Driving in L under 45mph

[user 527]

Sales rep at the dealership suggested region benefits from keeping in L under 45 (he might have said 50). I'm still learning about the braking/regen thing. Anyone have a sec for a short tutorial (or point me to one online)?

Heading over to pick up my new Spark this morning!

 

[xylhim]

You'll have to toy around with this when you get it. Many people on the board switch from N to D to L on a routine basis to slow down (even though a dealer would never tell you to switch it into neutral). The best overall tip I have is to use the cruise control whenever possible to try and maintain a constant speed, especially on the highway. For city driving, keeping in D is fine, and you can drop it into L to slow down (I'm coming from a manual transmission, so I like futzing with the gear selector).

 

[SteveC5088]

You can drive in L all the time! I do sometimes. But if you are just tooling around, L will slow you down faster, and put some of the energy back into the battery. If you want to conserve the most energy, you will keep it in D until you really do, intentionally, want to reduce your speed.

That said, I drive in D and shift into L to slow the car as I approach a stop light, only touching the brake pedal for the last 100 feet or so. If I have charge to spare and I want to drive like I stole it, I'll keep it in L most of the time, since every slow-down is one I want to do quickly.

 

[Nashco]

Like these guys said, it's really up to driver preference. I prefer to drive with one pedal most of the time, which means I like to drive in L normally to get the higher regen torque if I let up completely off the accelerator. Some prefer driving with two pedals most of the time, especially those coming from cars with automatic transmissions. It's most efficient to avoid regeneration or brake use at all, of course, but if you're in the city it's usually pretty impractical. Most of my driving is in the city in L. There's no magic speed for using L versus D, it's just up to driver preference.

Bryce

 

[user 527]

Like these guys said, it's really up to driver preference. I prefer to drive with one pedal most of the time, which means I like to drive in L normally to get the higher regen torque if I let up completely off the accelerator. Some prefer driving with two pedals most of the time, especially those coming from cars with automatic transmissions. It's most efficient to avoid regeneration or brake use at all, of course, but if you're in the city it's usually pretty impractical. Most of my driving is in the city in L. There's no magic speed for using L versus D, it's just up to driver preference.

Bryce

Well, in all of my 100 miles so far, it seems to me the regen is most active using L downhill, which makes most sense to me. On level or uphill, the drag counters the regen benefit. Am I right here?

BTW, this morning was my first ev commute to work (40 miles round trip). Starting with 58 miles available, traveling 20 miles and climbing 3500 feet, made it to work showing 21 miles available. When I got home, it appeared I had 43 miles available (a gain of 22 miles on the downslope). It appeared I'd driven 40 miles with a cost of 15. (I'd put it into kWh, but I'm not yet familiar with the translation.)

Did THAT surprise me!

 

[SteveC5088]

Well, in all of my 100 miles so far, it seems to me the regen is most active using L downhill, which makes most sense to me. On level or uphill, the drag counters the regen benefit. Am I right here?

Not sure what you mean: "drag counters the regen". The Spark has very little drag on flat terrain. Try shifting to N and just watch how far it coasts. It is the "L" that causes the "drag", which is the motor/generator sucking energy from the forward motion, and stuffing it (about 80% of it) back into the battery .

BTW, this morning was my first ev commute to work (40 miles round trip). Starting with 58 miles available, traveling 20 miles and climbing 3500 feet, made it to work showing 21 miles available. When I got home, it appeared I had 43 miles available (a gain of 22 miles on the downslope). It appeared I'd driven 40 miles with a cost of 15. (I'd put it into kWh, but I'm not yet familiar with the translation.)

Did THAT surprise me!

The miles remaining is an estimate based on your most recent driving. Since it was descending, it figured you would be descending 21 more downslope. Since that cannot be the case, don't trust the estimate.

 

[user 527]

Well, in all of my 100 miles so far, it seems to me the regen is most active using L downhill, which makes most sense to me. On level or uphill, the drag counters the regen benefit. Am I right here?

Not sure what you mean: "drag counters the regen". The Spark has very little drag on flat terrain. Try shifting to N and just watch how far it coasts. It is the "L" that causes the "drag", which is the motor/generator sucking energy from the forward motion, and stuffing it (about 80% of it) back into the battery .

BTW, this morning was my first ev commute to work (40 miles round trip). Starting with 58 miles available, traveling 20 miles and climbing 3500 feet, made it to work showing 21 miles available. When I got home, it appeared I had 43 miles available (a gain of 22 miles on the downslope). It appeared I'd driven 40 miles with a cost of 15. (I'd put it into kWh, but I'm not yet familiar with the translation.)

Did THAT surprise me!

The miles remaining is an estimate based on your most recent driving. Since it was descending, it figured you would be descending 21 more downslope. Since that cannot be the case, don't trust the estimate.

I meant that benefits of L regen [on flat or uphill] seem not to outweigh the energy costs in drag.

The numbers were after I parked.

 

[emv]

As time goes on you'll learn how to interpret the miles remaining. Personally I like using the enhanced battery gauge (the one with projected max and min figures) as it gives more insight as to how I'm really doing. Time will teach you much.

As far as "L" goes, you'll probably hear as many opinions as there are Spark drivers. I tend to use is going down steep hills so I can use the brake pedal less.

It seems to me that L is set up so that taking your foot off the accelerator is the same as a moderate press on the brakes. As stepping on the brakes brings in regeneration first then hydraulics as required there is little difference in overall efficiency. On flat ground, I get better efficiency using the pedal.

One thing to consider when using "L". In general the brake lights don't come on unless you step on the pedal. At least on ours they don't seem to come on often in L. This could be dangerous as the poor schmuck behind you isn't getting full warning that you're slowing down. Of course, in other cars, I've been rear ended several times while stopped at a red light with my foot on the brakes - so it may not matter.

 

[user 527]

As time goes on you'll learn how to interpret the miles remaining. Personally I like using the enhanced battery gauge (the one with projected max and min figures) as it gives more insight as to how I'm really doing. Time will teach you much.

As far as "L" goes, you'll probably hear as many opinions as there are Spark drivers. I tend to use is going down steep hills so I can use the brake pedal less.

It seems to me that L is set up so that taking your foot off the accelerator is the same as a moderate press on the brakes. As stepping on the brakes brings in regeneration first then hydraulics as required there is little difference in overall efficiency. On flat ground, I get better efficiency using the pedal.

One thing to consider when using "L". In general the brake lights don't come on unless you step on the pedal. At least on ours they don't seem to come on often in L. This could be dangerous as the poor schmuck behind you isn't getting full warning that you're slowing down. Of course, in other cars, I've been rear ended several times while stopped at a red light with my foot on the brakes - so it may not matter.

Thanks everyone. I've got A LOT to learn, for sure and certain. Like what do to with my thoughts, it being so quiet to drive.

 

[genosensor]

Some observations I've made over the past year driving this little beast:

1) Just removing ones foot from the accelerator when the car is moving > 40mph or so in 'L' *will* cause the brake lights to illuminate. Steal a look in your rear view mirror while driving on the freeway at night.

2) If you are careful with the accelerator pedal, you can make the car coast in 'L' (or 'D') by pressing it ever so slightly.
The only real difference between 'L' and 'D' is the mapping of the accelerator position to power in or out of the battery.
'L' has a larger area where the motor acts as a generator. The point where the car coasts is with the pedal further down.
'D' has a very small pedal area where the motor acts as a generator, but it's there.

3) In the Spark EV, anytime one depresses the brake pedal, energy is wasted.
Braking is heavily augmented by the motor/generator, but the brake pads are always actuated when the pedal is pressed.
It's a traditional hydraulic system, augmented by regen -- not blended, computer controlled brake-by-wire.
Which is nice, as it would stop the car even if all the electronics were to suddenly quit.

4) The Spark's unassisted brakes are very "wooden" feeling by design. There's not much initial "bite" to them.
The idea is that, until you press the pedal hard, the motor regenerates without brakes' wasting much as heat.
This is why the car tends to slide forward farther that one would expect at the very end of a stop.
It took me quite a while to get the hang of stopping exactly where I wanted.
Normally, one let's up on the brakes when almost stopped to avoid lurching to a halt.
The Spark EV does the automatically when the car slows to the point where the regen no longer works.

 

[kevin]

Some observations I've made over the past year driving this little beast:
...

3) In the Spark EV, anytime one depresses the brake pedal, energy is wasted.
Braking is heavily augmented by the motor/generator, but the brake pads are always actuated when the pedal is pressed.
It's a traditional hydraulic system, augmented by regen -- not blended, computer controlled brake-by-wire.
Which is nice, as it would stop the car even if all the electronics were to suddenly quit.
...
.

I don't believe that's true - for gentle to moderate braking the friction brakes are not engaged, just regeneration.

kevin