Heater = 9kW

[devbolt]

Has anybody tried measuring what the draw is from the wall when using preconditioning? That might help answer the question. If you have a smart meter that shows what your current draw is for the house, it should be pretty easy to determine what the draw is for the car when you activate preconditioning. I would be curious to know what it is for both 240V and 120V.

 

[LeftieBiker]

Has anybody tried measuring what the draw is from the wall when using preconditioning? That might help answer the question. If you have a smart meter that shows what your current draw is for the house, it should be pretty easy to determine what the draw is for the car when you activate preconditioning. I would be curious to know what it is for both 240V and 120V.

The temperature should be a constant.

 

[SeanNelson]

Has anybody tried measuring what the draw is from the wall when using preconditioning?

It should be pretty close to what the car's power meter shows when you're running an equivalent HVAC load off the battery. So if you're using preheat and the heater draws 6KW off the battery, then preconditioning while plugged in should be pulling close to 6KW from the wall (assuming that the battery is fully charged and that no power is going into charging it). 6KW at 240V would be 25A. (6000W / 240V = 25A).

If you're running at 120V then the 12A current limit means you top out at 1.44KW, so that might throttle how much heat you could put into the cabin (or it might mean that you're getting most of the power out of the battery even though you're plugged into the wall).

 

[summit]

The sad thing is that the heatpump is already installed as an AC. It just needs a couple of valves and some control relays to operate an AC as a heatpump for heat.

Another potential advantage employing a heatpump for heat is to use excess heat from motor/battery, instead of just dumping out the radiator.

 

[michael]

The sad thing is that the heatpump is already installed as an AC. It just needs a couple of valves and some control relays to operate an AC as a heatpump for heat.

Another potential advantage employing a heatpump for heat is to use excess heat from motor/battery, instead of just dumping out the radiator.

I agree. This is sort of in the "there's no excuse" zone especially if it were an extra cost option for those who don't care.

 

[devbolt]

I figured that the max draw from the wall at 240V would be close to the 7.2 kW max of a 30A EVSE and that on 120V you'd only get a max of 1.44 kW.

I'll have a chance to test this this weekend after I pickup my Bolt finally...

 

[LeftieBiker]

It's funny. I've been bugging Toyota for years, through the Prius PHEV owners surveys, to install a heatpump, but was expecting at most a resistance heater. It turns out they did give the 25 mile EV Prime a heatpump, but the Bolt will be burning electrons for heat the old fashioned way...

 

[like2bike]

Sorry for the low LEAF heating power numbers. I realized now that they must be off by like a factor of 2. I checked the pre-heat power from my EVSE and it is 6.5 KW. The pre-heat blasts the heat, so I didn't wait to see if the power comes down eventually. I have checked the KWH for pre-heating before and realized it is quite expensive at the ludicrous LI, NY electric rates. Consequently, I only use it in extreme cold and set the departure time later than the planned departure.

BTW, I have a meter added to my EVSE for KW/KWH/V. Here are the details if anyone is interested: http://like2bike.myevblog.com/sample-page/adding-a-kwh-meter-to-an-evse/

I am not convinced a heat pump is cost effective. I was told by a CAC guy that the valves needed shorten the life of the heat pump. I will check on the LEAF forum to see whether their heat pumps are lasting.

 

[michael]

Being "cost effective" is not the issue in my mind. The issue is whether running the stupid heater torpedoes the range. I'm willing to pay extra to be able to run the heater without worry.

 

[LeftieBiker]

I will check on the LEAF forum to see whether their heat pumps are lasting.

Four years after the introduction of the heatpump in Leaf SV and SL models there are no reports of heat pumps wearing out or failing in significant number. Ironically, the resistance heater is more prone to failure.

 

[devbolt]

I figured that the max draw from the wall at 240V would be close to the 7.2 kW max of a 30A EVSE and that on 120V you'd only get a max of 1.44 kW.

I'll have a chance to test this this weekend after I pickup my Bolt finally...

Max draw from the wall when pre-conditioning is indeed the max that the EVSE can provide. However, the car will consume any additional power it needs from the battery pack to heat or cool the car. I saw 7.35 kW being drawn from the wall (30A at 245V = 7350 watts), and an additional 2 or so kW being drawn from the battery pack when I had the heat turned up to max. If I had the heat turned down to a more reasonable level like 75, the car only pulled what was absolutely necessary, which was somewhere between 3 and 4 kW.

I did not test power draw when using the portable 120V EVSE. I'll have to try that some other time.

 

[sgt1372]

Just a "thank-you" from this new Bolt leasee for the tip about using the heated steering wheel and seat(s) to save on the battery drain.

 

[samiam95124]

Resistance heating is the least efficient heating possible. Its why those cheap Home Depot heaters really wreck your power bill if you use them all winter. For whats its worth, I had a leaf, and that heater (heat pump) was finicky as hell, it seemed to work for a while then make up its own mind about what temperature it wanted, leading me to always turn it either to max or off.

You paid extra for a car with enough battery capacity to power your house for the day. I recommend you turn on sport mode, blast the heater and the radio and enjoy. Worry about too much power draw if you are on a long trip with no chargers in sight. Otherwise forget about it.

 

[samiam95124]

Four years after the introduction of the heatpump in Leaf SV and SL models there are no reports of heat pumps wearing out or failing in significant number. Ironically, the resistance heater is more prone to failure.

Yep, having a metal ribbon heat from abient temperature to several hundred degrees and back regularly fatigues the metal quite rapidly.

 

[EldRick]

...from ambient temperature to several hundred degrees and back...

I'd be really surprised if it heats to more than 230F, as it is immersed in coolant.

 

[oilerlord]

I agree. This is sort of in the "there's no excuse" zone especially if it were an extra cost option for those who don't care.

Yup.

I'm installing an Airtronic D2 cabin heater as an "extra-cost option" in my EV because I'm not going to freeze my ass off again next winter in the effort to preserve range.

I'm also hooking it up with a GSM relay so I can send a text message to turn it on and off. All told, I'll be into it for about CDN$1000.

 

[phil0909]

I'm installing an Airtronic D2 cabin heater as an "extra-cost option" in my EV because I'm not going to freeze my ass off again next winter in the effort to preserve range.

Well, 8 watts (or even 34) is definitely less than 9,000 watts.

 

[oilerlord]

Well, 8 watts (or even 34) is definitely less than 9,000 watts.

It is.

The diesel heater won't be an easy installation, the location of the heat vent being one of the biggest challenges. I want the car to be warm, but I also don't want the windows to fog either. If It could be hooked up to use the factory vents, that would be ideal. The hydronic model works with the existing ducting for cars equipped with a heater core, but my EV doesn't have one, and I wouldn't want to tap into the coolant reservoir at risk of cooking the battery.

The Bolt's 9kW heater is a huge load but probably not a big deal if you rarely use it. Here in Alberta, the heater is as important as AC is for people that live in Arizona. If GM really does have plans to sell the Bolt in all 50 states - there really is no excuse the car didn't come with a heat pump. Perhaps that's coming on Bolt V2.0.

The good news is I have all summer to figure this out. I'll post pictures after it's installed.

 

[michael]

Well, 8 watts (or even 34) is definitely less than 9,000 watts.

It is.

The diesel heater won't be an easy installation, the location of the heat vent being one of the biggest challenges. I want the car to be warm, but I also don't want the windows to fog either. If It could be hooked up to use the factory vents, that would be ideal. The hydronic model works with the existing ducting for cars equipped with a heater core, but my EV doesn't have one, and I wouldn't want to tap into the coolant reservoir at risk of cooking the battery.

The Bolt's 9kW heater is a huge load but probably not a big deal if you rarely use it. Here in Alberta, the heater is as important as AC is for people that live in Arizona. If GM really does have plans to sell the Bolt in all 50 states - there really is no excuse the car didn't come with a heat pump. Perhaps that's coming on Bolt V2.0.

The good news is I have all summer to figure this out. I'll post pictures after it's installed.

I so agree with you about the lack of heat pump. That is such a cheapening of the car. Believe me, even in California it's a big deal.

 

[phil0909]

Believe me, even in California it's a big deal.

Really? I live in California, and never use heat. Not even a little deal for me.

I could see how it's important for Siberians, though.