Improvements to the climate control.

[jeffand]

Driving in the cold weather does cause a big hit in range. Ford needs to address this issue.
Here are sugestions on how to reduce the energy usage by the climate control.
Convert the air conditioning to a heat pump.
Use a air to air heat exchanger, to recover lost heat. Heat or coolness can be recovered from vented air and used to condition the incoming air.
The problem is that climate control uses two 5000 watt heaters. If you are using the defroster you are also using the air conditioner to dry the air also.

 

[michael]

I'd settle for the heat pump. That alone would do most of the job. The present system is horrible!!

At present, it can use something in excess of 5 KW (the gauge hits max at 5 KW), or more than 5 kWh/hour. At 40 MPH and 250 Wh/mile, average consumption is 10 kW. So in this example, the heater alone uses half of what is used to propel the car.

Wasteful, wasteful, wasteful!

 

[WattsUp]

I'd settle for the heat pump. That alone would do most of the job. The present system is horrible!!

At present, it can use something in excess of 5 KW (the gauge hits max at 5 KW), or more than 5 kWh/hour. At 40 MPH and 250 Wh/mile, average consumption is 10 kW. So in this example, the heater alone uses half of what is used to propel the car.

Wasteful, wasteful, wasteful!

I'm not sure what you meant, but the expression "5 kWh/hour" doesn't make any sense. I think you meant simply "5 kWh" (which is a measure of energy). Specifically, 5 kWh is an expression that means "the energy required to sustain a rate of consumption of 5 kW for 1 hour".

Yes, the climate can consume 5 kW (or more) at any given instant, but it would have to do so continuously for 1 hour in order to consume 5 kWh of energy. In reality, the climate modulates its rate of consumption. Once the cabin has been heated, the rate can drop significantly below 5 kW. (Unless, of course, the car is is extreme cold.)

I'm not saying the heater couldn't be more efficient, just clarifying what we're talking about.

 

[sefs]

I wish the heater could use less energy, but I believe its power level is absolutely necessary. During my commute on a few near 0F days this year, in particular yesterday, in a 30 minute ride home the car never got to a fully warm temperature. The climate was pegged at 5kW+ the whole way. Maybe a heat pump would be nice for the more mild days, but in the cold weather we get here (Southwest PA), it just wouldn't cut it.

Just as an aside, when I initially read about the car having a resistive heater, I thought it was configured just like a space heater with resistive coils having air blown over them. However, through learning more about the car, I learned that there is actually a liquid coolant loop for the cabin heat, just like in the ICE Focus. The key difference is that there is a submerged resistive heater in the coolant loop instead of the coolant running through the engine. Also, this coolant loop has valves to connect it to the coolant loop for the propulsion inverter and the motor, as well as the coolant loop for the batteries and charger. I'm not sure what the behavior of the valves are, but there are interconnects there. Finally (maybe others knew this), the battery heater does not run unless the car is plugged in. It is comprised of three 300W "glow plugs" in series with the battery and charger coolant loop. However, the battery will use the chiller to cool itself while driving and not plugged in.

 

[rabar10]

However, through learning more about the car, I learned that there is actually a liquid coolant loop for the cabin heat, just like in the ICE Focus. The key difference is that there is a submerged resistive heater in the coolant loop instead of the coolant running through the engine. Also, this coolant loop has valves to connect it to the coolant loop for the propulsion inverter and the motor, as well as the coolant loop for the batteries and charger. I'm not sure what the behavior of the valves are, but there are interconnects there. Finally (maybe others knew this), the battery heater does not run unless the car is plugged in. It is comprised of three 300W "glow plugs" in series with the battery and charger coolant loop. However, the battery will use the chiller to cool itself while driving and not plugged in.

I had seen earlier references to the resistive heater actually heating an oil or coolant fluid, thanks. What's your source of info for these details on the heat/coolant circuits?

 

[sefs]

I had seen earlier references to the resistive heater actually heating an oil or coolant fluid, thanks. What's your source of info for these details on the heat/coolant circuits?

The service manual for the Focus Electric has all of these details. Also, the service training program gives a nice overview of all the system operations.

 

[michael]

I'd settle for the heat pump. That alone would do most of the job. The present system is horrible!!

At present, it can use something in excess of 5 KW (the gauge hits max at 5 KW), or more than 5 kWh/hour. At 40 MPH and 250 Wh/mile, average consumption is 10 kW. So in this example, the heater alone uses half of what is used to propel the car.

Wasteful, wasteful, wasteful!

I'm not sure what you meant, but the expression "5 kWh/hour" doesn't make any sense. I think you meant simply "5 kWh" (which is a measure of energy). Specifically, 5 kWh is an expression that means "the energy required to sustain a rate of consumption of 5 kW for 1 hour".

Yes, the climate can consume kW (or more) at any given instant, but it would have to do so continuously for 1 hour in order to consume 5 kWh of energy. In reality, the climate modulates its rate of consumption. Once the cabin has been heated, the rate can drop significantly below 5 kW. (Unless, of course, the car is is extreme cold.)

I'm not saying the heater couldn't be more efficient, just clarifying what we're talking about.

Right, I totally understand that. I'm an EE as you apparently are. kW is power and kWh is energy. But 5 kW is 5 kWh/h. That does make sense and it's dimensionally correct. If I had said 5 kW is 120 kWh/day or 0.83 kWh/minute it would be equally correct. I was making that point to relate to the 10 kWh/h that the car consumes at 250 Wh/mile * 40 mi/h. In an hour the drive train consumes 10 kWh, and the heater consumes 5+ kWh.

It would have been equally correct (and in retrospect maybe clearer) to say that the heater consumes 5+ kW, and that at 40 mi/h and 250 Wh/mi the car consumes 10 KW average.

But in one way or the other, one can't compare kW to Wh/mi without converting both to some common units under stated conditions (in my example, 40 mph which I thought representative of cold weather driving on typical roads).

And I think we both agree the heater is a major power draw. When I'm about to park the car for several days and want to deplete the battery slightly beforehand, I just run the heater for an hour at full tilt. Runs the battery down by 20% without driving.

And as Sef's points out, in cold weather the heater does run continuously at 5+ kW

 

[WattsUp]

If I had said 5 kW is 120 kWh/day or 0.83 kWh/minute it would be equally correct. I was making that point to relate to the 10 kWh/h that the car consumes at 250 Wh/mile * 40 mi/h. In an hour the drive train consumes 10 kWh, and the heater consumes 5+ kWh.

Yes, correct. I get what you were doing now... you were referencing an actual hour (e.g., using 10 kWh of energy over 1 hour of elapsed time) to compare driving at 40 mph versus running the heater at full blast.

With the rate that people get confused between kW and kWh, and the fact that the "hour" in watt-hours doesn't necessarily refer to actual elapsed time, I felt an urge to "correct" you. People often say things like, "I fully charged my car and it used 23 kW", or, "I drove to my mom's house and only used 200 watts per mile!" (I think they conclude the "Wh" in Wh/mi label on the display must be short for "whatts").