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garygid
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Re: climate control on L1 charging?

Fri Sep 03, 2010 4:22 pm

I agree, I suspect the following:

1. The car's heating and A/C are designed to work using DC.
2. The main heater probably uses the high voltage DC (from the main "traction" battery), to minimize currents and conversion losses.
3. The A/C probably does the same, but uses noticably less power.
4. The seat/steering wheel heater, if we have it, will use the 12-volt system, for safety. But, the 12-volt system gets all of its energy "through" the main traction battery, via a DC-to-DC converter (unless one has the PV panel, and it is adding energy to a non-full 12v battery).
5. Most likely, the only path for AC energy to enter the car will be through the current-limited charger, either 1.4 or 3.3 kW, and the charger will convert that, if needed, to high-voltage DC in an attempt to charge the traction battery, or POSSIBLY to "maintain" a given charge level.
6. The internal charger MIGHT also supply some DC energy when the battery is already "charged", and the requested pre-heat/cool begins, in an attempt to keep the battery from discharging. Of course, it could not if the EVSE was OFF, unplugged, or "timed out".

So, I suspect that the pre-heat/cool WILL use whatever energy it needs from the traction battery, and a powered charger COULD try and supply some (or much) of the energy, and that the pre-heat/cool will (MAYBE, probably) work, using the main battery, even if the car is NOT plugged in.

My 5¢ worth.
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tps
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Re: climate control on L1 charging?

Sat Sep 25, 2010 8:10 am

My company deals with preheat and precool, not in cars, but in commercial buildings. Some of the major factors, which will be a bit different when it comes to cars are:

1. Thermal mass - the amount of heat or cold that is "stored" in the mass of the interior of the space, probably lower in a car
2. Insulation resistance - likely to be lower in a car and thus more loss to the ambient temp outside
3. Solar radiation - This is helps preheat and hurts precool (during the day).
4. Outside air temp - the more temperature differential accross the insulation resistance, the more the losses will be
5. Off peak electricity cost - likely insignificant in car preheat / precool since the small thermal mass and low insulation resistance would preclude long term thermal storage.

All said, I would expect preheat / precool to give some small range advantage because it could "charge up" the small thermal mass of the car while it was on AC power. If the car was disconnected and driven away immediately before the thermal mass had a chance to discharge through the insulation resistance, maybe one would get a slight advantage.

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garygid
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Re: climate control on L1 charging?

Sat Sep 25, 2010 8:56 am

Paying for an "edie" (kWh) or two occasionally to get into a comfortable car ... would be a nice feature, though not often needed around here.
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2010 Prius, now for sale
2011 LEAF, sold in 2015
2018 Tesla Model 3
2014 Tesla S, Model 3 in 2019
PU: SDG&E
Solar PV: 33 x 225W -> 7 kW max AC
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Herm
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Re: climate control on L1 charging?

Tue Nov 02, 2010 6:51 pm

The AC uses up to 600W, from one of the economy displays in the LEAF. Does anyone know if the AC can also work as a heat pump, to provide heat in moderate climates?

JasonT
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Location: AZ

Re: climate control on L1 charging?

Tue Nov 02, 2010 9:54 pm

Herm wrote:Does anyone know if the AC can also work as a heat pump, to provide heat in moderate climates?
It can not. The heater is separate and uses more power than the AC

danwat1234
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Re: climate control on L1 charging?

Sun Nov 14, 2010 9:29 pm

I have heard from another thread on this website that the heater is a resistive heater, not a heat pump.
Power consumption of the heater can get up to around 5,000 watts, according to this video I made.
http://www.youtube.com/watch?v=Apaf7nGXZt8
The temperature is set to 90 F and the fan is turned up about 3/4 of the way. At 45 seconds you can see the power consumption rising above 4500 watts.

A bit later in the video I keep the temperature setting at 90 F, but I turn down the fan speed but the power consumption stay above 1500 watts.
My video pretty much confirms this as I doubt a car heatpump with a variable speed compressor would take more than 2000 watts max.


So I would have to assume that the climate control system (heater, fan and air conditioner systems) are powered thru the battery pack but the pack can also be receiving juice from a charger at the same time..

DaveinOlyWA
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Re: climate control on L1 charging?

Sat Feb 12, 2011 3:25 pm

anyone figure out what the power draw would be for the A/C yet? under a 1000 watts seems a bit too low.
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 deceased. 29,413 miles. 2018 S40; 15,000 miles, 478 GIDs, 37.0 kwh 109.81 Ahr , SOH 94.61, Hx 120.15
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AndyH
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Re: climate control on L1 charging?

Sat Feb 12, 2011 4:26 pm

danwat1234 wrote:I have heard from another thread on this website that the heater is a resistive heater, not a heat pump.
Power consumption of the heater can get up to around 5,000 watts, according to this video I made.
http://www.youtube.com/watch?v=Apaf7nGXZt8
The temperature is set to 90 F and the fan is turned up about 3/4 of the way. At 45 seconds you can see the power consumption rising above 4500 watts.

A bit later in the video I keep the temperature setting at 90 F, but I turn down the fan speed but the power consumption stay above 1500 watts.
My video pretty much confirms this as I doubt a car heatpump with a variable speed compressor would take more than 2000 watts max.


So I would have to assume that the climate control system (heater, fan and air conditioner systems) are powered thru the battery pack but the pack can also be receiving juice from a charger at the same time..

According to the service manual, the Leaf heater is a 5kW total unit made up of four elements, all under computer control. Heater power is modulated (PWM) so heat control is not simply 'turn on element 1, now turn on element 2'.

DaveinOlyWA
Posts: 13870
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Delivery Date: 16 Feb 2018
Leaf Number: 314199
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Contact: Website

Re: climate control on L1 charging?

Sat Feb 12, 2011 7:21 pm

nothing on how much power A/C uses?
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 deceased. 29,413 miles. 2018 S40; 15,000 miles, 478 GIDs, 37.0 kwh 109.81 Ahr , SOH 94.61, Hx 120.15
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Caracalover
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Re: climate control on L1 charging?

Sat Oct 29, 2011 4:53 pm

danwat1234 wrote:I have heard from another thread on this website that the heater is a resistive heater, not a heat pump.
Power consumption of the heater can get up to around 5,000 watts, according to this video I made.
http://www.youtube.com/watch?v=Apaf7nGXZt8
The temperature is set to 90 F and the fan is turned up about 3/4 of the way. At 45 seconds you can see the power consumption rising above 4500 watts.

A bit later in the video I keep the temperature setting at 90 F, but I turn down the fan speed but the power consumption stay above 1500 watts.
My video pretty much confirms this as I doubt a car heatpump with a variable speed compressor would take more than 2000 watts max.


So I would have to assume that the climate control system (heater, fan and air conditioner systems) are powered thru the battery pack but the pack can also be receiving juice from a charger at the same time..

Had to laugh out loud when you were talking about the controls. The dial next to the speaker switch is not for volume control, but headlight aim. The other one is traction control.
26,000 miles on Silver Leaf
wildcatzoo.org drive there on Sunday across a big mountain, sorry no public charging at this time.
Looking for grants to put in solar port so perhaps in the future...

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