Winter Hit

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Hybrids are definitely ideal for warmer climes, but the hit so far in the Northeast has not been as bad as thought (first winter with the hybrid), although cold weather is just beginning. With temps now in low 40s or even high 30s in the morning, the car is in EV mode as normal at start, unless I turn on climate control. Without any heating, I have seen about a 1-2 mpg hit overall. The hit is mostly in the first 5 minutes and with acceleration. The vehicle is designed to get the batteries warmed up (again, without considering heating in the cabin, which takes a hit until the ICE warms up), so there is a hit even without heating. But it's not very bad overall. I can still get super high per-trip mileage, but the hills I have to climb within the first few minutes of my commute take a toll on the overall. We don't get much below freezing here in the winter, but it will get a bit colder. I am interested in seeing how it pans out. I am mostly driving without heat to get a baseline. With a coat on it's not too bad. The fogging up of the windows is the only thing, but a second of climate control on takes care of that (I'd prop the windows a bit, but it's already too brrrrr). Once I get sick of all this, I'll just drive it like a normal car with heating and take the winter hit. I'll still get better than I got with any other car. I just want to see what the mechanical side of it does in the winter without any heating. The heated seats don't hit the gas mileage at all, and that is about all I need most of the time anyway. I'll see what happens as it gets colder.

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Of course, all cars take a hit in cold weather, but it's more noticeable with a hybrid, since you are more focused on gas mileage and also since it's compounded by all the cold-weather inefficiencies ICE and EV adding up. Heated seats rock, though. You don't need the ICE to heat the cabin, since the electrically warmed seats keep you warm. But this will only last so long, and I'll be heating the cabin. I wonder, though, it may be counterproductive to not heat the cabin. The cabin heat warms the batteries, so that they start operating more efficiently. Maybe better to just warm and take the early hit. If you have a short commute, you are screwed with an ICE-only vehicle and doubly screwed with a hybrid, but even so you'll get better winter mileage with the hybrid. I just think the differential will be greater and more noticeable with the feedback with the hybrid. Thus, the conventional "wisdom" that hybrids are not for cold weather. No cars are, even if the difference is a bit more pronounced on the ground and perception-wise with a hybrid, but you're still doing better in absolute terms than with an ICE-only vehicle. Damn cold weather.

[Buster1]

I have not looked at the ACC meter with heat on, but it can't be that significant. The ICE is always producing heat. Sacrifice the juice it takes to turn on a little fan to bring in that heat, and I bet your overall MPG will look about the same.

[VonoreTn]

Here is full data for my '10 FFH, based on keeping every gas fill-up data for the first 23,000 miles. I saw a definite impact from cold weather.

 

 

The overall average right now is real close to 39 mpg.

Edited November 11, 2010 by VonoreTn

[EGFP]

Here is full data for my '10 FFH, based on keeping every gas fill-up data for the first 23,000 miles. I saw a definite impact from cold weather.

 

 

The overall average right now is real close to 39 mpg.

 

Thanks. Very interesting and nice benchmark. I'd say I am seeing the same performance, though I've had the car for a much shorter period.

 

One thing I've noticed is that turning on the cabin heat does show up in ACC as a noticeable blip, especially until the ICE is warmed up, and then it goes down. Also, until the ICE is warmed, with cabin heat on, even at a stop, the ICE is running. But if I turn off the cabin heat and just run the seat warmer, even at the first stop, the car idles in EV only. It all makes sense. Winter takes a bigger hit than just on ACC, though, obviously. Any ICE in winter doesn't run as fuel efficiently until it is warmed up, since the oil in the engine is colder and more viscous, so more gas to move the pistons. Also, with cooler denser air, there is more wind resistance. The air in the tires also is less expanded, so slightly inflating the tires may help. That's true of all cars. With a hybrid, there's also the decreased efficiency of battery under the rear seat when it's very cold.

[Oman]

Most people forget to add in the single biggest impact in cold weather states after cabin heat/emissions system heat - fuel blend. Winter blend in Minnesota has about 3% less energy then Summer. Comes right off the top.

 

Jon

 

 

Thanks. Very interesting and nice benchmark. I'd say I am seeing the same performance, though I've had the car for a much shorter period.

 

One thing I've noticed is that turning on the cabin heat does show up in ACC as a noticeable blip, especially until the ICE is warmed up, and then it goes down. Also, until the ICE is warmed, with cabin heat on, even at a stop, the ICE is running. But if I turn off the cabin heat and just run the seat warmer, even at the first stop, the car idles in EV only. It all makes sense. Winter takes a bigger hit than just on ACC, though, obviously. Any ICE in winter doesn't run as fuel efficiently until it is warmed up, since the oil in the engine is colder and more viscous, so more gas to move the pistons. Also, with cooler denser air, there is more wind resistance. The air in the tires also is less expanded, so slightly inflating the tires may help. That's true of all cars. With a hybrid, there's also the decreased efficiency of battery under the rear seat when it's very cold.

[JimFFH]

Most probably don't think about it, but I think the tire pressure is part of this equation as well, may bump it two pounds and check the mileage out. May reduce that winter hit.