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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...
There's also the possibility we have some dumb users who start using their Volt as if it was an RV and start running their microwave at tail gates and running power tools all the time without a proper generator. Then start complaining about loss of range. Then there's the service repair calls for a blown fuse cause they wanted to nuke a burrito while blending a smoothie.

I agree, this would be a nice feature but I can understand GM not wanting to deal with the headaches.

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.
Assumes your ICE can output the proper charging power. I think it's the alternator and engine RPM that dictates how much the 12V battery will be charged in an ICE (don't quote me, I'm a car noob who can Google), so you probably won't be running your fridge, but maybe a small TV.
 

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There's also the possibility we have some dumb users who start using their Volt as if it was an RV and start running their microwave at tail gates and running power tools all the time without a proper generator. Then start complaining about loss of range. Then there's the service repair calls for a blown fuse cause they wanted to nuke a burrito while blending a smoothie.
The thing is, though even with all the usage you describe, we are talking at most a 2kW draw. For an OEM solution from the high voltage battery, that is a drop in the bucket compared to normal driving conditions, so the battery really wouldn't be affected by such use. Even as a whole house 10kW backup power source, that is less than 10% of the power pulled from the battery when the Volt is under max acceleration. And less than 50% of the power pulled from the battery when cruising at interstate speeds. It's just insignificant IMHO, and a great feature add.
 

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I'm looking forward to the day when I can use the CCS port for V2G (vehicle to grid). I've done the 12V-to-home thing myself, during an outage, workable, but not ideal. I'm hoping GMs CCS ports aren't so locked down by authentication protection that some hacking can be done to make a bidirectional CCS charge station. Almost makes me want to go buy a used SparkEV with CCS to test out. May be a while until I start hacking a Bolt or other off warranty CCS vehicle.
 

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Discussion Starter #24
Krona: Thanks for the great post.
If the power is out for days, how are you connecting to the internet to post?
Mobile phone service never went down, so I always had Internet/cell phone. And power finally came back yesterday afternoon we were without power for 2.5 days.
 

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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.
Thanks! I'll look into it.
 

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I did a little more research. Using a vehicle with large battery and sometimes power generation is called vehicle to home (V2H) micro-grid. As mentioned there have been products produced for the Japanese market and a V2H is available for cars with fast DC charging as the interconnection is already available. Much to my surprise I found a V2H for the Prius Prime is on the market.

Honda has something on the horizon for the fuel cell car and probably any fast DC charge EV. https://www.cnet.com/roadshow/news/hondas-power-exporter-9000/

The Volt has interesting possibilities due to the nature of PHEV eRev technology. But the lack of DC fast charge CHAdeMO interconnect makes it more difficult. A hack that added CHAdeMO would be the safest bet as the handshake and safety checks are already developed.
 

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This seems like a very nice and quiet solution for temporary off-grid power and if it works, it makes perfect sense when that big battery is already sitting in the garage.

But can the 360V to 14V battery charging circuit in the volt really supply anything close to 2000 watts continuous power? I don't understand why GM would need or want to charge the 12 volt battery this fast. This would be over 166 amps. I can't see why anything in the car would use anywhere near this much 12 volt current unless they use 12 volts for the AC compressor or something.
 

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Discussion Starter #28
This seems like a very nice and quiet solution for temporary off-grid power and if it works, it makes perfect sense when that big battery is already sitting in the garage.

But can the 360V to 14V battery charging circuit in the volt really supply anything close to 2000 watts continuous power? I don't understand why GM would need or want to charge the 12 volt battery this fast. This would be over 166 amps. I can't see why anything in the car would use anywhere near this much 12 volt current unless they use 12 volts for the AC compressor or something.
I agree with you, I did see 3000W on the drive power meter after I purposely let the aux 12V battery down to 11.8V before I turned the car back on, car was in "P" with other electronics including light off, so most of the power went to the 12V Lead Acid Battery. It only showed 3kW for about 10sec before dropping down to 2kW for another 20-30sec then it dropped down to 1kW. I'm not sure what it can handle continuously, but I ran 3-400W continuously (freezer/refrigerator) for +40h with 5min peaks around 1600W (vacuum and refrigerator). I crawled around the car to see if anything got hot. But I could not find any hot spots and no fans kicked on. So I guess I can only speak for a 3-400W draw. Oftentimes the 12V charger was completely off as I could read the 12V Lead Acid Voltage of around 12.7V although the car was on (12V battery fully charged) After some time and about 12.5V the voltage would jump to just under 14.8V while charging, then back to 12.5-12.8V. I'm mentioning this because even at a fairly consistent 3-400W draw the 12V charger would cycle on and off. 2000W continuous seems very high, and something has to get warm or even overheat I would think.
 

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I did a little digging.
This thread: http://gm-volt.com/forum/showthread.php?127593-How-is-the-12-volt-battery-charged and this document: http://nctcog.org/trans/air/programs/evnt/ContractorInspectorOutreachTexasMay2011.pdf both claim that the gen 1 volt APM can supply a maximum of about 165 amps of 14 volt power which is much more than I expected. I suppose there is a good chance the Gen2 volt is similar. It's not clear how much of that power would be required by the car's 12 volt system while operating, nor is it clear how long it can run at maximum load.
 

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I did a little digging.
This thread: http://gm-volt.com/forum/showthread.php?127593-How-is-the-12-volt-battery-charged and this document: http://nctcog.org/trans/air/programs/evnt/ContractorInspectorOutreachTexasMay2011.pdf both claim that the gen 1 volt APM can supply a maximum of about 165 amps of 14 volt power which is much more than I expected. I suppose there is a good chance the Gen2 volt is similar. It's not clear how much of that power would be required by the car's 12 volt system while operating, nor is it clear how long it can run at maximum load.
Yes. This is why approaches like the EV Extend kit have been sized for 1500W continuous power and 3000W surge. It provides some additional head-room for the APM to power the ancillary equipment that runs when the Volt is on and accessories are off (~500W draw), along with a bit of margin in there as well for good measure/safety.
 

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Discussion Starter #31
I did a little digging.
This thread: http://gm-volt.com/forum/showthread.php?127593-How-is-the-12-volt-battery-charged and this document: http://nctcog.org/trans/air/programs/evnt/ContractorInspectorOutreachTexasMay2011.pdf both claim that the gen 1 volt APM can supply a maximum of about 165 amps of 14 volt power which is much more than I expected. I suppose there is a good chance the Gen2 volt is similar. It's not clear how much of that power would be required by the car's 12 volt system while operating, nor is it clear how long it can run at maximum load.
Thanks for digging this up, good to know we have a little over ~2000W on tap (although not continuous due to heat I'd assume), I assume Gen 2 is the same or similar to Gen 1. Surprised to see a 165A charger onboard, although I'm glad we have it for the Emergency Power scenario.
 

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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.
You might have something there! Automotive alternators can deliver quite a bit of current. How would the cost of an inverter compare to the cost of a gas engine with an AC generator? I can see some advantages to using the car alternator, since the car engine has a large gas tank, and doesn't need to be stored, maintained, and serviced separately. If this can be used with other vehicles, and not just the Volt, there might be a significant market.

... edit....

After some quick searching, you can buy this on Amazon today...https://www.amazon.com/ERAYAK-Inverter-Alligator-Refrigerator-Cooler-8099U/dp/B019PXILXA/ref=sr_1_12?ie=UTF8&qid=1476287820&sr=8-12&keywords=power+inverter

They supply up to 1500 Watts. Less than $100.
 

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^^Be aware that the link above is for a "modified sine wave" inverter. Depending on your use, a more expensive "pure sine wave" inverter might be what you need.
 

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Interesting, possible to pair with solar PV?

I have a 2016 Volt and have been wondering about this, and have inquired and expressed interest about the EV Extend. Thanks to the OP for this report, and others for their comments. We live in a rural area with a 5kW solar array and occasionally lose power in the winter for 1 to 3 days, so this seems to be a good option to explore. The inverter for our PV array is a SMA Sunny Boy with a secure power supply, which will output ~12.5A into 120v AC while the sun is shining and the grid is down (or ~16.6A into 120v AC for the newer SMA inverters).

A more esoteric question for those who might be in the know: Does anyone have any idea how simultaneously charging the Volt from the secure power supply, and hooking up an inverter to the 12V battery similar to the OP or the EV Extend option, might work out??? In effect, this would charge the HV battery during the day with enough charge to last overnight and into the next day (dependent on a correspondingly small draw, of course). Lather, Rinse, Repeat.

Note that we already have a small gas generator for camping and emergency use (1600 watt surge/2000 watt peak output), so please don't suggest that we just get a gas generator. I am curious about this set up and if it has been attempted by anyone with a Volt or other EV. I know it's horribly inefficient (DC->AC->DC->AC), but it's a very intriguing hack until V2H or V2G technologies become more available.:D
 

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I have a 2016 Volt and have been wondering about this, and have inquired and expressed interest about the EV Extend. Thanks to the OP for this report, and others for their comments. We live in a rural area with a 5kW solar array and occasionally lose power in the winter for 1 to 3 days, so this seems to be a good option to explore. The inverter for our PV array is a SMA Sunny Boy with a secure power supply, which will output ~12.5A into 120v AC while the sun is shining and the grid is down (or ~16.6A into 120v AC for the newer SMA inverters).

A more esoteric question for those who might be in the know: Does anyone have any idea how simultaneously charging the Volt from the secure power supply, and hooking up an inverter to the 12V battery similar to the OP or the EV Extend option, might work out??? In effect, this would charge the HV battery during the day with enough charge to last overnight and into the next day (dependent on a correspondingly small draw, of course). Lather, Rinse, Repeat.

Note that we already have a small gas generator for camping and emergency use (1600 watt surge/2000 watt peak output), so please don't suggest that we just get a gas generator. I am curious about this set up and if it has been attempted by anyone with a Volt or other EV. I know it's horribly inefficient (DC->AC->DC->AC), but it's a very intriguing hack until V2H or V2G technologies become more available.:D
That should work.
The car is fully operational while plugged in and turned on, you just can't drive.
The accessory path should be fully available regardless of charging or not, so long as the vehicle is turned on.
The only catch is that you need to activate charging while the vehicle is off, then get back in and turn it on.
You can't initiate charge while car is still running from a previous startup.
 

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Interesting, possible to pair with solar PV?
I have a grid-tie 5KW system, many of us look forward to the day when we use Volt to energize the home wiring, then allow the grid tie system to maintain/supplement power. Note my earlier post #23 in this thread. I'll do that myself one day, once I can work out a code compliant system.

In the meantime, I have also experimented with a small off grid solar system that can simultaneously charge the Volt 12V battery, while using a standard inverter to then draw power off the 12V battery and charge the traction battery through a custom EVSE and J1772 inlet. The car is off in this case, and a controller monitors energy going into the 12V battery, and energy going out to the EVSE to prevent deep discharging the 12V battery. The system cycles on and off, depending on the power coming in from the panels. I use a custom EVSE that allows me to set a 6A charge to Volt to minimize power draw on the 12V battery. And I'm also avoiding the final inverter output stage by feeding 120-150V DC into the custom EVSE. So it's an L1 DC EVSE :)

This is still going to take a lot of work to characterize battery performance, repeated high discharge cycles can kill a lead acid battery, but it's been an interesting project. I've also run it with separate 12V buffer battery, ultimately I'd probably go with the separate battery approach. Unfortunately, the day job takes most of my time these days. However, I was able to demo the system at this years NDEW in Austin.

Again, not very practical, very expensive for what it does, but interesting.

Note that the extension of the above idea, is to use a string of panels to generate and buffer 120 VDC. Then just charge Volt directly with that. The trick is the energy buffer. The Supercap math (or cost) doesn't work out, so charge controllers and batteries are still necessary.
 

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Could a person use a small 12V battery with a small 240v inverter to provide the sense voltage the main panel inverters needs in order to turn on and allow the panels to provide power in order to charge the car?

Of course the main disconnect to the grid would need to be off first.
 

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... use a small 12V battery with a small 240v inverter to provide the sense voltage ...
Yes, and exactly what I'll setup eventually. I already have the off-grid 12V backup power distribution in my house. Although you actually need a 120V split phase inverter (US). Code compliance is an issue, but there are manual and automatic load control systems that can achieve this.
 

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I have a 2016 Volt and have been wondering about this, and have inquired and expressed interest about the EV Extend. Thanks to the OP for this report, and others for their comments. We live in a rural area with a 5kW solar array and occasionally lose power in the winter for 1 to 3 days, so this seems to be a good option to explore. The inverter for our PV array is a SMA Sunny Boy with a secure power supply, which will output ~12.5A into 120v AC while the sun is shining and the grid is down (or ~16.6A into 120v AC for the newer SMA inverters).

A more esoteric question for those who might be in the know: Does anyone have any idea how simultaneously charging the Volt from the secure power supply, and hooking up an inverter to the 12V battery similar to the OP or the EV Extend option, might work out??? In effect, this would charge the HV battery during the day with enough charge to last overnight and into the next day (dependent on a correspondingly small draw, of course). Lather, Rinse, Repeat.

Note that we already have a small gas generator for camping and emergency use (1600 watt surge/2000 watt peak output), so please don't suggest that we just get a gas generator. I am curious about this set up and if it has been attempted by anyone with a Volt or other EV. I know it's horribly inefficient (DC->AC->DC->AC), but it's a very intriguing hack until V2H or V2G technologies become more available.:D
Since the SMA secure 120vac power can be sporadic as a function of solar insolation (clouds etc..), I would set up an external 12v battery bank to be charged by the SMA (AC->DC). Then from this battery bank you can inverter (DC->AC) 12vdc-->120vac and use your Volt L1 EVSE to charge the Volt main pack. Of course this set up is not maximizing your 5kw PV array, but it's relatively easy and cost effective. It depends how frequent your outages are.
 
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