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Discussion Starter #1
Is it possible to charge one's Bolt from a portable generator? If so, what rated generator would one need for such? All this talk of hurricanes and long-term power outages got me to thinking about getting a generator "just in case" so I could keep the refrigerator and freezer cold, plus have a light or two so I don't break a toe in the dark. Then I got to wondering if it would be possible to use one to charge my Bolt. Thoughts? :confused:
 

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yes - it's possible but depending on the car's charging electronics not all generators are created equal and their power may not be "pure" enough to keep the car's charging system happy - grounding is also a trick and you need to make sure the generator has good grounding - this has been discussed at length in the Tesla forums and the conclusion seems to be:"

"yes" - but get a high quality generator (good/pure power production) and make sure to ground it properly so you don't trip up the car's charging sensors.

32 AMP is 7,680 watts - so you'll need at least a 9,000 watt generator if you want to charge the car from zero in less than 10 hours. Obviously you can charge it slower but they you'll need an EVSE that can be plugged into the generator at the proper load.

these links might help you:

https://forums.tesla.com/forum/forums/charging-generator-0

The two main problems are:
(1) Most generators don’t have a real ground, and the Tesla charging system will sense this and won’t run.
(2) Most generators don’t generate a clean AC sine wave output, and the Tesla charging system doesn’t like that either. Some good generators do have this, though.

https://forums.tesla.com/forum/forums/it-safe-charge-ms-portable-generat...
https://forums.tesla.com/forum/forums/model-s-honda-240v-generator-unlim...
https://forums.tesla.com/forum/forums/charging-battery-using-home-standb...
https://forums.tesla.com/forum/forums/seeking-info-charging-ms-gas-gener...
https://teslamotorsclub.com/tmc/threads/charging-a-model-s-with-a-small-...
https://teslamotorsclub.com/tmc/threads/charging-model-s-with-a-diesel-g...
https://teslamotorsclub.com/tmc/threads/hack-charging-off-generator.2490...
https://teslamotorsclub.com/tmc/threads/stupid-question-emergency-chargi...


I apologize for all this information being Tesla centric - but I'm a fan (we all know this) and they have the lead in experience in this area - not all of this experience will necessarily translate to the Chevy Bolt - but it's the best place we have to start…my feeling is the Chevy couldn't be more finicky than the Tesla, in fact it might be more tolerant than the Tesla for different charging solutions - but that's just pure guess work on my part.

This is one scenario where the fact that you can override the charging AMP's in Tesla's charging software on the dash is a major advantage. When charging off a generator it's nice to be able to dial the AMP's down to adjust the car's load on the generator - since Chevy doesn't offer this ability you have to go with an EVSE that can adjust AMP's based on plug-type, software, or configuration switches on the charger.
 

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I have a champion generator I got from Costco for the occasional power outage - it's 8,000 watts - and I have charged my Tesla @ 240volts/24 amps using the generator as a test. when using this generator I "back feed" the generator into the house grid (isolated from the grid) - so I get ground form the House's normal ground - The Tesla UMC had no problem charging from the champion generator tied into my home's power grid via a plug…

something like this:

https://www.championpowerequipment.com/product/100230-7200-watt-dual-fuel-generator/
 

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Discussion Starter #4
I have a champion generator I got from Costco for the occasional power outage . . .
Thank you, David, for all this info. Much appreciated! :)

I have looked at the Champion generators and they seem to be solid. I confess I'm leaning toward Champion or Generac. I'd love to have a Generac whole-house, natural gas, standby generator (on my wish list!) but thinking about a portable in the interim.
 

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I have a whole house back up generator that runs everything in the house except for heat and a/c and the cars charge fine on the generator. GM advises against charging with a small household generator. At least that was case with the gen 1 Volt.
 

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the key math to remember is: AMP x Volts = watts

charging at 32 amps * 240 volts = 7,680 watts - which is the max charge rate of the Bolt - an 8,000 watt generator should work in theory for that but it would be tight 9,000/10,000 watts would be better if you want to charge at 32 amps…

24 amps * 240 volts = 5,760 watts - which is still a decent charge rate and well with in the capacity of 7,000/8,000 watt gas generator…this would be a 30 amp NEMA plug for a 24 amp charge rate - so you'd need a EVSE charger that could plug into a NEMA 10-30 or 14-30 plug on the generator…

example the champion generator I have has two 30 AMP plugs (NEMA L14-30R and NEMA L5-30R) - both of these are circular "locking" plugs - and would be difficult to find a plug for an EVSE that would plug directly into these - but there are ample "pig-tails" that will convert these locking plugs into NEMA 10-30 or 14-30 plugs…once you have the conversion pig-tail you then need a charger (mobile or otherwise) that simply plugs into the NEMA plug you now have on the pig-tail…

The Tesla Universal Mobile Charger (UMC) has NEMA 10-30/14-30 adapter plugs - so plugging a Tesla UMC into the generator via one of these pig-tails would report to the Bolt 24 amps of available charging power, and the Bolt would proceed to charge at 24 amps (assuming you have the JDapter) - there are other mobile EVSE's that most likely have NEMA 10-30/14-30 plugs so they would work as well.

so basic plan would be:

1. how fast do you want to be able to charge the Bolt - I would suggest 16, 20, 24, or 32 amps @ 240 volts should be your target
2. do the math as to how much wattage that is
3. find/size a generator for the watts required + some overhead (I would oversize the generator by 20% for my target charging wattage)
4. review what plugs on are the generator
5. find an EVSE that can operate at your target wattage/volts/amps either natively or via adapters or via configuration
6. make sure you have the necessary pig-tails/adapters to plug the EVSE into the generator - and probably a 240 volt extension cord (expensive) because you aren't supposed to run the generator in an enclosed area (like a garage) - so you'll need to have someplace to "put" the generator where it can run happily and - you'll need to be able to run wire/extension cord to somewhere close to where you plan to charge the car.
7. make sure you have a grounding solution for the generator - there is ground hookup screw on the champion - simply running a ground wire from the ground hookup to the house ground should be fine - but I'm not a licensed electrician
8. determine what fuel you're most likely to use for said generator - they have different watt ratings for LPG vs. GAS vs. NG

then get all the stuff you need - in my experience the portable version will run about $1000'ish for high quality generator that will be able to charge at 240 volts - tanks, pig-tails, and other equipments so that you could actually use the generator during an outage all add up…

when I did it the portable version ended up being a significant %'age of the cost of a whole-house generator which is a way better solution IMHO - if I had it to do over again I would just invest in a 10,000/15,000 watt whole house generator and just go with that - I found a dual fuel propane/natural gas - and could tie it to my house's NG supply, but if that's out run it with LPG tanks…

short answer is yes you can charge from a generator - longer answer is if you want it to actually work, work well, and work when you need it to - there is some planning required and some equipment (adapters and such) that you need to have on hand which ads to the cost.
 

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since the last post was from about 1.5 years ago I was wondering the following;
#1 . has anyone had any luck finding a gas generator that will supply pure sine power at 240v? Whats been Your experience with it?
#2 . There sems to be more "solar generators" on the market which is basically a very large portable battery pack with dc-ac inverter and possibly a charge controller. Some of these like Kodiak Inergy seem to be well rated but also very expensive. Anyone use these successfully for charging a Bolt yet? What was the brand and cost? How many miles did it add? How long did it take?
 

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since the last post was from about 1.5 years ago I was wondering the following;
#1 . has anyone had any luck finding a gas generator that will supply pure sine power at 240v? Whats been Your experience with it?
#2 . There sems to be more "solar generators" on the market which is basically a very large portable battery pack with dc-ac inverter and possibly a charge controller. Some of these like Kodiak Inergy seem to be well rated but also very expensive. Anyone use these successfully for charging a Bolt yet? What was the brand and cost? How many miles did it add? How long did it take?

I have a 5kW array on my house that produces from 20kWh to 35kWh per day, depending on season. I coupled that with two Powerwalls that hold 27kWh in total. I can go completely of-grid, in an emergency, and last indefinitely without sustained rain.

At best, this setup would take two full days (probably three) to fully charge my Bolt, with nothing left over to run my house.

All told...~$30k out of pocket.

Charging a Bolt from a portable PV/Battery/Inverter system isn't very practical, even if you were only using the OEM EVSE at 8A and 120V, which is ~1kW.
 

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Hello Greg, Yes I realize charging from that kind of system is not ideal. I was thinking it might be a good backup plan vs. running out of juice on a road trip and having to call onstar for roadside help. I am thinking that propbably the most You could get from the solar "generator" might be another 5 miles but if You planned wrong and were off by a few miles it might be enough to help. I was also thinking about using it during the winter with a small heater to make a better efficiency vs. the car's HVAC. Wonderful Home setup BTW!
 

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When you are on a trip, this generator is of no use if left at home. Carrying a 236 pound, $869 gas generator with 5.7 gallons of gas, providing less than 6 kW, adding ~ 20 range miles per charging hour (rmpch), (which generator you cannot run unless the EV is stopped) for a road trip in an EV seems to be missing the point. Even here in WV, Level 2 stations are found ~ every 20-80 miles. While we have NO DCFC stations with CCS plugs in the whole State, one can usually make it to Columbus, OH, Hagerstown, MD, Lexington, VA, or to one of many places along I-81 with minimal hyper-miling. Some "before trip" planning is needed for a trip of over 238 miles, but this is not hard. In my mind, a gasoline generator is not the solution. In fact, IF you can get to a CCS plug close to your home, you could use your Bolt EV as a source of stored energy, and power 2200 watts worth of 110V appliances with a $200 power inverter, two extension cords and two power strips, for about 1.5 days.
 

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When you are on a trip, this generator is of no use if left at home. Carrying a 236 pound, $869 gas generator with 5.7 gallons of gas, providing less than 6 kW, adding ~ 20 range miles per charging hour (rmpch), (which generator you cannot run unless the EV is stopped) for a road trip in an EV seems to be missing the point. Even here in WV, Level 2 stations are found ~ every 20-80 miles. While we have NO DCFC stations with CCS plugs in the whole State, one can usually make it to Columbus, OH, Hagerstown, MD, Lexington, VA, or to one of many places along I-81 with minimal hyper-miling. Some "before trip" planning is needed for a trip of over 238 miles, but this is not hard. In my mind, a gasoline generator is not the solution. In fact, IF you can get to a CCS plug close to your home, you could use your Bolt EV as a source of stored energy, and power 2200 watts worth of 110V appliances with a $200 power inverter, two extension cords and two power strips, for about 1.5 days.

The Bolt's DC-DC is max rated to 1600W *at the aux battery*. I've got a 150A fused 120A Anderson connector on the battery, with 10' of #2AWG welding cable extension cord to a 1500W pure sine wave inverter. If I pull any more than about 1000W *from the AC side*, the Bolt's systems can't keep up, and the aux battery voltage will drop to it's ultimate demise.


2200W at 110V AC ain't gonna happen...:eek:
 

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So, you're going to spend $10k for generator, cords, etc. in order to charge the car a couple times, maybe? What's the $/mile on that?

One trick for smoothing a bad generator or inverter output: Add resistive load like incandescent bulbs (cheap), heating elements (toaster, hair dryer, space heater, etc.) They smooth the output and may make it good enough.

Unless you have some location other than your house to use the generator, I would strongly suggest a mounted house sized generator over a portable.
Portables quickly go from 1k to 5k without much increase in power delivered and still being undersized for delivering one heavy load. 5k is about the start of permanent ones that are far more capable. Note that many permanent ones are NOT capable of the whole house AND require being close to your electric panel AND require potentially extensive modifications to your electrical panel.

I will also point out the vast majority of you live somewhere where you won't die from lack of power, so a generator is really more of convenience rather than life saving/sustaining. I would suggest planning to charge the car slowly so that the rest of the power can go to other activities.
My cheap generator alternative: a decent inverter plugged into your (assumedly gas) car. This would allow some lights, charging etc. all for about $100. When the fuel runs low, you just drive to the gas station and fill up.
I have thought about getting a PowerWall as my generator, but they're not rated for being outside (in MN winters), and they're expensive.
 

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So, you're going to spend $10k for generator, cords, etc. in order to charge the car a couple times, maybe? What's the $/mile on that?

One trick for smoothing a bad generator or inverter output: Add resistive load like incandescent bulbs (cheap), heating elements (toaster, hair dryer, space heater, etc.) They smooth the output and may make it good enough.

Unless you have some location other than your house to use the generator, I would strongly suggest a mounted house sized generator over a portable.
Portables quickly go from 1k to 5k without much increase in power delivered and still being undersized for delivering one heavy load. 5k is about the start of permanent ones that are far more capable. Note that many permanent ones are NOT capable of the whole house AND require being close to your electric panel AND require potentially extensive modifications to your electrical panel.

I will also point out the vast majority of you live somewhere where you won't die from lack of power, so a generator is really more of convenience rather than life saving/sustaining. I would suggest planning to charge the car slowly so that the rest of the power can go to other activities.
My cheap generator alternative: a decent inverter plugged into your (assumedly gas) car. This would allow some lights, charging etc. all for about $100. When the fuel runs low, you just drive to the gas station and fill up.
I have thought about getting a PowerWall as my generator, but they're not rated for being outside (in MN winters), and they're expensive.

Mine were $18k for two, installed, and Tesla handled *everything*. (Outside, in So. CA on existing PV.) You're right, though, -4F on the low end ain't good enough for MN. Come to think of it, +122F on the high end might not be good enough for some other locales, either.
 

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Have a whole house 14kW propane generator that came with my house when I bought it. Rewired it to better align it with what we want on it. Only thing left is to add 3 more tandom breakers to free up 4 slots to add 2 pole 30A breaker for a future heat pump water heater and another 2 pole 20A breaker for an emergency 6-20 plug to charge the car off of it in the event of a power loss. Most loads on this generator our room outlets which are low loads. The heaviest for mine is the well pump and soon to be the water heater. Car will charge at night. Gotta do a load calc one of these days.
 

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The Bolt's DC-DC is max rated to 1600W *at the aux battery*. I've got a 150A fused 120A Anderson connector on the battery, with 10' of #2AWG welding cable extension cord to a 1500W pure sine wave inverter. If I pull any more than about 1000W *from the AC side*, the Bolt's systems can't keep up, and the aux battery voltage will drop to it's ultimate demise.

2200W at 110V AC ain't gonna happen...:eek:

Thank you for this clarifying information. I remember a CA Bolt owner who "ran his house" for 1.5 days at a time when wildfires made his home lose power for > 1 week. I did some rough calculations for the furnace, refrigerator, microwave oven, and several lamps and came up with that 2200 watt number. If I have to settle for only 1000 watts, I will readjust my priorities to accommodate this restriction. Did you make your own 2AWG cable/cord? What connections did you put on it? Did you crimp or solder the connections? How does it fasten to the Bolt battery terminals? Did you mount the inverter on a wooden (3/4" plywood?) board/base? Have you had to use it or is it still in reserve? Do you have to have the Bolt "On"? Does it shut off at 2 hours? Gathering good information BEFORE making any purchases is always a wise course. Thank again.
 

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Thank you for this clarifying information. I remember a CA Bolt owner who "ran his house" for 1.5 days at a time when wildfires made his home lose power for > 1 week. I did some rough calculations for the furnace, refrigerator, microwave oven, and several lamps and came up with that 2200 watt number. If I have to settle for only 1000 watts, I will readjust my priorities to accommodate this restriction. Did you make your own 2AWG cable/cord? What connections did you put on it? Did you crimp or solder the connections? How does it fasten to the Bolt battery terminals? Did you mount the inverter on a wooden (3/4" plywood?) board/base? Have you had to use it or is it still in reserve? Do you have to have the Bolt "On"? Does it shut off at 2 hours? Gathering good information BEFORE making any purchases is always a wise course. Thank again.

See https://www.chevybolt.org/forum/82-charging-batteries/14986-using-bolt-battery-home-emergency-backup.html


My contributions start on page 5, but I recommend that you read the entire thread.
 

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The same solution for:
-Honda EU2000i Generator
-Yamaha EF2000IS
Or other small generators for RV with a floating ground.

Since most of these small generators/inverters uses a "floating neutral," the Model S charger will not work with this generator if connected normally. However, if you short the neutral and ground wires together in the SECOND outlet, using a homemade "pigtail" with the white and green wires connected to each other.

The Honda, Yamaha, Generac, and Predator generators are rated to consume about 1.1 gallons of gasoline when producing 13.3A, and to run for 4-6 hours at this rate without refueling. That means that you will get about 12-18 Miles per gallon of gas depending on your specific generator.
 

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Thought I'd add my recent experience with a Champion generator that we have at a cottage property where we don't have AC yet. It is a model 100463, 7500W 120V/240V gas only model.
First I tried 120V with the stock EVSE since I didn't yet have a twist lock 240V adapter. It didn't work, the EVSE showed a green light but the car said it couldn't charge, the dash light stayed yellow.
When I tried 240V with the stock EVSE it worked fine, at least for 1/2 hour till we ran out of gas!
I ordered an Open EVSE, I'll try that one at 24A when i get it.
29801
 
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