by chrismb » Wed Jul 17, 2013 6:20 pm
Oh, I always run tyres at between 15 to 10% under their max inflation pressure. I've run multiple sets of tyres, wearing them down from fitment to throw-away at 3mm of tread, and anyone who says it'll end up with uneven tyre wear in the centre is talking out of their hat. Makes no difference with modern tyres. If anything, they wear more evenly because there is less compression as the wheel tilts on its castor angle, so less wear on the shoulder blocks.
Electricity is 14p/kWh here (after taxes), ~20c/kWh. We have various flavours of 'off peak' type tarrifs where you get a lower rate at night, but a higher one in the day time. I looked through the general nature of these pricing options some time ago when previously pondering EVs, and I came to the conclusion that it makes such little difference as to make it more hassle than it's worth, especially when it may well prove to be more convenient to control the charging by doing it earlier in the evening, rather than charge in the small hours and find it is pouring with rain in the morning and all you want to do is run to the car and jump in! I think the flexibility of not having to worry about charging up at particular times of the day probably pays for itself in terms of any 'loss' in relation to what small amount might be possibly saved.
That'll come out in the wash, of course, when I actually see the electricity bills come in. Should be adding no more than GBP15 to 20 per month. If it ends up more than that then I'll have to do some investigations as to the best way forward with the options available.
Yes, this is a product of the Renault-Nissan effort, and will be using the same motor (but this one is derated compared to the Leaf) and the same battery tech [Edit: Not true!!! - see my update below]. The Fluence is based on an existing vehicle, so the non-traction bits are all mainstream stuff. Obviously, to be removable it is a vertical single block battery pack in the Fluence whereas it is spread out in the Leaf.
Interestingly, so far as I have heard, with the motor/inverter stuff in the front and batteries in the back, the Fluence has been designed to give an even 50/50 weight distribution front-back axle. Not that this will necessarily make it 'agile', but it should be good for general comfort and stability dynamics. It is a significantly longer car than the Volt or Leaf, with bigger overhangs, - not that this necessarily means more space (the battery takes up some of that length, rather than being 'under' the occupant space) but it would mean a slower and 'bigger car' type of suspension experience. That suits me down to the ground, because I just like quiet, gentle plodding. My high-speed antics are a good and over part of my youth (now I recognise how much that actually costs, both financially and safety)! The Fluence is the heaviest EV I know of - of course the Volt is heavier because it is carrying around an extra engine, but likewise it can put down both the motor and the engine's power. So overall, the Fluence will be slowest!
Remarkably, for such a large car, I'm lead to believe the Fluence's aerodynamics are actually better than the Volt and Leaf. It has a CDx figure of 0.67m^2, which appears to translate into a Cd of 0.26 (cf. Leaf 0.29, Volt 0.28, Prius 0.25). The smaller Renault Zoe EV, just released, has a CDx of 0.75m^2!
So, aerodynamically, it seems fairly clear that putting the battery within the length of the vehicle, rather than underneath it (thus raising the height of the vehicle), is a good thing. But overall, for relative weight it makes the car heavier (if simply because of the extra length of the chassis), which is generally a bigger disadvantage overall than the aerodynamics are a benefit.
Last edited by
chrismb on Thu Jul 18, 2013 12:51 am, edited 1 time in total.