I finally figured out a sensible way of driving my Clarity Hybrid in the mountains.
My typical trip is a 200-mile, 3-hour drive from Oakland, CA to Tahoe City. The first 2/3 of the trip are flat freeway. The last 70 miles or so consists of steep climbs alternating with downhills. The summit is at 7,000ft, so the total climb is considerably higher. None of the existing drive modes works well:
1. Electric mode runs out of energy very quickly.
2. Hybrid mode works fine at the start of each climb, when both ICE and electric motor work together. But halfway through each climb section, the regulator figures that it's time to recharge the battery. So now the ICE is both pushing the car up, and recharging the battery, and runs at very high RPM, which is less efficient and will shorten its life.
3. Recharge mode is even worse, as the ICE tries to recharge the battery at a higher rate than hybrid.
In both hybrid and recharge mode, it's infuriating that the ICE stops recharging in the downhill sections, when it could recharge with little effort, and instead goes idle.
What Honda should really provide is a "electric with gas assist mode", or "lenient hybrid mode". A driver can emulate it like this:
1. Set the mode to "hybrid".
2. Set the display to show instantaneous MPG (or pay attention to the ICE whine) so you can tell when the ICE starts recharging the battery (usually in the middle of a climb).
3. At that moment, turn hybrid mode off, then turn it back on.
What happens is that cycling out of hybrid mode and back in resets the "target" charge level to the current level. The regulator allows the charge to go below the target level before it takes action again.
On this particular route, one cycle is enough for most climbs. (I don't remember exactly, but it is possible that I used two cycles on one or two particularly long climbs.) Using this technique I was able to reach the summit with about 1/3 charge capacity left. Since the climb takes one good hour, this puts less strain on the battery than driving electric only. It also puts considerably less strain on the ICE.
I really see no downside to automating this mode, and I think it's an engineering failure of Honda for not offering it.
My typical trip is a 200-mile, 3-hour drive from Oakland, CA to Tahoe City. The first 2/3 of the trip are flat freeway. The last 70 miles or so consists of steep climbs alternating with downhills. The summit is at 7,000ft, so the total climb is considerably higher. None of the existing drive modes works well:
1. Electric mode runs out of energy very quickly.
2. Hybrid mode works fine at the start of each climb, when both ICE and electric motor work together. But halfway through each climb section, the regulator figures that it's time to recharge the battery. So now the ICE is both pushing the car up, and recharging the battery, and runs at very high RPM, which is less efficient and will shorten its life.
3. Recharge mode is even worse, as the ICE tries to recharge the battery at a higher rate than hybrid.
In both hybrid and recharge mode, it's infuriating that the ICE stops recharging in the downhill sections, when it could recharge with little effort, and instead goes idle.
What Honda should really provide is a "electric with gas assist mode", or "lenient hybrid mode". A driver can emulate it like this:
1. Set the mode to "hybrid".
2. Set the display to show instantaneous MPG (or pay attention to the ICE whine) so you can tell when the ICE starts recharging the battery (usually in the middle of a climb).
3. At that moment, turn hybrid mode off, then turn it back on.
What happens is that cycling out of hybrid mode and back in resets the "target" charge level to the current level. The regulator allows the charge to go below the target level before it takes action again.
On this particular route, one cycle is enough for most climbs. (I don't remember exactly, but it is possible that I used two cycles on one or two particularly long climbs.) Using this technique I was able to reach the summit with about 1/3 charge capacity left. Since the climb takes one good hour, this puts less strain on the battery than driving electric only. It also puts considerably less strain on the ICE.
I really see no downside to automating this mode, and I think it's an engineering failure of Honda for not offering it.