Optimum EV Speed

Optimum for what?

 

The electric is pretty linear. However anything using less than 11 HP is considered a sweet spot but the only way your going to see that gauge is by going to HV mode.


iPad ? HD

 

Yea! thats about the best, if you are not holding up traffic! Good luck with that one!

 

Most miles per kWh of battery charge. Sounds like a good number. I do a lot of 25mph and 30mph on city streets.

 

where are you getting the 15-18 from? i don't recall seeing that anywhere.

 

I have no idea, I just figure anything from about 15-25 if possible is going to be as good as it gets!

 

thank you, i must have missed that.

 

I just drive what the street allows. No need to rev anyone up.

 

I concentrate more on timing signals and watching traffic in order to avoid having to accelerate from unneccessary stops. On city streets I keep to the right at around 35 mph, and usually get about 14-15 miles on a charge before any use of the ICE. I can see where driving at 15-18 mph would impede traffic and really make people angry.

 

Been wondering the same here. On the very slowest end, near 0 mph, rolling resistance would be an obstacle to high EV range on a single charge. However, the faster one goes, wind resistance becomes more of an issue. Intuitively, speed in the teen mph range sounds right. Anyone here have some real data/calculations? I agree with retired4999 - traffic makes this an untestable question for most of us.

 

On our small back country roads where no traffic is, I have on many occasions used 24mph.
This is the slowest speed Cruise Control can lock in at. I could have gone slower but have not gained much EV distance.

I can get 17+ EV miles everytime at 24mph. And its nice using CC not having to modulate with your foot.

Try to keep your HSI indicator bar at the very bottom, since the higher the indicator bar is the more battery you use.

 

Thanks! Looks like Ken came up with 14-15 mph for max EV efficiency (kWh/mile). Also, looking at his figures, one loses almost 19% going from 15 mph to 30 mph. Meanwhile, driving within 10-20 mph keeps one within 3% of maximum efficiency. Now if only our PIPs could drive on autopilot so we could read a good book as it would take an eternity to drive anywhere at this speed. And there is still the problem with the angry line of vehicles honking behind us.

 

Does this help? The data is for a Tesla Roadster. However, I at load speeds I assume little difference in Wh consumed between different vehicles. The data suggests the best strategy is to accelerate quickly to 15 mph.

 

This graph seems a little optimistic for the Prius perhaps by a factor of 2. It certainly gives a good idea of how miles/kWh varies with speed.

Prius battery 4.4 kWh
Usable SOC range 20% to 85%
Usable kWh 0.65 * 4.4 = 2.89 kWh
From the graph
135 Wh/mi at 20mph >> 2.89*1000/135 = 21.4 miles at 20mph
175 Wh/mi at 40mph >> 2.89*1000/175 = 16.5 miles at 40mph
250 Wh/mi at 60mph >> 2.89*1000/250 = 11.6 miles at 60mph

 

My best is 17.3 miles on one charge, cruise set to 25 mph. W/o cruise, and coasting in neutral down the hills with an average speed of 19 mph, I made 19.3 miles on the same route. Scangauge shows what I would call parasitic discharge while coasting in Drive mode. There is 0.8 to 1.3 kW drain in glide, while in neutral, the discharge is 0.2 kW. So, by coasting in neutral, some energy is saved. Fortunately for me, I live in rural Amish Country, WI. Almost no traffic. Haven't been passed by a horse and buggy yet. Some say THEY are low emission, but I've driven through their 'emission' a few times, and it stinks.