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Increase in Wh/mile in heavy rain

Increase in Wh/mile in heavy rain

I know it seems illogical but the last couple of days during heavy rain and going through large puddles, my Wh/mile has increased from my avg. 320 to about 400 Wh/mile. Just wondering if anybody else have similar experience?

MassX1317 | 1 mars 2014

When there is rain there is wind as well. Both create more resistance and it will take more energy to power the car.

Peter1087 | 1 mars 2014

Make sense. In fact I just did a drive from San Jose to Colfax (about 190 miles) in my ICE for the first time in (forever) due to the bad weather and even in the ICE driving in the downpours I noticed that I went from 20.2 mpg to 18.6 on the trip. I would normally take my MS but due to the horrible weather I decided to take the SUV.

BTW: Glad I did - 4:30am as I was driving northbound on hwy 680, all 4 lanes were closed and all traffic diverted off the road through the mud, over a curb. Even though the MS would have been ok, glad I didn't need to subject my 21" tires/rims to that mess.

George with SacEV | 1 mars 2014

Yup, I saw much higher than usual drain on my drive coming back from Oregon in heavy rain all the way.

Captain_Zap | 1 mars 2014

My Wh/mi is the highest in a cold rain, plowing through water into a headwind. On some types of pavement I can run over 400 average, on other surfaces around 380. It seems like asphalt is much worse than concrete. It is probably due to depressions in the asphalt.

Jamon | 1 mars 2014

Posters here have also commented that the increased density of air in the rain/fog is enough to noticeably increase energy usage.

Bighorn | 1 mars 2014

Effective of water on rolling resistance...

http://www.nokiantyres.com/rolling_resistance

sweetmanpe | 1 mars 2014

Today driving in varying conditions saw 380 at 60 in the rain vs 300 at 70 on dry with similar flat terrain.

Koz | 1 mars 2014

Yes, wet pavement is a big and little talked about energy drain. The resistance from rain in the air increases drag but the biggest component is that interaction of rolling tires with water on the streets.

Think of following a vehicle closely on the highway. There may be little or no rain at the time but the pavement is wet. You can barely see from all of the water kicked up by the vehicle in front of you. A significant amount of energy is transferred to the water in this process and it is seen in increased rolling resistance.

AoneOne | 1 mars 2014

Some hypermilers "ride the ridges" driving toward the edge of the lanes to avoid driving through the rain-filled ruts worn in highways by the generally-centered traffic.

Koz | 1 mars 2014

Some do it to avoid hydro-planing.

Bighorn | 1 mars 2014

Some go side to side to practice their half-pipe.

Brian H | 1 mars 2014

Cute! Seen any 1080s?

mbcaffe | 3 mars 2014

thanks for everyone's comments.

Out4aDuck | 3 mars 2014

Just as a point of interest, high humidity air (not counting liquid water that might be suspended in it) is actually less dense than low humidity air.

Earl and Nagin ... | 3 mars 2014

Remember that tires are designed to move water out of the way of rubber so that rubber contacts the road. This is why they have the channels in the tread. Moving that water is essentially pumping a lot of water mass out of the way which of course uses additional energy, reducing fuel economy.

Brian H | 3 mars 2014

Think of water as thin glue trying to stick your tires to the pavement.