R2 / R3 has heat pump (confirmed by RJ)

[jbssfelix]

The BEV Heat Pump hype is real, but science and engineering paints a bleaker picture. Those who have heat pumps at home know that they get less efficient as the OAT (Outside Air Temperature) drops, and that an auxillary heating source may be needed below about 25F/-3c. If your OAT is 40-70F you will save energy in your EV with a heat pump. But if you are routinely 32/0c or below, the benefit of a heat pump vs. PTC is minimal, and gets worse as the temperature drops and becomes break even. You won't see any benefits in cold weather, and it WILL take longer for the cabin to warm up - if it warms toasty up at all, as @jbssfelix mentioned above.

"For highway driving in cold conditions, the share of losses is dominated by battery and aerodynamic effects, and cabin losses account for 5-10%. With a system COP of 1.5 and losses of 5-10%, the benefit of a heat pump for cabin conditioning would be on the order of 1.7 -3.3%. Then the mass of the heat pump system slightly reduces the overall impact of a heat pump.

Although heat pump systems on average save energy and increase range, it is not surprising that customers don’t notice the small heat pump benefit in cold highway driving. Coolant waste heat recovery and multiple-source heat pumps may provide greater range improvement than air-source heat pumps in cold conditions."

Heat pumps are getting much more efficient (I think I read/saw somewhere of residential heat pumps being produced that work down to -10F...but still very very new), and the Tesla one works just fine in the teens and above. But as you mentioned, the colder the climate, the less likely a heat pump is going to be effective during those coldest of days.

Heat pumps are awesome, and I am a fan, as they are wildly efficient when operating in their normal range. But if you live in a place that gets proper winters, it's definitely something you'll want to do research on first.

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[usofrob]

I remember seeing this video last year during the cold snap. They compare a resistive heater model 3 to a newer one with a heat pump

Edit: also I see in the comments the ptc heater used about 8kwh while the heat pump car used 5-6. Another takeaway is Kyle thinks the heater and insulation in his Rivian is better than his Teslas

I was going to point to this video as well. The heat pump warmed up the vehicle a lot quicker than the PTC heater (in this test). So, it would seem dependent of the design of the heat pump before one can say a heat pump won't warm things up as quickly. This result surprised them as well.

 

[KootenayEV]

I was going to point to this video as well. The heat pump warmed up the vehicle a lot quicker than the PTC heater (in this test). So, it would seem dependent of the design of the heat pump before one can say a heat pump won't warm things up as quickly. This result surprised them as well.

Poor test design, I don't think you can believe the purported results. Take a look in the comments section and see what I mean.

 

[Dave Cundiff]

Both of our EVs have a heat pump, so I don't have any experience with resistive heat in EVs. What's the efficiency hit with the R1 platform when using the current method of heating?

Significant.

We engage heated steering wheel and heated seats before using resistive heating.

A clear windshield is non-negotiable though. We spend as many electrons as we need to be safe.

 

[Zoidz]

I was going to point to this video as well. The heat pump warmed up the vehicle a lot quicker than the PTC heater (in this test). So, it would seem dependent of the design of the heat pump before one can say a heat pump won't warm things up as quickly. This result surprised them as well.

This video is not a conclusive test that the design of the heat pump made the vehicle warm up more quickly - it shows the heat pump SYSTEM warmed he vehicle up more quickly. In extremely cold temperatures, the heat pump equipped Tesla is using supplemental resistive heating by heating up the motors and other components using battery power.

This is well documented in this YouTube Video. The Heat pump equipped Tesla has 30 modes of operation and sixteen (yes 16) sources of heat, including running things inefficiently such as heating up the inverters, various motors, etc. At this low temperature, they are using other additional sources of heat in addition to the air exchange heat pump. Just like there is no such thing as perpetual motion, there are rules of thermodynamics that you can't magically defeat, despite that Elon might want you to think it's solely some new air exchange heat pump magic. There's power being consumed behind the scenes to create heat from resistive heat sources.

This video is pretty technical, especially when he talks about the various refrigeration cycles. But at 38 minutes he sumarizes the heat sources in a Telsa. He states that these other heat sources have an energy cost just as high as a PTC heater.

 

[usofrob]

This video is not a conclusive test that the design of the heat pump made the vehicle warm up more quickly - it shows the heat pump SYSTEM warmed he vehicle up more quickly. In extremely cold temperatures, the heat pump equipped Tesla is using supplemental resistive heating by heating up the motors and other components using battery power.

This is well documented in this YouTube Video. The Heat pump equipped Tesla has 30 modes of operation and sixteen (yes 16) sources of heat, including running things inefficiently such as heating up the inverters, various motors, etc. At this low temperature, they are using other additional sources of heat in addition to the air exchange heat pump. Just like there is no such thing as perpetual motion, there are rules of thermodynamics that you can't magically defeat, despite that Elon might want you to think it's solely some new air exchange heat pump magic. There's power being consumed behind the scenes to create heat from resistive heat sources.

This video is pretty technical, especially when he talks about the various refrigeration cycles. But at 38 minutes he sumarizes the heat sources in a Telsa. He states that these other heat sources have an energy cost just as high as a PTC heater.

That makes sense. Thanks for sharing.

I was just kind of assuming the heat pump would just generate heat by trying to run and just run really inefficiently. But, using other sources of heat makes more sense.

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