So, in fear of being seen as an unquestioning evangelical electric car proponent, I decided to mention anything negative I could see about being the owner of this new electric car. In this posting, I'm throwing away any such double-think and just say it as I see it, good or bad.
Truth is, I struggle to find much that is truly bad about the experience. Most of what I wrote last time consisted of inconsequential minor niggles. Some of them have been addressed. What is easier to write about is how much I am loving the experience.
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| Having got me to work, my Leaf is safely parked in its place, wing mirrors tucked in. |
But if what you want is something simple, quiet, smooth and powerful; something to get you to work, to the shops or to your loved ones without noise or hassle, a modern electrically-powered car has an awful lot to offer.
As a friend pointed out, it's just a car and it feels like a car, a normal well-appointed family car. Yet the acceleration at the low end is surprisingly good. Without having to play clutch against accelerator pedal and without waiting for a growling engine to rev up to speed, you just drop the accelerator pedal for the Leaf to firmly push you back in your seat and take you off from the lights smartly, cleanly and quietly.
The first time I entered the Clyde Tunnel from the tight slip-road bend on the Govan side of the river, I found myself having to quickly get in sync with traffic occupying the left lane, traffic you don't get to see until the last moment due to the layout of the approach. A dab on the pedal and, whoof! I was where I wanted to be in the traffic flow without effort or so much as a whimper from the car.
Braking new ground
In my last blog, I voiced some discomfort with the brakes of the car. My view is changing, partly through increased experience as my muscle coordination is rewired for the different response; but that's not the whole story. The way an electric car works and the way I drive it have much to do with this plot.Cars that don't require the driver to manually change gears are normally called automatics. This is fast becoming a misnomer. Truly automatic cars have a mechanism to change the gears on the driver's behalf. These gears are required because an intermittent combustion engine has a very narrow power bandwidth. It's not good at working when turning slowly, nor when turning fast, so we change the gearing between the engine and the road in steps to keep the engine turning at speeds where it is most comfortable and most capable at converting fuel to energy. We either do this manually or have the car do it automatically for us. In an automatic, to go forward, you select 'D' for 'Drive'.
A very small number of cars, while still changing the gearing between the engine and wheels, do so on a continuous basis rather than in discrete steps. Cars with these types of continuously variable transmission (CVT) are still automatics because the car decides what ratio to use at any moment, not the driver. Hybrid cars use various technical tricks to do what they do, but they are essentially CVTs.
At first glance, electric cars seem to be like conventional automatics. They do not require the driver to change gear and there are only two pedals; a brake and an accelerator, just like in an automatic. But unlike the automatic car, the electric car does not need to change gear on the driver's behalf. This is simply because there is only one gear. That's all! A simple, step-down, reduction gear.
Unlike the intermittent combustion engine, the electric motor has a very wide power bandwidth. It's happy to provide the lashings of torque called for when pulling away from the lights and it's equally as happy providing the power required to keep a car breaking the speed limit down the motorway. The interesting part comes when you take your foot off the accelerator.
Like a conventionally-powered car, the electric car will slow down, and it will do so faster than if it were merely coasting, a familiar concept from conventional motoring. The ICE car slows down because an engine starved of fuel acts as a brake on the car. It's full of sources of friction and it is constantly compressing litres of air for no particular reason. We've all become used to this 'engine braking' effect.
The reason that an electric car slows down when you back off your foot on the accelerator pedal is entirely different. It's based on what happens when the way an electric motor works is reversed. Using principles demonstrated by Michael Faraday almost two centuries ago, if you mechanically rotate the rotor of an electric motor, it can act as an electricity generator. Electric cars utilise this fact by using the car's momentum to turn the motor and in doing so, generate significant amounts of electricity. This power can be used to recharge the battery. Moreover, the engineers can set the degree to which this regenerative braking occurs.
In an electric car or hybrid, there may be an alternative to the 'D' setting - the B setting. In Drive, when you lift your foot off the accelerator, the car slows a little more than if it were coasting, and a small amount of electricity is generated. Further slowing is achieved by use of the brake pedal which increases the regenerative braking and/or uses the brake pads and discs. This was how I drove the Toyota Yaris Hybrid. The balance between the small braking effect from taking the foot off the accelerator and the braking effect by putting it on the brake pedal was well judged. I never used the Yaris B mode because I found it to be too aggressive for my liking.
In the Nissan Leaf, the braking in Drive mode is very similar to the Yaris but the footbrake is too light at the start of its travel. I didn't like the feel of this. Then I tried driving the Leaf in the B mode. This is very similar to the Tesla. In both cars, although the regenerative braking is aggressive to make lots of power for the battery, the degree is well judged. Essentially, the accelerator pedal becomes a speed control pedal because most of the deceleration is also handled by this pedal.
It's like the right pedal has a continuum from high acceleration when fully depressed to mild braking when the foot is taken off. Somewhere in this travel is a point where power is neither been added or taken away from the wheels and you're essentially coasting. The foot brake is then only needed when a large braking effort is required or to bring the car to a complete stop. If I anticipate properly while I drive, I'll do almost all my speed control without having to touch the brake pedal. The brake pads are going to last a long time.
It seems to me that this is where the Leaf is getting it right. The light initial braking on the foot pedal makes sense if the car is already applying a high degree of regenerative braking in B mode. In fact, I've quickly settled into preferring B mode over the Drive mode at all times.
Other pleasantries of the car include its automatic wipers for which I've found the sensitivity setting I'm happiest with. The automatic headlights are also great. I've discovered that it brings them on and dims the displays when I enter the Clyde Tunnel. Neat. I found the button on the door that pulls in the wing mirrors when I park.
I've still to find out how to bring on the sound effects that the car uses when moving slowly, though I'm not sure it can actually do that. I did find out how to change the sound effects it makes inside the car when you switch it on or off. I've put them off as I can't stand the song and dance it makes when you just want to go somewhere. I've yet to try out cruise control; partly because I've still to take the car onto a motorway, but mostly because I've never used cruise control before and I want to read up about it in the very thick instruction manual.
Charge point blues
Meanwhile, a chap from Chargemaster has just been to the house and installed a 32-amp charger just in front of where the car sits. And this has hit me with a negative moment in my electric experience,
The UK government has subsidised my charge point for about 75% of its cost. I was told by Chargemaster that I can claim the remaining cost, £290, from the Scottish government via the Energy Savings Trust Scotland. However, I've just discovered that I missed the boat. You have to claim before the point is installed. Chargemaster had told me they would provide the quote that was required for me to send to the EST. I was waiting for that quote, not realising that time was running out. Having spoken to Chargemaster and the Energy Savings Trust, it seems they might make an exception. I'll let you all know.
Meanwhile, I'm biased and I'm loving the car.
Like you, I like to know what is happening with my car, and how it works, and then I drive accordingly. For example, a few years ago I learned that modern cars use zero fuel when using engine braking, meaning you'll use less fuel going down a hill in gear, than you will just rolling. That was news to me. Using this info, I was able to increase my average fuel economy on a run - e.g. in my 11 year old saloon car, I can get 70mpg between Cumbernauld and Milngavie. Someone else driving my car would probably get about 55mpg.
ReplyDeleteI also learned that a constant throttle opening is best rather than on-off. This is hard to do, even when you know you're meant to be doing it. Cruise control really helps!! I suspect if you use your cruise control when you can, your range will go up.
MY QUESTION IS - what about someone unlike you or I, who hasn't a clue what's going on or why, and just zooms up to the car in front and slams the brake on etc. Leccy cars are going to have to cope with this scenario, as it will be most drivers once they enter mainstream...
Interested in your thoughts.
I learned a long time ago that maintaining a constant accelerator setting was beneficial to a car's consumption. I've noted how other drivers have a setting that constantly oscillates around the ideal.
ReplyDeleteI think the wide adoption of electric cars will lead to a change in driving habits as the more twitchy, aggressive drivers use the low-end torque to nip in and out of traffic. There will be a few accidents that follow from this, unfortunately.