Preparing for winter with a comprehensive strategy to improve MPGs including grille blocking & more

[lsherlockl]

So last nights return trip and this mornings both averaged ~38.5 i must say im somewhat confused/disappointed (i know as stated gas is cheap atm) i feel like I am doing something wrong. Engine temp is solidly half way in the recommended zone, with or without HVAC on alot of stretches i see the ICE running at the first "tick" ime like wtf the battery is almost full why arent you using electric. and its on a flat stretch too. The sort of car monitor on the big display dosnt say engine is on for heat or anything, it just says acceleration but its hardly accelerating just maintaining a bit.

 

I guess i just don't get it, maybe i am getting to hung up on fuel economy ;) (i know i totally said i wouldn't when i got the car)

 

Ill also go and try the feet/shield technique on the HVAC, first morning it actually started fogging bad. Must have just had low humidity the past few days.

[corncobs]

I don't think you are doing anything wrong it's just damn cold and nothing we can do about it.

 

I "only" managed 39.8 MPG this morning but considering its -6*F out there not bad if you ask me.

[acdii]

Your right on the money there at 38 MPG. With the temps we have right now in - numbers, the battery takes a long time to warm up, and the computer wont allow full use of the battery until it reaches a threshold temperature. This is why you see a full battery yet the ICE comes on almost immediately.

 

LION batteries only work well in a certain temperature range, so they rely on cabin temps to warm and cool them for peak efficiency. Once your cabin warms up, then the EV thresholds will increase and use more energy from the pack instead of ICE. Over the past 2 years with the HyTi I noticed a couple things that are different than the Gen 1 Fusion and Toyota system. Due to the fact the new Ford system is EV to 85, you no longer travel on ICE only above 45 MPH. In the previous gen and Toys when you are above 45 the ICE stays warm so your heaters work well, the ICE is at a constant temp so MPG can increase with high speed driving.

 

Up to 85 MPH the 13+ system switches between both EV and ICE so the ICE can quickly cool down, this is where the grill blocking becomes very important, to keep the flow of cold air out of the engine compartment to prevent chill down of the components and radiator.

 

Ran out of time, will add more later

[hybridbear]

Acdii is right on the money. The other big factor with these cold temps is the internal friction factor. As the temperature drops the internal friction in the eCVT increases due to the viscosity of the fluid. This can cause up to a 30% increase in the energy required to propel the car per testing done by Larryh.

[lsherlockl]

hmm so would increasing air flow to the battery, ie dropping the rear seats help the battery warm up faster? I guess that sorta makes sense i see the electric motor come on a bit alongside the ICE when cruising, most likely to warm up the battery due to the heat created in current transfer too.

 

I guess i can be satisfied with what i'm getting at the moment then too. still a few more things to try out and test yet.

 

This car really makes you think! I like that :)

[Texasota]

I guess i can be satisfied with what i'm getting at the moment then too. still a few more things to try out and test yet.

Your MPGs will see a substantial improvement when warm weather returns. But, 38 MPG is fantastic MPGs for a comfortable midsize sedan in the Wisconsin winter. Chill until warm temps return. ;)

[jeffo65]

I'm doing essentially the same thing except I keep the HVAC in manual control.

 

Air goes to the windshield and the feet (acdii's approach) and depending on the engine temp and the ICE usage the fan either really low or high if there's enough heat available.

 

It's hard to turn it off completely since the windshield is fogging over rather quickly. Therefore I keep the fan at 1 bar for the most part and the temp setting at 69*.

 

When it's that cold the worst thing is stop and go traffic because the ICE constantly runs to provide heat with no travel. Like last night IIRC (I knew it was gonna be low) the trip home after crawling on I-290 because of an accident return 33.4 MPG.

 

This morning with better flowing traffic 41.9 MPG.

 

The gallon of regular was only $1.869 last night so nothing to worry about except the personal pride not getting at least 40 MPG. ;)

.

 

We do exactly the same thing. The only difference is that gas is $1.69 at the moment. :)

Edited January 8, 2015 by jeffo65

[hybridbear]

Wow! Our gas in MN is still close to $2.00 per gallon. I can't believe how much prices have fallen. But, we have a huge topic devoted to gas prices, we don't need to talk extensively about them here. We can do that in this thread if we'd like: http://fordfusionhybridforum.com/topic/6584-gas-prices/

[lsherlockl]

Your MPGs will see a substantial improvement when warm weather returns. But, 38 MPG is fantastic MPGs for a comfortable midsize sedan in the Wisconsin winter. Chill until warm temps return. ;)

 

i see what you did there....

 

yeah i guess its just wishful thinking to see over 40 all the time.

[ptjones]

Some interesting info on premium gas from Consumer Reports here:

 

http://consumerreports.org/cro/magazine/2012/08/debunking-fuel-economy-myths/index.htm

 

They stated this about performance from premium gas:

 

 

Even if there was a measuarable improvement in MPGs from premium gas that would most likely be negated by the increased cost per gallon.

For me it's only 32 cents a gallon more, well worth it and it always improves my MPG's. :)

 

Paul

Edited January 8, 2015 by ptjones

[lsherlockl]

so the past 2 days i have been playing around with the whole battery temp thing concept. I folded down the 40 of the 60-40 split rear seat. Set temps to 69 oscillating fan speed based on engine temp with it on def and feet. So far it seems promising been breaking the 40mpg mark i think it does help a bit to get more air to the battery? i point the rear vents at the opening too. Also been keeping the sunshade closed when there is no direct sunlight to help solar warm the interior.

[acdii]

One other thing I have found. I would say at least 2/3rds of my daily drive is at 55 MPH. In the summertime weather, I would see it get over the 40 mark rather quickly, and if I were to use EV, the recharge rate is much faster, so it doesn't stay below 40 for very long. In winter driving though, cold soak happens quickly, so it takes much longer to get up to 40 and rarely over 40 at 55 MPH, so I limit EV as much as I can since any EV driving turns off the ICE which quickly loses temp, so when it switches back to ICE, it not only has to propel the car, recharge the battery, but also has to warm back up, so it takes much longer to get back up to near 40.

 

I also drive a few miles before turning on the HVAC, which is set to auto, keeps that blast of cold air from chilling us, when it kicks on now its a blast of warm air and feels pretty good. My techniques may not work for the majority of drivers since they may not be driving on Rural highways for 30 miles. But for those who leave their driveway and speed up to 55 MPH and stay there for a long time, my techniques seem to work pretty good. So far its keeping me right around the 38-40 range. Summer is 43-48 range. I don't expect more out of it, and certianly not less, but the occasional 35 doesn't bother me, if it is that low, it usually means it is really cold or the roads were really bad.

[ptjones]

One other thing I have found. I would say at least 2/3rds of my daily drive is at 55 MPH. In the summertime weather, I would see it get over the 40 mark rather quickly, and if I were to use EV, the recharge rate is much faster, so it doesn't stay below 40 for very long. In winter driving though, cold soak happens quickly, so it takes much longer to get up to 40 and rarely over 40 at 55 MPH, so I limit EV as much as I can since any EV driving turns off the ICE which quickly loses temp, so when it switches back to ICE, it not only has to propel the car, recharge the battery, but also has to warm back up, so it takes much longer to get back up to near 40.

 

I also drive a few miles before turning on the HVAC, which is set to auto, keeps that blast of cold air from chilling us, when it kicks on now its a blast of warm air and feels pretty good. My techniques may not work for the majority of drivers since they may not be driving on Rural highways for 30 miles. But for those who leave their driveway and speed up to 55 MPH and stay there for a long time, my techniques seem to work pretty good. So far its keeping me right around the 38-40 range. Summer is 43-48 range. I don't expect more out of it, and certianly not less, but the occasional 35 doesn't bother me, if it is that low, it usually means it is really cold or the roads were really bad.

How about completely closing off the front end with tape? You shouldn't lose much ICE heat and you can use heater to control ICE temp and heat the cabin. That's what I did with good results. IMO :)

Paul

Edited January 20, 2015 by ptjones

[acdii]

i would if I were to get anal about it. Right now we are comfortable in the car, it runs good, and gets what I ask out of it. In fact the top piece of foam flew out on my wife, and I have been too lazy to fit a new piece in(that and the wife has the trunk full of paperbacks covering the foam). I do notice a slight drop from when it was 100% covered, but not enough to worry about yet. When temps dip to single digits again then I will fit a replacement in.

[Texasota]

In fact the top piece of foam flew out on my wife, and I have been too lazy to fit a new piece in(that and the wife has the trunk full of paperbacks covering the foam.

Come on, fess up. The romance novels filling up the trunk are yours.

Edited January 20, 2015 by Texasota

[tr7driver]

His idea of a romance novel may be the owners manual for his Fusion. :yahoo:

[acdii]

Well if you consider Tom Clancy, Dale Brown, Stephen Coonts and Clive Cussler romance writers...........

[lsherlockl]

I must say after doing allot more driving, and getting better at driving a hybrid (not rally anything too special to it but understanding what the car is thinking vs me). With my upper grille packed with foam I am happily getting ~45 the past two tanks in this much warmer weather of 20F, I happily seen a few commutes get 49.5mpg (something i thought not very possible) I imagine it was the super cold -0F temps that had me being irrationally upset. Hopefully this car will impress even more during the summer!

[acdii]

In the cold I am seeing a drop of about 3 MPG, where I normally get about 43 or so I get 40 or so, and where I was getting 40 around 38. Overall not bad at all.

[hybridbear]

Here's a great post by Larry from the Energi Forum talking about why it takes more energy to propel the car in winter:

 

In the summer, the usable energy from the HVB is around 5.7 kWh before the ICE turns on (maybe up to 6.0 kWh of you are careful). For my commute to work in the summer, the car consumes about 0.23 kWh of energy per mile for a range of 5.7/0.23 = 25 miles.

 

In the winter time, the chemical reactions in the HVB slow down. The HVB cannot supply as much energy. When it is around 0 F, the usable energy from the HVB drops to around 5.0 kWh.

 

If I used the heater for my commute at around 0 F, the electric heating element would draw approximately 2.2 kWh of energy from the HVB. Thus the usable energy from the HVB to propel the car drops to around 2.8 kWh.

 

Finally, friction and aerodynamic drag increase by 40% when it is 0 F vs 70 F. It takes a lot more energy to propel the car in the winter. At 0 F, it now takes 0.32 kWh of energy per mile. Thus the total range of the car is now 2.8/0.32 = 9 miles.

 

In summary, you lose the following amounts of range to these various factors in winter at 0 F:

 

HVB capacity falls with temperature: 3 miles

Increased friction/aerodynamic drag: 3.5 miles

Heater consumes energy from HVB: 9.5 miles

 

The heater is the largest source of loss of range. Use it sparingly.

The FFH doesn't have the electric heater, but the heater does consume energy from the coolant which causes the ICE to run more. The principles in the post above all apply to the FFH.

[kbailey990]

How much energy dos the seat warmer consume (at the high setting?) I've been using that instead of turning on the heater. (Of course it helps that I'm in Sarasota )

[acdii]

Seat heater is 12v, the electric heater in the Energi is using the HVB or traction battery. Huge difference.

[Texasota]

Here's a great post by Larry from the Energi Forum talking about why it takes more energy to propel the car in winter:

 

The FFH doesn't have the electric heater, but the heater does consume energy from the coolant which causes the ICE to run more. The principles in the post above all apply to the FFH.

The points in Larry's post all seemed plausible to me except for one thing. Why does aerodynamic drag increase in winter? I can see that if there is a mound of snow piled up on the roof but if the car is clean why less aerodynamic? Is it because colder air is more dense?

 

Edit: I think I answered my own question when I found this page that says much of what Larry did: http://wxbrad.com/why-cold-weather-gives-you-lower-gas-mileage/

 

Point # 7 states this:

 

#7 More Aerodynamic Drag:

When it’s cold you have more drag on your car as the air passes over it. Cold air is just denser than warm air. A vehicle’s aerodynamic drag is proportional to air density, and the density increases as temperature drops. For every 10° drop in temperature, aerodynamic drag increases by 2%. This is mostly at highway speeds and long trips on the freeways.

If 2% aerodynamic drag increase for every 10 degrees in temperature drop is accurate, then that is amazing and not something that I would have thought about. That means in Minnesota (where the temperature can be 90 in the summer and -30 in the winter) the aerodynamic drag increases as much as 24%.

 

Thanks for the post, HB.

Edited February 16, 2015 by Texasota

[Automate]

Finally, friction and aerodynamic drag increase by 40% when it is 0 F vs 70 F. It takes a lot more energy to propel the car in the winter. At 0 F, it now takes 0.32 kWh of energy per mile. Thus the total range of the car is now 2.8/0.32 = 9 miles.

 

For every 10° drop in temperature, aerodynamic drag increases by 2%

 

I'm guessing he meant 14% not 40%, 7 * 2%

[hybridbear]

I'm guessing he meant 14% not 40%, 7 * 2%

Friction also increases. Tires lose air pressure. Rubber stiffness changes as well. The transmission fluid also is much thicker at lower temps which greatly increases internal friction. Finally, snow & ice on the roads increases friction.