JasonT wrote:I don't see what is wrong with some regen braking happening when you let off the accelerator.
You have not driven a Prius on a regular basis have you. Gary 'complained' in the following post about having to hold very light pressure on the accelerator pedal to coast. That is one feature I REALLY hope Nissan has implemented in the Leaf. A larger dead band would be really nice as he is right, it can be hard to hold.
First, in PriusChat land, Gary's description is referred to as 'gliding', not 'coasting'. The difference is that when 'gliding' there is no power going to the wheels and no drag through the electric motor (regen) slowing the car - only rolling and wind resistance. Coasting implies regen in the Prius, engine drag in ICE vehicles. Both slow the car much more quickly than effectively being in neutral.
What is wrong with coasting regen? Nothing (if you WANT to slow down) but there are conversion losses. The conversion in a Prius is about 80% efficient. For every 100 Watts you generate, only 80 get into the battery and only 64 come out. Every time you slow down using regen you lose potential energy you have paid for with your Leaf battery, in this case 26 Watts.
There is a full mile of my 10 mile commute to work where I can glide - using no gas, using no electricity - at the 40 MPH speed limit. If I could not glide, I would be using gas or electricity unnecessarily. Thus, if the Leaf is not 'glide capable' my 'fuel' use would unnecessarily increase by 10 % and my range decrease by 10%. I can approach lights that are going to turn red in 'glide' making more distance 'free' than if I was regen coasting starting closer to the red light. If you live on the dead flat there is less gain, but the ability to glide would extend the range of a Leaf, perhaps substantially, for many.