We just had a few cold days ( -1 to 10 F) right when I filled it up and to my horrible suprise I got 25mpg those two days. Is this common when its so cold. normally I get 35 to 41 mpg.

 

Yeah, today it was pretty cold here and my tank ave is only 35mpg .

 

The weather has been cold in upstate NY (5 to 10F) and am still getting about 35mpg on average.

 

Make sure you check your tire pressure. As the temp gets colder your tires loose pressure and will help to cause a reduction in fuel economy. This isn't just limited to the hybrid cars though, the factors that make the hybrid less efficent are also in play for ICE cars...were the hybrid takes a big loss is the ICE is trying to maintain it's temp so it runs more. As you run your heater you cool the engine and then the engine needs to run more.

Colder air is more dense so it requires more power to push through
Colder temps make increases the drag in all the bearings in your cars system which will impact FE

 

Temperature was down to 54 degrees this morning here in SW Florida when we drove to breakfast, Still getting about 39 miles per gallon.

Bob

 

Tire pressure is important as noted previously, consider going to nitrogen in your tires. It doesn't contract as much in the cold.

Factors affecting your FE ( and everyone else's also, btw ) in decending order of importance...
1) Towing anything is a huge penalty possibly as much as a 50% reduction in FE
2) Lots of weight in the vehicle, passengers cargo etc. ( EPA tests are done empty )
3) Short trips under 10 min - deduct 20% from your 'Norm'
4) Snow, Rain, sleet - deduct 15%
5) Strong head wind - deduct 10%
6) Cold weather - deduct 5 - 10%
7) High speed driving 0ver 70 mph - deduct 5 - 10%
8) Many starts from a dead stop ( going from stop sign to stop sign to stop sign ) - deduct 5 - 10%
9) Terrain - fortunately 'what goes up..' usually this balances out on a RT
10) Winter fuel - deduct 2 - 5%

Now these are cumulative, so short trips with a lot of stops ( -20% )( -5% ) in winter ( -7% ) on slick pavement ( -15% ) can result in as much as a 40 - 50% loss from your personal 'Norm'. The bright side of this is that your 'Norm' is higher than most others at 39 mpg. If your Norm was only 26 mpg for example you might expect to get 13-15 mpg.

This is really really important when you consider how much more fuel you use in cold weather but also how much less you use relatively to a an ICE-only V6 driver. ( See below )

TCH 'Norm' @ 39 mpg uses 25.6 gal per 1000 mi driven
TCH 'Winter' @ 25 mpg uses 40 gal per 1000 mi driven

ICE 'Norm' @ 26 mpg uses 38.5 gal per 1000 mi driven
ICE 'Winter' @ 15 mpg uses 66.7 gal per 1000 mi driven

In 'Normal' driving an ICE driver will only use about 13 gal more than a TCH driver for every 1000 mi. In 'Winter' however, that ICE driver will now use over 28 gal more than a TCH driver for the same 1000 mi.

Enjoy your hybrid . It will be Spring soon.

 

Any thought to adding a radiator blanket like you see on cold weather trucks? Lower air flow through the engine compartment would keep the ICE warmer.

I've just realized the irony of the acronym: the ICE needs to stay warm.

 

If you are in an area that is required to use reformulated gasoline during winter your are really screwed.
Are "cold people" more dense too??

 

KDHSPYDER Thanks for the post. I think I fell victim to #3-6-8-10 I think the percent for cold may be worse than thought,we had -4f one of the nignts and it took some time for the batterys to help out.Factors affecting your FE ( and everyone else's also, btw ) in decending order of importance...
1) Towing anything is a huge penalty possibly as much as a 50% reduction in FE
2) Lots of weight in the vehicle, passengers cargo etc. ( EPA tests are done empty )
3) Short trips under 10 min - deduct 20% from your 'Norm'
4) Snow, Rain, sleet - deduct 15%
5) Strong head wind - deduct 10%
6) Cold weather - deduct 5 - 10%
7) High speed driving 0ver 70 mph - deduct 5 - 10%
8) Many starts from a dead stop ( going from stop sign to stop sign to stop sign ) - deduct 5 - 10%
9) Terrain - fortunately 'what goes up..' usually this balances out on a RT
10) Winter fuel - deduct 2 - 5%

 

kdhspyder — At normal temperatures, both air and nitrogen obey the universal gas law (PV = nRT) pretty accurately. The pressure of a fixed quanitity of gas is directly proportional to its absolute temperature (in kelvin = degrees Celsius + 273). Thus, the tire pressure will vary with temperature by exactly the same amount for both air and nitrogen.

Stan