I live in the foothills of the foothills of the Blue Ridge mountain and am pretty much either going up hill or down hill.

In my case the use of cruise control at freeway speeds makes me a bit nervous regarding battery use, in light that I hope to take my car over 300K miles.

The use of battery draining/recharging is substantially more, and cruise control has no problem holding the feed down far enough for 1/2 to 2/3 Assist (Or more) for rather long periods of time.
I've experimented with cruise control on my commute and notice the battery draining well below half 5 or 6 times over the trip.

Given the fact that I can dis-engage and take the hill @ only 4 bars Assist and at no time does the battery go lower than 3/4 normal full.
If it were just one or two hills I wouldn't be concerned but one after another after another makes me wonder.

I can lock the cruise control in at the speed limits of:
12 miles @ 55MPH
15 miles @ 60 (In a 65 limit)
18 miles @ 65 (In a 70 limit)
And park with 51-53MPG,

Or I can disengage and drive the same speeds and get mid-upper 50's.
(On a nice day without storms in all cases)

I can do the same route driving for efficiency and get lower 60's.
Or, as usual I can avoid the 70MPH limits, get off the freeway and use a parallel hightway and milk it to the upper 60's, which costs another 7 minutes including the few neccessary stops.

For me to get my very high MPG last summer my goal to meet was minimum 65MPG dash reading going to work in the afternoon, and 71MPG parking back home.

Cruise, in my case could never dream of such numbers.

 

I was in San Diego once when it was CLOUDY and there were even a couple drops of rain Once I even saw snow on the hills in San Jose.
--Walter

 

Yes, I've noticed that too, although to a lesser degree (my hills are probably gentler than yours).

You know what would be really nice? A CC that slaved to MPG rather than speed (a DWL CC!). Or even just a range to the set point. For example, set to 65MPH +/- 5, so allow it to drop as low as 60, or rise as high as 70. That would probably make a big difference on battery use. I agree though, there's no substitute for a human driver.

In this case are you trying to hold a constant speed, or are you allowing some variance? Are you doing DWL?

 

Not when you leave as much space in front of the car as I do.
I almost never have to take it out of CC.

 

Same in my case ('03 Civic)

Driving with load at 60-65 MPH on the I-5 in Orange county (lots of long, gradual hills)

My typical drives are 15-20 miles one-way, two of those miles (one-way) over hilly residential streets which net me <30mpg up (I can get just over 30 with an absolutely full pack on a warm day, since I don't hit force-charging before the top) and <60mpg down (cold start). I also make short lunch trips, and have to deal with idling in a big parking lot every day. As a result, I average in the low-mid 50s overall. Still pretty good I'd say (I averaged 39 before I paid attention to technique)

 

About the battery discharge from CC.
It must depend on the severity and length of inclines.
My battery never falls below about 80% charge.

 

NASAgineer; I have one thing to say to you. Thanks for this test of yours with the cruise control because I really think that the vast majority of us drive at those different speeds according to what and where we are going and I think we also try to use our (Cruise-Control) if possible. This I think is the most down to earth test that I have seen anyone do so far and I can tell you I bet a bunch of us that own and will own the HCh ll cannot tell you how much we appreciate what you are doing. For the majority of us this is the (Real-World). "IMO"

Thanks-Again:

Terry

 

Day 2 (70 MPH)

Home -> Work

Trip Mileage: 46.2 MPG
Set Speed: 70 MPH
Temp: 57 (start), 58 (end)
SoC: 88% (start), 88% (end)
Time: 30 minutes
Notes: Full speed trhe whole trip

Work -> Home

Trip Mileage: 43.6 MPG
Set Speed: 70 MPH
Temp: 61 (start), 55 (end)
SoC: 88% (start), 88% (end)
Time: 32 minutes
Notes: Full speed the whole time

I have no idea what caused the difference between the two trips. Wind was non-existent in both cases.

Tomorrow, 80!

 

Thanks Terry. I'd be interested to hear if others get similar results.

 

Hi NASAngineer:

Day 1 (60 mph average) = 51.7 mpg
Day 2 (70 mph average) = 44.9 mpg
Day 3 (80 mph average) = xx.x mpg

___80 mph

“Get out of the way, please, oh my, this is terrible...Oh, the humanity”



___Oopps, my bad. We were talking about the Honda-hybrid, not the Hindenburg

___Good Luck

___Wayne R. Gerdes