Hi. I'm throwing this question out to the group to see if you can think of a solution that I haven't thought of yet. Changing residences recently, I now start my work commute off on top of a hill. It’s .5 miles down a moderate (guessing 10%) grade. After that I’m back on an uphill/flat drive the rest of my 5 mile drive to work. Obviously about halfway down the hill my engine starts. Because my round trip to work is 10 miles, I really don’t want this to happen. Attempted solutions: Don’t give the car a full charge at night. I’ve tried this to varying success. The difficulty is how precise I need to be given that I can’t take a full charge, yet I also need enough juice to travel a full 10 miles on hills and on the highway. Given that I leave the house within a 10 minute variance each day, that I arrive home sometimes empty (when I run errands after work) and sometimes with charge left, and that temperature changes affect how quickly the car charges, it’s really hard to manipulate the charging timer well enough to always give me that 95% full charge (meaning consumer facing full, not actual SOC full) that I need to accomplish my goal of driving to work and back gas-free. Drive slowly down the hill. So far I’ve been unable to consistently replicate this but I’ve observed occasions where I’ve made it down the hill without the gas engine coming on when I kept the car under 30 mph. Unfortunately it was also a time when I got lucky and hit a 90-95% full charge, so I’m not sure which factor was the cause of my success. Thus I don’t know if this works or not. On a full charge this morning I kept it under 30 and the engine came on half way down the hill, so I’m concluding that this probably won’t help. What else can I do? It’s a stupidly small problem but it really bugs me because my round trip commute is within the car’s range yet I still have to use gas every day. L
Sounds like you need a bigger battery to get back up the hill. maybe there is something on the market that could go in the cargo area. Here's a link, but I have no corroborating information: Plug-In Conversion Specifications, Features, and Warranty | Plug-In Supply
At the risk of prematurely wearing out your brake pads, put the car in neutral prior to descending the hill. It won't regen and the battery can be fully charged at night.
This is what I do, esp in the winter (well, below 52F or thereabouts) where the cold pack doesnt like to take as much regen. When its warmer in the mornings, I usually start coasting (foot off accelerator and brake) at about 35-38MPH (at the top of the hill), but the car never exceeds about 40-42MPH while going down my particular hill. When I reach 0.1 EV miles of what it showed for a full charge (so if it was 12.0EV when I left the house, I'll regen until 11.9EV), I'll either put it in neutral or apply the brakes harder (to engage the friction brakes) before coming to a stop at the Stop sign. Sounds like a lot to keep in mind, but this is pretty much what I've been doing since I owned the car (26 months). Its become second nature. In fact, when I drive our minivan, I have to remind myself not to worry about the ICE coming on.
Interesting. Thanks! So you're saying when the car is in neutral it does not use any regen when I apply the brakes, and instead any brake pedal depression is transferred directly to real brake application, and not regen efforts?
Correct! I have the same situation and have "calibrated" where on the hill to switch into neutral so that the ICE doesn't start as I use a little EV before getting to the downhill run. If I'm going back up the hill still on an all-EV trip it costs 2.5 EV miles to go 1 mile at about 35 mph
This is an artificial "problem" created in your mind only. If the ICE doesn't start going down the hill, it WILL start a short time after you reach the bottom.......so the difference is likely to be tiny indeed.
Is the ICE actually STARTING, or just spinning for braking purposes if the battery is topped? My understanding is that this consumes no fuel, so it's really just a "Jake Brake." Am I missing something?
It doesn't make any difference when it starts if you don't want it to start at the beginning of what would otherwise be an all EV trip. Anything that causes the ICE to spin will initiate the warm up cycle. Regen that would over charge the battery will do it every time.
Or perhaps there's another way down the hill. I have such a route and use it whenever I'm going any near that general direction. It has some ups with the downs, great EV miles.
Does B mode start the ICE on gas? There was a comment in another thread that it uses ICE compression but with no fuel.
I am in the same situation as I live at the top of a hill and have a 2 mile drive to work. I use the neutral method. So long as you are aware that you are effectively 'shifting' the car when driving in this mode, it's perfectly safe. To others, yes, the problem is that once the ICE starts, it has to run through the entire warm-up period, which wrecks fuel economy on short trips.
