Snow storm

[Tha_Ape]

That's false. Heat pumps designed to heat in freezing temperatures do exactly that. The mini-split I installed in my ski cabin is rated at 100% of its BTU rating at 5 degrees Fahrenheit and it has no resistive heating elements in it. At a very frigid -10 degrees F it will be well under its BTU rating but will still provide heat. Of course, it never gets -10 degrees there, I'm just saying it would still work. My cabin just went through two weeks of temperatures in the single digits and the teens and the only thing keeping the plumbing in the 1200 sq. ft. cabin from freezing was a single one-ton mini-split. Worked great and cheap to operate.

You need a heat pump designed for cold climates. The resistive element is a band-aid, the ones that work well in cold climates run higher pressures, different refrigerants and more efficient heat exchangers and fans. Even the valves are designed to maximize cold weather efficiency.

Heat pumps need to extract energy from the cold air (which there is very little of). Are you saying the Tesla's heat pump is designed for freezing temps?

 

[Lloyd]

The average gas car can idle for 32 hours. A model s with heater can stay warm for 36 hours at 30 degrees. The electric can plug in anywhere where the gas car has to find a gas station!

 

[Jjrss]

Heat pumps need to extract energy from the cold air (which there is very little of). Are you saying the Tesla's heat pump is designed for freezing temps?

Heat pumps are magic wizards depending on the refrigerant used. There is a ton of energy, IE heat, available for the heat pump to exploit at 0 degrees. The Tesla is designed with a few feed back systems to reclaim the heat expended in other subsystems as well. Hence that Octovalve setup.

Tesla Model Y Heat Pump Details Infrequently Discussed By The Media

Tesla’s new system “boosts” the heat pump to give it better efficiency than regular heat pump systems and uses unique methods for heating below -10C.

insideevs.com

 

[MG535]

These British YouTubers drove their EVs until they died. They called the RAC (like AAA in the USA) which came in a specially equipped van to provide enough juice to make it to a charging station.

At around 42 minutes

Now if your luck is really bad you’ll get just enough juice to make it to a charger to find that it doesn’t work (just like ICEV found empty gas stations off I95 in VA) or that the line is X cars deep.

 

[Xdama]

~7kWh is about $12k and almost 300 pounds. AAA actually had a rescue vehicle for EVs a few years ago but due to lack of use I think they’ve actually discontinued it. Ideally if Tesla started to deploy roadside assistance vans to their mobile service hubs with a couple powerwalls in them they probably could pack 20kWh or so into it and use that as a rescue… but I suspect that would even see a short life. As superchargers show up more and more it’s probably faster, cheaper, and easier to just get a flatbed tow to one. HOWEVER, in a natural disaster or winter storm you might have a huge backup with towing services in which case 10kWh pumped into the vehicle might be a huge benefit compared to waiting for a tow.

Maybe we’ll see F150 lightning owners make a few extra bucks acting as recovery vehicles. Not sure the amps on the 240v, but it may be able to do 7.2kW. The Rivian might also be able to do it after some OTA updates down the road…

In UK the main recovery services have trucks with generators on now for EV battery charging. I think they give you enough range to get to the next EV charger (not supercharger).

 

[Itsuo-DC]

Byron did a 'How long can a Tesla keep you warm in winter?' test about a year ago. Definitely worth the time to watch. It should put to rest anyone's concerns.

This was SO good. I watch Bjorn regularly but missed this video. One thing mentioned, but maybe lost on viewers, is that insulating the glass and especially the windscreen could be much more efficient as the M3P he used worked extra to keep the front windscreen clear of any build up. So if you have a sun/windscreen cover, or anything you can put in the windows/windshield to help insulate you could greatly extend your trip.

I also wonder if many drivers (but Tesla/EV users more specifically) would be more likely to be using GPS/traffic monitoring that may discourage them from using the interstate vs others who may have just been following a general direction.

 

[CyberGus]

A winter test by Dirty Tesla.

 

[CyberGus]

Looks like there's been another pile-up, this time in Kentucky:

Winter storm leads to pileup involving up to 75 vehicles on Interstate 64 in Kentucky​

https://www.nbcnews.com/news/us-new...-75-vehicles-interstate-64-kentucky-rcna11326

"In a tweet, Kentucky State Police also said I-64 was closed at mile marker 179 “due to a tractor trailer jack knifed.” Several other highways in the area “are solid ICE," state troopers said in another tweet."

Well there you have it..."solid ICE", no Teslas involved

 

[avs007]

I also wonder if many drivers (but Tesla/EV users more specifically) would be more likely to be using GPS/traffic monitoring that may discourage them from using the interstate vs others who may have just been following a general direction.

In winter weather conditions, I tend to ignore my GPS, and stick to major routes. The last thing I need is for the navi to take me down a forest road and get stuck somewhere. A few years ago, I was driving to the coast, and I was following the navi, becuase I thought it was having me take a state highway, because the general directions looked right... It actually ended up taking me thru a dirt road over the coast range, while it was raining... Some of the potholes/puddles were the size of semi-truck tires. The wife freaked out, because it was the previous year that the CNET guy tried to do the same thing and died. Wife really freaked out when we got to a fork, and I had no idea which way to go.. Would've turned around, but we were more than halfway thru the dirt road, lol. Luckily we made it. That was the last time I just blindly followed GPS.

 

[WW_VA]

Theres always the risk of the lithium ion funeral spire.

Pyre, not spire, but hey, it's your funeral

 

[Jjrss]

Pyre, not spire, but hey, it's your funeral

I've gotten so many thumbs down... people need to lighten up...

 

[Tha_Ape]

I've gotten so many thumbs down... people need to lighten up...

Looks like you lit a fire under them

 

[Itsuo-DC]

In winter weather conditions, I tend to ignore my GPS, and stick to major routes. The last thing I need is for the navi to take me down a forest road and get stuck somewhere. A few years ago, I was driving to the coast, and I was following the navi, becuase I thought it was having me take a state highway, because the general directions looked right... It actually ended up taking me thru a dirt road over the coast range, while it was raining... Some of the potholes/puddles were the size of semi-truck tires. The wife freaked out, because it was the previous year that the CNET guy tried to do the same thing and died. Wife really freaked out when we got to a fork, and I had no idea which way to go.. Would've turned around, but we were more than halfway thru the dirt road, lol. Luckily we made it. That was the last time I just blindly followed GPS.

There is definitely a balance between blindly following and accepting better suggestions. I like your story but it also reveals the difficulty of evaluating the value of traffic related rerouting. I’ve tended to just trust it commuting or for longer trips. I’ll admit that sometimes I can absolutely tell it‘s going to save me from having to sit in bumper-to-bumper at the very least. Other times, it’s not so clear why the hell I’m way out of the way on some local road, etc.

A winter test by Dirty Tesla.

This is also great! Thank you for sharing. DT even quotes the article posted earlier from the WP!

Back to the snow storm; in speaking with others about the recent event in VA, I heard many people were routed onto other roads that were also not well maintained and they were stuck there as well. I also heard news reports that even when the event was ”relieved” there were huge lines at nearby gas stations and there were reports of at least one emptying out!

I don't understand your point. In five minutes you can provide fuel for many hours of idle or many miles of driving to an ICE vehicle. That's not possible in the near term for a BEV unless it supports rapid battery swapping and you have a national supply of such batteries that fit in a snowmobile trailer. So it's a BEV problem right now.

There is no dispute about the speed at which a ICE vehicle could be refueled; but, as others have mentioned, it would be possible to obtain additional range from regeneration via another vehicle pull-towing. It would be an inefficient one-to-one ratio but wouldn’t require a tow-truck. It also could be done without having to have an aux gas can, and potentially a fueling station nearby, etc. Not a panacea but also not as disasterous as all EVs needing individual tow-truck journeys to the nearest fast charger.

 

[jboy210]

@jboy210 as you probably already know in CA "true up" happens once a year. Even if you consume more than you produce in winter, as long as you make up for it in the summer you are still not buying power from your power company. And generally it is better to consume the power you overproduce than sell it to your power company (especially if you are buying power from PG&E). Combined with relatively mild weather in most of CA, heat pump instead of a natural gas furnace makes a lot of sense with an appropriately sized solar install.

I would not consume my over-production in the summer. Our solar roof fills the Powerwalls by 9-10 AM in late spring and early summer. I already charge the car and pre-cool the house with the excess, and still have significant additional excess solar power generation. The bottom line is a run out of places to store solar-produced electricity and only then sell it back to the grid. And this is in the East Bay where the summer temps are over 100 most of the summer.

And this comment does not address the issue of where electricity that powers a heat pump comes from. It is not being produced from hydro in the winter, especially in the last few years of drought. That means PG&E burns the natgas to create electricity and would ship it to me so I can use the electricity in a heat pump to heat. And there is an energy loss at each transformation and transmission. While I have not run the numbers, it seems more straightforward for me to burn it in my high-efficiency furnace, where I can control my consumption of natgas.

 

[Jjrss]

I would not consume my over-production in the summer. Our solar roof fills the Powerwalls by 9-10 AM in late spring and early summer. I already charge the car and pre-cool the house with the excess, and still have significant additional excess solar power generation. The bottom line is a run out of places to store solar-produced electricity and only then sell it back to the grid. And this is in the East Bay where the summer temps are over 100 most of the summer.

And this comment does not address the issue of where electricity that powers a heat pump comes from. It is not being produced from hydro in the winter, especially in the last few years of drought. That means PG&E burns the natgas to create electricity and would ship it to me so I can use the electricity in a heat pump to heat. And there is an energy loss at each transformation and transmission. While I have not run the numbers, it seems more straightforward for me to burn it in my high-efficiency furnace, where I can control my consumption of natgas.

While you can control your consumption of natural gas, it could be argued that your expenditure of it to heat your home is multitudes less efficient than a large natural gas energy station is at generating the electricity you'd use to power a heat pump that is 300% efficient vs a 90~98% high efficiency furnace. For 1 unit of energy, a heatpump transfers 3 units of heat, either into your home or out if it (AC). For 1 unit of Natural Gas, your furnace transfers .9 to .98 of it into your home, the rest is lost in the exhaust.

Keep in mind, if you are "pre-cooling" I would assume that means you have an AC unit? The most efficient solution is having the cooling coil integrated into your HVAC and above or below your furnace unit. With today's tech, a heatpump would use a similar (or the very some) coil. I've got my LP unit stacked ontop the heatpump coil in my garage and I can set the temperature via my Nest thermostat for when to use either, depending on which energy source I want to utilize.

Also keep in mind, a heatpump is literally an AC unit with an additional valve. It has the exact same efficiencies of an AC unit, with the added benefit of being able to maintain a set temperature if the exterior temp dropped at night. It is much more efficient to "maintain" a temperature throughout a 24 hour cycle vs pre-cooling at the coolest time of day.

If you have an AC unit, there is really no reason to not have a heatpump, even if you only use heating mode as an emergency backup to your Natural Gas unit.

 

[ItsNotAboutTheMoney]

Heat pumps need to extract energy from the cold air (which there is very little of). Are you saying the Tesla's heat pump is designed for freezing temps?

Yes. Check out Bjorn Nyland's cold weather videos.
E.g. Model 3 with heat pump:

Results from camping with internal temperature at 21°C (69.8°F):
0°C: 0.9 kW (32°F)
-8°C: 1.3 kW (17.6°F)
-11°C: 1.1 kW (13.2°F)
-25°C: 1.95 kW (-13°F)

Note that the Virginia storm had temperatures dropping to the teens.

Driving, my Kona's PTC will draw much more than that.

The Toyota Prime heat pumps run down to 15*F.
The Nissan Leaf's hybrid heater only helps down to freezing.
.

 

[Tha_Ape]

Yes. Check out Bjorn Nyland's cold weather videos.
E.g. Model 3 with heat pump:

As a counterpoint:

https://www.reddit.com/r/TeslaLounge/comments/rzwd95

(just saw it posted today)

 

[StealthP3D]

Heat pumps need to extract energy from the cold air (which there is very little of). Are you saying the Tesla's heat pump is designed for freezing temps?

Yes, the Tesla heat pump is designed for cold temperatures. That's why it has a dual stage system (to perform well in sub-zero conditions). The recent problems experienced at -30 F up in Canada were mostly due to the louvers on the front grill being frozen open allowing that -30 F air to blast the system.

 

[jboy210]

While you can control your consumption of natural gas, it could be argued that your expenditure of it to heat your home is multitudes less efficient than a large natural gas energy station is at generating the electricity you'd use to power a heat pump that is 300% efficient vs a 90~98% high efficiency furnace. For 1 unit of energy, a heatpump transfers 3 units of heat, either into your home or out if it (AC). For 1 unit of Natural Gas, your furnace transfers .9 to .98 of it into your home, the rest is lost in the exhaust.

Keep in mind, if you are "pre-cooling" I would assume that means you have an AC unit? The most efficient solution is having the cooling coil integrated into your HVAC and above or below your furnace unit. With today's tech, a heatpump would use a similar (or the very some) coil. I've got my LP unit stacked ontop the heatpump coil in my garage and I can set the temperature via my Nest thermostat for when to use either, depending on which energy source I want to utilize.

Also keep in mind, a heatpump is literally an AC unit with an additional valve. It has the exact same efficiencies of an AC unit, with the added benefit of being able to maintain a set temperature if the exterior temp dropped at night. It is much more efficient to "maintain" a temperature throughout a 24 hour cycle vs pre-cooling at the coolest time of day.

If you have an AC unit, there is really no reason to not have a heatpump, even if you only use heating mode as an emergency backup to your Natural Gas unit.

Thanks. We already have a relatively new (5 years old) high-efficiency heater that has multiple stage outputs. But if we need to replace this in the future I will consider a heat pump.

I hope they blow warm air these days. My previous homes that had heat pumps blew air that was about the same temperature as the setting, and I did not like this.

 

[CyberGus]

The recent problems experienced at -30 F up in Canada were mostly due to the louvers on the front grill being frozen open allowing that -30 F air to blast the system.

You need to install the self-heating Starlink dish.

Or, get a bunch of cats. (NOTE: Starlink only supports Cat5)