When climbing hills and in CC, the HSD has to work pretty hard to maintain speed which of course lowers MPG. It has always seemed somewhat logical to me that an ECO mode setting for CC (on any hybrid or regular car for that matter) would be to allow the car to slow down some on a hill while in CC, like 5 or 10 mph so that the MPG can be partially conserved. Too bad the C doesn't allow for ECO Cruise Control.
Due to an old injury (right foot smashed), I use CC a lot. When climbing the local hills, I know how much the engine load is going be at different speeds. Depending on traffic and approach speed, I know how much to down-click the CC (1 mph increments). I also have feedback from the displays (on my Ford Escape: ScanGuage2), so I'm down-clicking based on the display, sound of the engine/rpm and experience. Depending on the length, angle of accent & speed, I will down-click the CC, chopping my speed, to avoid seeing the MPG dropping under a my preselected MPG (for that hill). My other goal is not to be driving at an unsafe speed at the top of the hill. I want to be very close to the speed limit, so sometimes, my approach might be a bit over the speed limit. Some hills are so steep, I know it's going to get down to 15 MPG. But if just left alone, the CC will take it to 8 MPG! I've found this method works pretty well with the new Prius C, but I'm going to need more practice. I don't think we will ever see a slow-down-on-hills mode in a CC. After a few cars got rear-ended by trucks, (both drivers texting?) it would be declared illegal.
Most trucks slow down significantly when climbing a hill. Why would they plow into a car, assuming traveling in the right lane, if it slowed down 10 mph? Not trying to be argumentative, but I dont see this as a major problem.
If the traffic permits I will build my speed a little when approaching a hill, tap my brakes when the hill starts as to shut off CC, and then try to let my speed/momentum bleed off slowly during the climb while balancing mpg and not upsetting people in cars behind me.
Around here, many drivers using regular CC, aren't going to slow down at all. And, drivers not using CC might have the gas pedal down hard and might, exceed safe speeds near the top, if the hill levels off a bit. The turn onto my street is at the top of a small hill. It's a 30 MPH zone, but we have to be very careful (and quick) when we turn left, across the on-coming lane. When there is traffic, and I've to come to a dead stop before turning, I've have a few close calls, as I've made the turn. Speeders will come shooting over the rise at twice the speed limit, and lock up their brakes. Because they floored it on the way up the hill..
