Will Cybertruck use heat pump or resistance heater?

[stumby]

The Model Y is the first Tesla to feature a heat pump instead of the Model S and 3's resistance heater. The heat pump means better range in the cold and winter. Any reason to think that Cybertruck won't come with a heat pump?

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[drcarric2650]

Let's consider model Y as being a test vehicle, if it pan's out well, I'm sure the Cybertruck will have it as well.

 

[Replicanthunter]

Heat pump sounds better but likely more maintenance. Let's hope the truck is highly serviceable.

 

[Michael Mehta]

My 2017 Chevrolet Volt has a heat pump. It works exceptionally well and uses little energy. The car heats up and cools down very quickly. You'll also want heated seats and a heated steering wheel since it's easier to stay warm if your bum and hands are toasty. I use the Volt mostly in the interior of British Columbia, Canada, where temperature range can be -30C to +40C.

 

[drcarric2650]

My 2017 Chevrolet Volt has a heat pump. It works exceptionally well and uses little energy. The car heats up and cools down very quickly. You'll also want heated seats and a heated steering wheel since it's easier to stay warm if your bum and hands are toasty. I use the Volt mostly in the interior of British Columbia, Canada, where temperature range can be -30C to +40C.

And there is an added benefit of wanting to keep your hands on the wheels, when in auto drive.

 

[Deleted member 2423]

I think that it would be a great idea. My Honda Accord hybrid uses way more gas in cold weather just to keep me warm. I'm sure it would be similar in a pure EV.

 

[Bond007]

I believe all the future versions of model S, X and 3 (of course also including Cybertruck) with all use the heat pump. It’s such a great idea I wonder why Tesla didn’t implement it sooner.

 

[ajdelange]

The Model Y is the first Tesla to feature a heat pump instead of the Model S and 3's resistance heater. The heat pump means better range in the cold and winter. Any reason to think that Cybertruck won't come with a heat pump?

No, there isn't as all the current Tesla models have a heat pump of one sort or another even if it only be the air conditioner. Tesla in the last year or so filed a patent on a motor vehicle heat management system that like all good patents claims lots and reveals little but it seemed to cover almost every thing as it included compressors, heat exchangers, pumps, valves, radiators and, probably, electric heaters but to be honest I don't recall. A heat pump is a device which can move heat against a temperature gradient. In warm weather the sun streams into the cabin and warms it and hot outside air and waste heat raise the temperature to undesirably high levels unless the heat pump can take that heat and push it outside the car. In the winder the cabin and battery need to be warmed and waste heat from the motors, inverters and internal battery losses are insufficient. We must either use battery energy in a resistance heater or by setting the inverters to be less efficient in order to get the heat unless we can pump heat from outside into the vehicle. This can be done with an obvious improvement in range within limits by swapping evaporator and condenser in the A/C (that's what all the valves and pumps are for) so that it becomes what most people think of when the terms "heat pump" is used. But there are limits on the extent to which this can be done. From freezing (0 °C) we should, theoretically, be able to extract 13.65 kWh of heat at the cost of 1 kWh of battery. In fact the best systems might extract 3. At -20 °C we could theoretically be able to pull about 6 kWh heat from the air at a cost of 1 kWh of electricity but can, in the real world, pull very little and the heat pump becomes no more efficient than an electric heater.

I don't know what the actual heat load is for the cabin and battery of the CT but I know it isn't much in the region above freezing to the point that seat heaters are generally enough but whizzing across the prairie at - 20 °C is going to be a different matter. A compressor that consumes 1 kW will produce 3412 BTUI/h (1/4 ton) at -20 °C (these are representative numbers) and perhaps 3/4 ton at 0 °C. IOW it's great when you don't need it but not so useful when you really need it. Thus there will have to be an auxiliary heat source. Rumor has it that that source is the inverter transistors which sounds really clever but I don't know whether that rumor is true.

All in all I'm pretty sure there will be a heat pump that can extract heat from the outside air if it is warm enough.

 

[907Firefighter]

No, there isn't as all the current Tesla models have a heat pump of one sort or another even if it only be the air conditioner. Tesla in the last year or so filed a patent on a motor vehicle heat management system that like all good patents claims lots and reveals little but it seemed to cover almost every thing as it included compressors, heat exchangers, pumps, valves, radiators and, probably, electric heaters but to be honest I don't recall. A heat pump is a device which can move heat against a temperature gradient. In warm weather the sun streams into the cabin and warms it and hot outside air and waste heat raise the temperature to undesirably high levels unless the heat pump can take that heat and push it outside the car. In the winder the cabin and battery need to be warmed and waste heat from the motors, inverters and internal battery losses are insufficient. We must either use battery energy in a resistance heater or by setting the inverters to be less efficient in order to get the heat unless we can pump heat from outside into the vehicle. This can be done with an obvious improvement in range within limits by swapping evaporator and condenser in the A/C (that's what all the valves and pumps are for) so that it becomes what most people think of when the terms "heat pump" is used. But there are limits on the extent to which this can be done. From freezing (0 °C) we should, theoretically, be able to extract 13.65 kWh of heat at the cost of 1 kWh of battery. In fact the best systems might extract 3. At -20 °C we could theoretically be able to pull about 6 kWh heat from the air at a cost of 1 kWh of electricity but can, in the real world, pull very little and the heat pump becomes no more efficient than an electric heater.

I don't know what the actual heat load is for the cabin and battery of the CT but I know it isn't much in the region above freezing to the point that seat heaters are generally enough but whizzing across the prairie at - 20 °C is going to be a different matter. A compressor that consumes 1 kW will produce 3412 BTUI/h (1/4 ton) at -20 °C (these are representative numbers) and perhaps 3/4 ton at 0 °C. IOW it's great when you don't need it but not so useful when you really need it. Thus there will have to be an auxiliary heat source. Rumor has it that that source is the inverter transistors which sounds really clever but I don't know whether that rumor is true.

All in all I'm pretty sure there will be a heat pump that can extract heat from the outside air if it is warm enough.

Thinking you need to look up on how the heat pump actually works...
The Y is the first Tesla with it.

 

[ajdelange]

A heat pump is a device that pumps heat against a temperature gradient. An air conditioner is a heat pump! The only difference between what the layman calls a "heat pump" and what he calls an "air conditioner" is a reversing valve which allows the refrigerant to flow compressor exhaust --> heat exchanger A --> metering device --> heat exchanger B --> compressor suction OR compressor exhaust --> heat exchanger B --> metering device --> heat exchanger A --> compressor suction.

Your mistake is a common one. Teslarati posted an article announcing that a Y owner had discovered the "heat pump" which article contained this frame from the guy's video.

Obviously he thinks the thing he has circled is the "heat pump". It is actually the compressor which is, of course part of the heat pump system but my X has one of those too (also located behind the frunk tub) and so do the S and 3. If you follow the two tubes/hoses from the top of the compressor to the left you will see them attach to another component to the left of the square box with the yellow tape. That is (I assume) the reversing valve which is what distinguishes the model Y heat pump from the ones in the other models (they don't have it0. Because of it the Y can not only pump heat from the interior of the car to the outside but can also pump heat from the exterior of the car into it.


What distinguishes the heat pump in my X from the heat pump in the Y is that the latter is the first application by Tesla of a reversible heat pump. Thus the person discovering the heat pump should have circled the reversing valve.

So I am thinking that it is you who should have looked up how a heat pump works (Wikipedia would have straightened you out in the first couple of paragaphs). Had you done so, of course, you would have deprived me of the opportunity to post the picture.

 

[Administrator]

Here's a good look at the Model Y heat pump (vs Model 3 eAC Compressor) by Sandy Munro.

 

[ajdelange]

He kind of stumbles and bumbles a bit. The thing he calls a compressor at the right end of the cylinder is the motor/inverter. You can see the battery wires going into it. He says that the left part of the cylinder is the "body of the heat pump'. It isn't. That's actually the compressor. The compressor takes low pressure gas from the large (suction or suction) tube and compresses it to much smaller volume and consequently much higher temperature which it pushes into the exhaust (high side) tube which is the smaller diameter one. The two tubes then go to a valve assembly which directs the hot gas to someplace to which heat is to be delivered. The hot gas condenses to liquid there and the valves/plumbing send that liquid to wherever it is the heat is supposed to come from where it boils and the gas from there gets sent back to the suction port of the compressor through the large tube which he does say later on. , sends liquid from that place to another from whence this heat is supposed to come At least that's the way it is on every system I've ever seen but that's really not that many. The only thing that strikes me as being strange here is that the thing with the yellow cap is a service port and right at the compressor output strikes me as kind of a wierd place to put it. Where's the low side service port?

Just another observation: the battery looks bigger than the little motorcycle batteries in the other Tesla cars.

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