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Old 04-28-2017, 06:00 PM   #4 (permalink)
RedDevil
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Join Date: Dec 2012
Location: Nieuwegein, the Netherlands
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Red Devil - '11 Honda Insight Elegance
Team Honda
90 day: 55.71 mpg (US)

It - '09 Hyundai I10 Active Cool
Team Hyundai
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I can provide some insight, mainly how my own Insight behaves

As you know the regenerative energy you can harvest at higher speeds easily exceeds the capacity of the battery. But you need not worry as it gets limited to a safe level by the electronics.

My Insight has a permanent charge/discharge indicator which shows whether I'm on its limit or not. If the needle dips to the deepest part of the green zone (I need to mildly press the brake pedal to make it do that) it is on max regen, and any more pressure on the brake pedal will make it use the disk brakes.
No doubt the Highlander has a feature like that too.

So, if I need to come to a stop and I have the space to do so I just keep it slightly below max regen until the speed is low enough to coast the last bit without braking, retaining some speed for if the lights go green before I get there.
If I need to brake harder I do that in the first phase, aiming to bring the speed down to where I can slow down using only regen for the last part. Doing so, I max out the time I can have max regen as I would take longer (in time) to stop than if I brake overly hard in the last part.

That said, for max regen you need to gradually build up the brake pressure as the speed slows.
A very light touch on the brakes will send it completely in full regen at highway speeds.
At 20 mph you need to brake quite hard to get full regen; power is force times distance per second, so the shorter the distance the higher the (braking) force needs to be to produce the same power.

If I leave the highway and need to brake for the lights and they come up faster than I can manage with just regen, and there is nobody on my ass I can either:
- brake hard to shed excess speed, then gently to brake only on regen, which gradually becomes harder and harder braking as the speed drops, ideally ending in very hard braking right at the lights, or:
- brake even harder to get well below the ideal speed, then leisurely let it roll towards the lights rather slowly, hoping they turn green before I arrive there to retain some of the speed.

The latter holds the risk of the lights turning green before you expect them to, and red again before you arrive. Like it happened to me twice this afternoon; though that was more a case of letting the pack of cars chase away from me and seeing the last of the group dive through at stale orange. But I could have known I'd miss it and let go earlier for less gas usage and more regen... So hard to get it perfect every time.
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2011 Honda Insight + HID, LEDs, tiny PV panel, extra brake pad return springs, neutral wheel alignment, 44/42 PSI (air), PHEV light (inop), tightened wheel nut.
lifetime FE over 0.16 Gmeter or 0.1 Mmile.



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