Does anybody know how GM is planning on heating the occupants when the car is run on batteries in the Winter? I assume there will be no waste heat that can be used for windshield defroster and occupant heating. I see old auto heaters on Ebay that are described to be from older cars and i assume burned some type of fuel that i cannot remember.
Mike Healy
Cabin heating in severe cold ambients (<-18) is a bit of an issue. There is no battery that is immune to extremes in temperature. For the battery itself, obviously the 120V charge cycles will assist n keeping it at a higher initial temperature . As far as cabin heating, the use of an electrically powered heat pump and storage via heat "battery" is very likely. Initial ICE operation below a pre-determined threshold is another option.
The Volt's AC Compressor isn't mechanically driven. It runs off the HV battery source. They are currently using a similar compressor on the 2-Mode hybrids that is supplied ~300VDC directly from the hybrid battery where it is inverted to create 3-phase AC to the variable speed AC motor. It is extremely efficient due to it's variable speed that is controlled to match AC load, and is very quiet as well.
WopOnTour
The Volt's AC Compressor isn't mechanically driven. It runs off the HV battery source. They are currently using a similar compressor on the 2-Mode hybrids that is supplied ~300VDC directly from the hybrid battery where it is inverted to create 3-phase AC to the variable speed AC motor. It is extremely efficient due to it's variable speed that is controlled to match AC load, and is very quiet as well.
WopOnTour
How much do you want to pay to be comfortable? You may have to use a little gasoline. Imagine!! My first car did not have a heater at all. You dressed the same as you would if you were going to be outside for that length of time. The first quick heating heater that I saw in a car was from a comapany called South Wind (I believe that was it) It burned gasoline and we were amazed that within a mile you could be reasonably comfortable. Then some engineer figured out if you put a themostatically operated valve in the radiator water flow you could get the engine up to temperature faster and hot enough to heat the car. That has worked for about 60 years now. Do we use the ICE to heat water? (Ha). It may be the most efficient method of heating the car. My first car with A/C was a 1974 model. So for 26 years I survived the heat. Just barely tho when we went to Las Vegas with the bank sign indicating 122F at our arrival. Do you think people would accept a car with a A/C shortfall now or opt for a more frequent operation of the ICE. Nowadays I think they would elect the latter. I know I would. We resolved that after the 122F trip we would never buy another car without A/C.
Can anyone tell me what the first car was that used a thermostat? I have not found a source that gives the date or make.
Can anyone tell me what the first car was that used a thermostat? I have not found a source that gives the date or make.
I am betting that the on-board computers would sense the temperature, and activate the ICE until the battery is warm enough to use in cold temps.
I also have a feeling that the heat to warm the cabin is going to come from the ICE as well, and not tap into the battery.
Just hoping, but I'm sure GM will figure something out. It would be suicide if they only made the Volt to be used in warmer climates...
Canadians want electric cars too!.
I also have a feeling that the heat to warm the cabin is going to come from the ICE as well, and not tap into the battery.
Just hoping, but I'm sure GM will figure something out. It would be suicide if they only made the Volt to be used in warmer climates...
Canadians want electric cars too!.
yeah
Everything I've seen suggests a high efficiency HVAC system. It would be really silly to use anything else from an efficiency and practicality standpoint. It'd be very silly to have to run the motor to use either given the very nature of the car. As far as I've read the only time the motor runs besides after the battery is depleted is to initially warm the battery from a cold start in very cold climates so that it functions properly.
Everything I've seen suggests a high efficiency HVAC system. It would be really silly to use anything else from an efficiency and practicality standpoint. It'd be very silly to have to run the motor to use either given the very nature of the car. As far as I've read the only time the motor runs besides after the battery is depleted is to initially warm the battery from a cold start in very cold climates so that it functions properly.
Guys, I'm the guy that drives the RAV4 EV. It has the following cold-weather features:
-Heat Pump and A/C: It's the same system, but runs in reverse for heat. The A/C is less of a drain on the battery than the heat. The reason for this is that heat pumps lose their effciency as the outside temp falls. Both systems are quite powerful, the heat will toast you and the A/C will freeze you. The RAV4 has quite a large cabin, and the sun is brutal here in summer and the winter is bitter cold. The air is also very dry, so it doesn't store heat very well. The RAV4 also has clear glass so the solar gain is brutal as well (soon to be rectified with aftermarket tint). The point is that electric-driven heat-pump and A/C can keep up quite well with conditions without huge strains on the battery.
-Heated seats: Hi and Lo, works great
-Rear defroster: standard, but on a timer
-Heated windshield: The inner layer between the glass sandwich is heated. Very, very neat. Melts ice and snow directly with no air blowing.
-Pre-heat and pre-cool on shore power: Very nice. Set the timer, and the car will be heated and cooled from the wall, leaving you ready to drive with a full battery.
Just a side note, cold and snowy or wet weather has other range implications. The heat pump is a piece of it. I believe I've listed all of them in another thread.
So, to answer the question, a car can be fully heated and cooled without burning anything, in fact, the heated windshield is awesome.
Nate
-Heat Pump and A/C: It's the same system, but runs in reverse for heat. The A/C is less of a drain on the battery than the heat. The reason for this is that heat pumps lose their effciency as the outside temp falls. Both systems are quite powerful, the heat will toast you and the A/C will freeze you. The RAV4 has quite a large cabin, and the sun is brutal here in summer and the winter is bitter cold. The air is also very dry, so it doesn't store heat very well. The RAV4 also has clear glass so the solar gain is brutal as well (soon to be rectified with aftermarket tint). The point is that electric-driven heat-pump and A/C can keep up quite well with conditions without huge strains on the battery.
-Heated seats: Hi and Lo, works great
-Rear defroster: standard, but on a timer
-Heated windshield: The inner layer between the glass sandwich is heated. Very, very neat. Melts ice and snow directly with no air blowing.
-Pre-heat and pre-cool on shore power: Very nice. Set the timer, and the car will be heated and cooled from the wall, leaving you ready to drive with a full battery.
Just a side note, cold and snowy or wet weather has other range implications. The heat pump is a piece of it. I believe I've listed all of them in another thread.
So, to answer the question, a car can be fully heated and cooled without burning anything, in fact, the heated windshield is awesome.
Nate
Yes, the seats are heated resistively. Nothing special there, not really much amp draw. The heat pump is biggest draw. Most days, if it's cold but not snowing (say, about 35-40 degrees out) you can pre-heat the cabin from shore power, then turn on the heated seats and windshield and drive with the heat pump on low or turned off and see almost no noticeably effect on range.
If you drop frozen water on the car the whole trip (like snow) you need more heat to melt it off, so the heat pump is a must. You start to feel the range drop, and it gets bad when it's very cold, snowy, wet, dark, and windy. The range can drop by almost 30-40%.
Nate
If you drop frozen water on the car the whole trip (like snow) you need more heat to melt it off, so the heat pump is a must. You start to feel the range drop, and it gets bad when it's very cold, snowy, wet, dark, and windy. The range can drop by almost 30-40%.
Nate
From an Engineering View Point, Resistive and Heat Pump is a Mistake
From an engineering view point, resistive loads and heat pump are a mistake for controlling temperature on very cold Winter days. Sure, resistive and heat pumps are easy to engineer and implement, but they are wasteful of electric power. Cold weather is the most demanding for a storage battery. Adding resistive loads and heat pumps (heat pumps are terribly inefficient in cold weather) would further burden the storage battery. Batteries are at their lowest potential for storing power in cold weather. Direct conversion of gasoline into heat is the answer. Burning gasoline was used for years in automobiles before waste heat from the engine coolant was recovered to temper the passengers. The burning gasoline (or other fuel) can also be used to warm the batteries on the cold morning start ups.
From an engineering view point, resistive loads and heat pump are a mistake for controlling temperature on very cold Winter days. Sure, resistive and heat pumps are easy to engineer and implement, but they are wasteful of electric power. Cold weather is the most demanding for a storage battery. Adding resistive loads and heat pumps (heat pumps are terribly inefficient in cold weather) would further burden the storage battery. Batteries are at their lowest potential for storing power in cold weather. Direct conversion of gasoline into heat is the answer. Burning gasoline was used for years in automobiles before waste heat from the engine coolant was recovered to temper the passengers. The burning gasoline (or other fuel) can also be used to warm the batteries on the cold morning start ups.
GM implemented a fuel heater in their EV S-10 pickup. It takes about 1.5 gallons of various fuels, typically diesel, and is catalytic (no burning). It consumed about 1.5 gallons per year, not bad. Also, GM had a sensor so the heat pump would run when it was brisk but the catalytic heater would run when it was very cold out.
Some RAV4 EV owners have reported using one of these
http://www.amazon.com/Coleman®-Powermate®-12V-Ceramic-Heater/dp/B0001YWH6U
and getting better range than the heat pump.
As long as I get home on my battery, I don't really care how much juice gets used up on cold days. My commute is 38 miles round trip, so only having 60 miles on an uber-cold and snowy day is not much to worry about.
The "range worry" is called "plug anxiety" and it goes away after driving an EV for a while. Strangely, the urge to buy gasoline lasts a bit longer. There is a strange habit that all of you have that you aren't aware of: When you drive by a gas station, you check the gas gauge to see if you need to fill up. The impulse to do this is stronger if you can't remember the last time you bought gas. This impulse was with me for months, since I never had the recent memory of buying gas. This impulse, gasoline anxiety, finally went away after about 6 months.
Man, I wish I lived in Atlanta right now, it would be easy to show the media the benefit of plugging in.
Nate
Some RAV4 EV owners have reported using one of these
http://www.amazon.com/Coleman®-Powermate®-12V-Ceramic-Heater/dp/B0001YWH6U
and getting better range than the heat pump.
As long as I get home on my battery, I don't really care how much juice gets used up on cold days. My commute is 38 miles round trip, so only having 60 miles on an uber-cold and snowy day is not much to worry about.
The "range worry" is called "plug anxiety" and it goes away after driving an EV for a while. Strangely, the urge to buy gasoline lasts a bit longer. There is a strange habit that all of you have that you aren't aware of: When you drive by a gas station, you check the gas gauge to see if you need to fill up. The impulse to do this is stronger if you can't remember the last time you bought gas. This impulse was with me for months, since I never had the recent memory of buying gas. This impulse, gasoline anxiety, finally went away after about 6 months.
Man, I wish I lived in Atlanta right now, it would be easy to show the media the benefit of plugging in.
Nate
Please remember, the Volt will have a pre conditioning setting. Meaning you can cool down the cabin with AC, or have it nice & toasty before you get in all while still plugged in, so you can drive away in your pre heater/chilled car with a full battery. That will greatly reduce the draw on the battery and overall range as getting the initial cooling/heating of the interior takes the most energy, maintaining that temperature once achived isn't that hard.
If the engine runs every so often, will it really be THAT bad? Be sure to use E85 if available to really reduce your oil dependency, assuming E85 is available to you.
If the engine runs every so often, will it really be THAT bad? Be sure to use E85 if available to really reduce your oil dependency, assuming E85 is available to you.
A conventional car will get slightly worse fuel economy in the winter then the summer.
Cold temperatures require a slightly richer fuel mixture.
Oil is thicker
Air is more dense
Thermostats are used to allow heat to build up in the engine. (usually to 200 degrees.)
The heat is a byproduct of running.
an Electric car will have a Heat byproduct as well, but in much smaller amounts then a gas engine.
This leads to the need for aux heating.
1kWh = 3413 BTU of heat.
Instead of directly converting energy to heat, a heat-pump can be used. This extracts heat from an existing medium using a gas at low pressure in a closed loop. The gas is then compressed to create the hot side.
This method can be much more efficient assuming heat is out there to be picked up.
In extremely cold weather, there might not be enough heat for this method to work.
Air Conditioning is provided using the same method but with the de-pressurized side of the loop going to the cabin (providing the cooling.) (i.e. heat is being pumped OUT of the cabin into the environment.)
If I were to brainstorm "what would use the least energy" - I guess I would have to recommend something like a heat lamp.
Sure a 1000w heat lamp uses the same as much power as a 1000w electric heater, and both provide the same BTU, but a greater portion of the heat provided would make it to the occupant using the lamp.
In the end, I would rather heat the entire cabin - screw the efficiency... but yea...
Cold temperatures require a slightly richer fuel mixture.
Oil is thicker
Air is more dense
Thermostats are used to allow heat to build up in the engine. (usually to 200 degrees.)
The heat is a byproduct of running.
an Electric car will have a Heat byproduct as well, but in much smaller amounts then a gas engine.
This leads to the need for aux heating.
1kWh = 3413 BTU of heat.
Instead of directly converting energy to heat, a heat-pump can be used. This extracts heat from an existing medium using a gas at low pressure in a closed loop. The gas is then compressed to create the hot side.
This method can be much more efficient assuming heat is out there to be picked up.
In extremely cold weather, there might not be enough heat for this method to work.
Air Conditioning is provided using the same method but with the de-pressurized side of the loop going to the cabin (providing the cooling.) (i.e. heat is being pumped OUT of the cabin into the environment.)
If I were to brainstorm "what would use the least energy" - I guess I would have to recommend something like a heat lamp.
Sure a 1000w heat lamp uses the same as much power as a 1000w electric heater, and both provide the same BTU, but a greater portion of the heat provided would make it to the occupant using the lamp.
In the end, I would rather heat the entire cabin - screw the efficiency... but yea...
I had heated leather seats in my Audi. Those were cool and all, but cranking it up to the point of burning your behind and back while the rest of you is cold is about as comfortable as it sounds.
Possibly. I mean it wouldn't hurt. Might as well put the ICE 'waste' to good use (heating.) as it shouldn't affect figures much
Catch being why use gas when you don't need to. Kinda defeats the point of going EV.
It's a topic I'm definately interseted in. I live in Northern MN, and like Omnimoeish pointed out; heating just your seat isn't exactly the most comfortable experience.
And while the Electric motor probably benifits from the cold, are the battery packs really that sensitive to temperature?
I beleive the freezing point of Li Ion would be around -76F (-60c)
Obviously the batteries are affected before reacing that temperature, but by how much? I really have no idea...
Catch being why use gas when you don't need to. Kinda defeats the point of going EV.
It's a topic I'm definately interseted in. I live in Northern MN, and like Omnimoeish pointed out; heating just your seat isn't exactly the most comfortable experience.
And while the Electric motor probably benifits from the cold, are the battery packs really that sensitive to temperature?
I beleive the freezing point of Li Ion would be around -76F (-60c)
Obviously the batteries are affected before reacing that temperature, but by how much? I really have no idea...
Just a note to nater: Congrats on the RAV4 I kind of wanted one so I could drive off my 2.2KW solar PV system we are installing. Coolcar even though it's NiMHi. and good range. Just wondered if your on:
http://www.evnut.com/rav_owner_gallery.htm
Congrats.
PS where do you live w/ such harsh condition. Most of these are in So CA.?
http://www.evnut.com/rav_owner_gallery.htm
Congrats.
PS where do you live w/ such harsh condition. Most of these are in So CA.?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
