I think what @SalisburySam is eluding to is that 325 miles of range does not net you 325 miles of range due to weather conditions, road conditions, internal air conditioning, etc.So how many > 300 mile trips do you take per year?
Probably no more than 4.
No. I'm a little surprised at that too. I always believed that a heat pump didn't require much more hardware than an air conditioner, and therefore would be a preferred choice for heating an EV. But there are probably reasons that I don't understand that make it too difficult to implement - plus, you'd still need a resistive heater when temps get too low for a heatpump, so maybe that's why it wasn't worth developing for Tesla.no word on adding a heat pump to better handle the cold temps and not affect range as significantly?
@Ingineer provides a tour of the Model 3's cooling system in this video. He also shows the cabin AC system starting at about 4:20.The heat exchanger that cools the coolant would then also have to heat it and may need to be replaced.
and already in the works...@Ingineer provides a tour of the Model 3's cooling system in this video. He also shows the cabin AC system starting at about 4:20.
Given the incredible engineering that went into the main cooling system (which can also heat), Tesla should have all of the expertise needed to design an appropriate heat pump. They probably just had better things for that team to work on (like battery/inverter/motor/computer cooling/heating for Model Y/pickup/semi/roadster etc.).
Tesla US Patent Application 20190070924 said:...In order to overcome the above-described shortcomings, among other shortcomings, a first embodiment of the present disclosure is directed towards a vehicle thermal management system that includes a vehicle heat pump system, a battery system coolant loop, a drive train coolant loop, a coolant circulation system, and control electronics. The vehicle heat pump system includes a compressor, a cabin condenser, a cabin evaporator, a cabin blower, and a chiller. The battery system coolant loop is in thermal communication with a battery system. The drive train coolant loop is in thermal communication with at least one drive train component. The coolant circulation system is configured to selectively cause the battery system coolant loop and the drive train coolant loop to be in thermal communication with the chiller. The control electronics are configured to, based upon at least an ambient temperature, a cabin temperature and a battery system temperature, control the coolant circulation system, and control at least one of the compressor or the cabin blower to operate in one of an efficient mode and a lossy mode, wherein in the lossy mode the compressor generates a greater amount of heat than when in the efficient mode.
I predict the following timeline for Model S/X design refresh:
Around 25 Jun 2019, Model S/X production will switch to the refreshed design
Around 18 Jul 2019, Tesla will announce that they have made the switch
Other details and commentary:
- New Model S/X will support Supercharger V3
- New Model S/X will have Track Mode
- Model S/X design refresh will include Model 3 style center console + touchscreen + air vents
- The new horizontal touchscreen in Model S/X will be dead center between the front seats just like Model 3. This has the following advantages:
• Passengers can watch movies too
• When driverless FSD is supported, passengers can see navigation, time left to destination, music playlist etc on the screen
• There won't be any need to create a vertical version of the firmware just for the low volume Model S/X. After the Model Y, Model S/X sales will drop to below 10% of Tesla sales.
• There is no need to create a different version for right-hand-drive cars when the screen is exactly in the center
- To reduce complains about S/X screen switching from vertical to horizontal, they might mention that the horizontal screen will be better to watch movies on when they add video playback support and free Wi-Fi at Superchargers
- The new S/X battery will use 2170 cells
- The battery capacity will remain at 100 kWh
- There will be a minor range increase because of weight reduction. S100D range could increase from 335 mi to 350 mi
- I think there is now an urgency to make the switch sooner rather than later because Model S/X not supporting Supercharger V3 is like a slap in the face to new S/X buyers.
- I'm 80% sure of the timing. This is related to Tesla's quarterly production calendar. In the last few days of June, they will start making EU cars that will be delivered in Sep. Therefore if the switch is to happen in Q3, production must switch in the last few days of June. I don't know the exact date. Therefore I wrote around 25 June 2019. It could be 24 June or 26 June but I think it will be the last few days of June because as soon as it's too late to deliver cars in the US at the end of each quarter, production switches from US to EU. Similarly, the announcement could happen on 17 July or 19 July. I don't know the exact date. 18 July is a best-guess. By the way, check out my other prediction here about Autopilot which turned out to be OK.
I finally got around to reading that patent.
Well.... sure, that's one way to think about it.1) normal cars use waste heat to heat the cabin. Not new. Doing it with an electric car is new.
The patent specifically mentions using an inverter.2) They could be using an inverter for the fans now but more likely PWM like other cars use.