Pre-heat feature

i'm not sure we can answer those questions. it may depend on how frosty the windshield is, but maybe someone with heat pump technology knowledge might know how long it takes to produce heat, and that might depend on ambient temperature and humidity.

 

If it works like the 2013+ Leaf with heatpump, the heat is instant and all electric which will be like the Prime when plugged in. If by defrost you mean when it is a little cold outside and windshield fogs up yes 10 minutes of pre-heat should clear it. However if you mean it is -30C outside with 10cm of snow and ice on the windshield, it won't clear it. On those days, I pre-heat for about an hour with the Leaf which is enough to make the ice lose the death grip from the windshield so I can brush it off easily versus standing there scraping it. And after an hour, the entire cabin has heat soaked so everything is warm and you don't even need HVAC for the next half hour or so.

 

The heat pump is an air-conditioner. It will produce hot air in the same time it typically takes an air conditioner to produce cold air in the summer. What's that, about 5-10 seconds?

If the defroster (air against the windshield) is worth anything, it should loosen ice, even thick ice, in 10 minutes. That's because it only has to melt the first molecule (literally) of ice touching the windshield to allow you to push it off. My experience with all my cars including my 2004 Prius backs this up.

However, if it's below -10C or 14F, the heat pump won't do the job and the ICE will have to run to assist in heating the car. If the engine is cold soaked it could take a while to warm up (5-10 minutes or longer at idle if it's that cold).

 

Ugh. Living in Minnesota since for the past 39 years, I'm well aware of winter driving extremes. The odds of it being both -22°F outside and getting 4" of snow at the same time is pretty much never. Snow flakes don't form when it's that cold. You get a light coating of thin ice crystals, at best.

A far more realistic example... which I will experience firsthand in 3 months... is the Prius sitting outside all day with the high temperature of -1°F. That happens every year. Warm-up takes about 10 minutes with the engine starting up right away. Defrost usually isn't needed, since I vent prior to stopping. It's just get in, make sure the seat-heater is on high, then drive away.

With the Prime, windows will certainly be clear already. In addition to the heated seat, the steering wheel will provide warmth too. Driving away will be comfortable. Heck, even the battery-pack will feel the improvement. Those extreme cold days will take a bizarre twist. What a great feature to draw interest.

As for dealing with 4 inches, no one would ever run there vehicle long enough to attempt to melt off such a thick amount. Even my idiot neighbor who would idle her diesel for 45 minutes before leaving for work would brush the windows off quick with that much snow. Of course, there are those who just sweep a tiny viewing hole and drive away with a drift on the car still. But that's only when the temperature is much warmer. Between 20°F and 32°F is when we get the really heavy dumps.

Long story short, the new vapor-injected heat-pump has much to offer.

 

The air conditioner is moving an excess of heat out of space. A heat pump is concentrating a shortage of heat into a space.
So it might not be air conditioner making cold blowing fast when it is really cold out, but it will be much faster than having to heat up the ICE and coolant.

 

Once it's 72 degrees inside the car, and 100 degrees outside the car, it still works. It does this because it can pump heat in the "wrong direction" - the opposite direction to its natural direction of flow.

An air conditioner pumps heat from the cool pool in the car to the hot pool outside the car.

A heat pump pumps heat from the cool pool outside the car to the hot pool inside the car.

The same device is used for both purposes and it thus works in the exact same way. The "gas injection" just makes it a little more efficient when the cool pool is really cold and there ends up being a very large temperature difference.

 

Yes, they use the same process to move heat.
A heat pump doesn't make heat to warm up a space, it gathers it from outside. Cold isn't a thing, it is the absence of heat. Like darkness is the absence of light.
When it is really cold out, there is little heat for the heat pump to gather up to move into the car, and it takes for more effort(energy, time) for the heat pump to heat up the cabin. Too cold outside, and the heat pump is simply unable to move that little amount of heat in a manner that will warm the cabin.
When cooling a space, the air conditioner doesn't have to deal with there not being enough heat to gather up. There is plenty, or the person wouldn't be hot.

 

This is only true once the cabin is warm. It's hard to pump heat from cold to hot, not from cold to cold. If the outside is 20 and the inside is 20, not much effort is involved.

 

Except that there is less heat available for moving than when it is 40 inside and out.

It takes less energy to move heat around than to make it, but there needs to be heat laying around in the environment for a heat pump to move it. A geothermal heat pump is more efficient than an air source one because there is more heat underground than in the air for heating during winter.

 

There may be some misunderstanding here. The heat energy available is linear with the absolute temperature. For example, in Celsius there is not much difference in available heat between -20 and +10, namely 273-20= 253 versus 273+10= 284, which only differs by a factor 1.12, which is 12%. So, there is always enough heat available. The only thing is that the effort needed by the heat pump goes up with the difference in temperature between inside and outside.

 

I was sloppy in my writing. As long as sub atomic particles are in motion, there is heat in the system. But heat pumps don't work down to 1 degree Kelvin. The limitation that a heat has is because of a heat differential. The one between the expansion coil and the outside air. The differential between the condenser and the space your heating doesn't become a factor until you are trying to make a sauna.

When the refrigerant expands in the coil, it needs heat for that expansion, and sucks it from the surrounding environment. The factor in how much heat it takes up during its passing through the coil is the difference between how cold it makes the coil and how much heat is available outside. The larger the difference, the faster the ambient heat transfer to the coil and then the refrigerant. The smaller, the less heat that transfers, the more effort for the heat pump to heat up the space. That is what I was referring to in my sloppier posts

When the refrigerant enters the expansion coil, it contains a level of heat already. The minimum level of outside temperature a heat pump can work at is because the heat differential is at the point where the refrigerant isn't cold enough after using up that internal heat to drive the transfer of external heat in.

The refrigerant contains heat because we are no where near absolute zero, and inefficiencies in the device. That main inefficiency is the fact that the refrigerant needs to be compressed before going into the expansion coil. As it passes through the condenser coil, it sheds the heat it picked up from outside. It becomes less energetic as it does so, and starts to condense back down to its fluid state, but it doesn't reach the the right pressure for the system to work by this alone. This were the compressor cans in.

It, well, compresses the refrigerant so that it is under high pressure, and then the refrigerant gets squirted into the lower pressure expansion coil to repeat the cycle. But when things are compressed, they heat up. So a typical heat pump is heating the refrigerant right before we need it at its coldest. What a gas or vapor injected heat pump, like the Prime has, does is take a bit of the compressed refrigerant, and squirts it onto the compressor blades. Cooling the compressor thus reduces the amount of heat generated during compression.

 

http://www.toyota.com/content/interior-tours/priusprime/images/features/full/PRP_MY17_0041_V001.jpg?interpolation=lanczos-none&output-quality=90&downsize=1228px:*?interpolation=lanczos-none

Remote Climate

Take control and use your smartphone with the available Prime apps 8 including the Remote Climate app. 7 This way, you can check your Prime’s current temperature setting and change it to your liking—all before you even get in. When Prime is plugged in, the power used for Remote Climate is pulled straight from the grid so your battery keeps its charge. Now your comfort is always within reach.

Note the defrost switches and the red "heat" range under the thumb.

 

Remote Climate is available only on the Advanced AFAIK.

Posted via the PriusChat mobile app.

 

Via smartphone, yes, but I think the others have it via key fob remote.

 

fob probably only starts the a/c at whatever setting you leave it on, like the pip. and then, only within fob distance.

 

Correct.

"The Remote Air Conditioning System will operate in accordance with the temperature settings of the air conditioning system."

"Press and hold “A/C” on the wireless remote control to operate the Remote Air Conditioning System. The system will shut off if a door is
opened. The system can be stopped by pressing “A/C” twice."