I probably should have said system instead of loop. The interior loop is only for cooling.
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I probably should have said system instead of loop. The interior loop is only for cooling.
iwannam3
Active Member
For total hearsey you could use a diesel fired Espar hydronic heater like in my Mercedes Sprinter Westfalia RV. You can preheat the engine with it, it circulates coolant through the engine block. There is a second one to heat the interior of the RV. They even have a small catalytic converter attached. Truckers use them to heat the cab when the engine is not operating, Diesel boats and sail boats use them also. Burn bio-diesel for that french fry smell......
We have a couple of the small heat pumps here that heat/cool two rooms upstairs. One is an office on the SW side of the house that is an oven in the summer due to being upstairs, in full sun, and with computers running. The other is in the master bedroom.
On very cold mornings I start the heat pump in the bedroom with the remote before getting out of bed. I've found when temps outside are around 40F or higher, it starts heating in a few minutes. When temps are down in the low 30s or lower, it takes significantly longer for the heat to kick in. We're having another cold snap now and it took about 1/2 hour this morning.
A lot of new heat pump tech has come along in recent years. The new individual room wall units are very different from the old heat pumps. Heat pumps are still rare in cars. Tesla probably figures that by the time a heat pump would kick in, the battery would be warm and their system for harvesting excess heat from the battery cooling system is even more efficient than a heat pump would be.
While the passenger cabin of the Leaf and Model S are similar in size, the cargo area in the S is much bigger and the space is connected to the passenger cabin, so it needs to be heated too. I am not that familiar with the Leaf (never actually been in one), but I would estimate the volume that needs to be heated is probably about 50% larger in the Model S and even larger in the Model X. The passenger space in the S seems smaller than it is because the roof is lower than most large sedans.
I've found the heat to be very effective with Range Mode off.
On very cold mornings I start the heat pump in the bedroom with the remote before getting out of bed. I've found when temps outside are around 40F or higher, it starts heating in a few minutes. When temps are down in the low 30s or lower, it takes significantly longer for the heat to kick in. We're having another cold snap now and it took about 1/2 hour this morning.
A lot of new heat pump tech has come along in recent years. The new individual room wall units are very different from the old heat pumps. Heat pumps are still rare in cars. Tesla probably figures that by the time a heat pump would kick in, the battery would be warm and their system for harvesting excess heat from the battery cooling system is even more efficient than a heat pump would be.
While the passenger cabin of the Leaf and Model S are similar in size, the cargo area in the S is much bigger and the space is connected to the passenger cabin, so it needs to be heated too. I am not that familiar with the Leaf (never actually been in one), but I would estimate the volume that needs to be heated is probably about 50% larger in the Model S and even larger in the Model X. The passenger space in the S seems smaller than it is because the roof is lower than most large sedans.
I've found the heat to be very effective with Range Mode off.
Tesla does not harvest heat from the battery for the cabin. It does use motor heat to heat the battery.
And in really cold climates the battery doesn't even really get warm enough to need cooling. (At least that is my understanding.)
I guess my error was in thinking they actually implemented the patent they have for the heating/cooling system.
Heat-Pump Cabin Heater
The leaf has passive battery cooling and a battery heater for extreme cold. It seems to work just fine. I don't expect 20 years from my leaf but 10 would be nice. I need at least 10 from the S for it not to be a giant waste of money. Tesla clearly has better battery engineering to make that 10 more likely but I'd like to see them incorporate a heat pump or at least what they outlined in the post by @wdolson
Sir Guacamolaf
The good kind of fat
Canuck
Well-Known Member
No, it doesn't work at all. It's okay for cooler climates but in hotter climates the batteries degrade rapidly, hence the Nissan Leaf Battery Capacity Lawsuit: Court Approves Settlement.
Tesla has repeatedly said that the buyers of S and X vehicles are funding the Model 3. I don't consider that a waste of money at all regardless of how long I keep my vehicle.
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Wow, such hate. Nissan changed its battery chemistry and so it isn't really as big of an issue. Anyways, this thread isn't on active vs. passive battery cooling, its on heat and how Tesla could improve efficiency for those of us in colder areas by changing the current design (and using their own patented one or another manufacturer's established design). Nissan is just one manufacturer of BEV that has a proven heating design that I like.
Incredulocious
LEAF → RAV4EV → Model 3 → Model Y
Actually Nissan originally made the LEAF without a heat pump (just resistive heating) and then added a heat pump in later LEAF models to improve its efficiency.
Have to disagree on all but the " more complex" part. A heat pump does not weigh significantly more than the existing air conditioner, and modern heat pumps work fine at low temperatures, though obviously not as much of an efficiency gain. And there would still be the resistance heater when needed, most likely.
Yes, significantly. My leaf only draws 1.1kw when heating up and around 600w after it reaches temp (peak possible draw is around 3 or 3.5 kw though). I also put it at a higher temp than my S. Apparently older leafs used about 3x that energy and put out less heat. Its quite unfortunate the S doesn't incorporate better tech in its heating.
FWIW, my LEAF will also use shore power to preheat the cabin just like the S, so it can avoid the initial large power draw and you can use minimal heat once you're ready to go.
JohnnyG
Weee!
hmm, well I'm basing my facts off of data from the manufacturers, but I guess they could be wrong and our beliefs could be more accurate
"The (2016) Leaf has 23.6 cubic feet of cargo space behind its rear seat. That number increases to 30 cubic feet with the standard 60/40-split rear seat folded."
"The 2016 Model S has 26.3 cubic feet of cargo room behind its rear seats and 58.1 cubic feet with them folded."
Note: this does not include the extra 5.3 cubic feet of the frunk (which wouldn't apply for this specific topic).
That works out to 1.94 times larger, or 94% larger.
Also noteworthy... Lets compare the 2012 Model S with the 2012 Leaf...
Model S: <all the same specs>
Leaf: 14.5 cubic feet behind rear seats. 24 cubic feet with rear seats folded down.
That works out to 2.42 times larger, or 142% larger.
I didn't know what year your Leaf was, so I wanted to be fair...
JohnnyG
Weee!
At this point in the conversation, I was simply referencing the section of the car with the most noticeable difference.
And here, you stuck with the point, but were incorrect with your guessing.
Now this is were I used actual facts instead of opinions to further the conversation.
Uh-oh, this is the part where you were called-out and now want to change the point of reference, and try to be witty by using quotes you see on the television.
hmm, it may be time to replace the batteries in your calculator (reference actual numbers above that support the original point that was being made), and refine your reasoning skills (30% is not almost exactly 40%).
Enough said..... I'm not going to continue arguing with someone who changes someone else's points of reference just to sound witty.
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