps for woodworking and scratching the heck out of their shifter. Rubber band is way easier and doesn't scratch.

Eventually, V2H (Vehicle to Home/House) technology will work everywhere. The Japanese are working on it.
At the recent Drive Electric event here, Nissan had a tent that was powered by a portable CHAdeMO V2G unit from a Leaf. The V2G unit was made by Nichicon. (Nichicon is a major electronic components mfr in Japan.)

Last week we had a power outage here. About 1.5 hours into it, it was getting dark. So I decided to get my inverter out of the garage to at least power some lights off the Volt. Just as I walked out the door, the power came back on. Definitely piqued my interest though - as my inverter is too small to power the fridge.
 

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garyka - The battery was able to supply what I needed for 2 days. I only used 0.1 gallon of fuel while trying to figure out how I could start the engine and charge the main battery 1) wait until depleted 2) mountain mode and the engine would start at 25% left, and 3) popping the hood, with this you can start anytime. The car motor seems to charge the main battery with 2000-3000W, I'm not sure how much the onboard 360V to 12V charger will charge with but I assume about 2000-2500W. The Inverter I purchased ran about 300-2000W, that means about 160A peak and 24A continuous, figuring a 12.5V from the battery. The Aux battery voltage would read anywhere from 12.5-14.8 depending on where the car was in the charge cycle and the charge level of the 12V Lead Acid battery.
Krona, one other thing I'll note. If you just leave the Volt on, once the HV battery is depleted, the car will run the engine for a small amount of time (i.e. 5 minutes) and then turn back off for about 30 minutes or so, depending on your load. It can repeat this indefinitely as long as there's gasoline in the tank. It basically charges up a small buffer of about 1kWh or so each time.

This isn't as efficient as using Mountain Mode (in this back-up power use case, I'm not talking Volting here (an inside joke if you're new to our forum ;) ) but the benefit is you don't have to worry about recharging with Mountain Mode. Of course, always make sure there is proper ventilation, though the concern is minimized a bit since the engine is not running very often.

Many people have used the Volt for extended periods in this manner with the Gen 1 Volt EVExtend kit mentioned above.

Oh, one other note: If anyone is interested in the eventual EVExtend kit for the Gen 2 Volt, contact EVExtend and express your interest. You'll be notified when the kit becomes available: http://www.evextend.com/Contact-Us.php
 

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Krona: Thanks for the great post.
If the power is out for days, how are you connecting to the internet to post?
 

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It's not really a new idea. It would even work with an ICE car. The Volt obviously is quieter and the engine need not run continuously. A gas or propane backup generator can do the same job without tying up the car.
 
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