Re: 180Nm of torque – that translates to 65bhp and 133 lb/ft in old money
tl;dr - guys, if you're going to offer such a heavy car to the market - a good 150 to 200kg heavier than the petrol version - it needs stronger motors, and I don't mean ones with meaningless torque figures that only apply over a very limited speed range and only when compared against traditional cars with the same gearing. In REAL WORLD terms, this one struggles to come even close to the performance of the base 1-litre, which handles the 0-100 sprint in between 12 and 14.5 seconds depending on trim level... despite having barely half the peak torque output (!) and almost exactly the same bhp. 16 is a bit yesteryear, and pushing against the limits of what I'd call acceptable for everyday use; my old VW took 20, and that felt terribly slow at times... what's one that sits between that and my current "adequate" TDi going to feel like? And that's without considering what appears to be the electric equivalent of automatic transmission lag off the line - which is one of the reasons there even exists a petrol version that needs 14.5 seconds, because it's the auto and thus doesn't get the benefit of pre-revving and dumping the clutch for a faster start...
If electrics are going to be sold on the basis of being nippier, having instantaneous lung-collapsing acceleration and the like, it'd be nice if it was... yknow... true. Something with a 16-second 0-100k sprint time isn't cutting that mustard with me. That's the performance of an economy-tuned 1.2 litre supermini (or lower-end diesel, possibly not even a turbo one) of 10 to 25 years ago...
... aaaaaaaand there now follows an orphaned section where I tried working out the power and such before realising I was putting it in the wrong place. This is largely due to the small edit window and me having not pre-planned this alarmingly sprawling essay. The information may still be of use, it just didn't find a home up above.
Also I've just noticed that I misread the torque rpm as 2000 instead of "2490" somehow. Thus a quick correction to all posted figures, rounding that off to "2500" (which makes bugger all realworld difference).
Max torque speed at 10km/h per 1000 is thus 25km/h, or approx 15-16mph. Thus more disappointing still vs it kicking in at 10mph for the ICEs... we can only hope it rises in a fairly shallow curve from 0, or is indeed flat.
Power produced at that speed is therefore a rather healthier 63bhp, very nearly its entire peak power - which may well, therefore, hit at 65bhp plateau no later than 3000rpm (the brilliance of modern digital controllers, eh...).
Which actually is fairly astonishing (and makes you wonder just how bad the launch lag actually is, because a car which can maintain an average of at least 64/1.12 = 57hp/tonne from 25km/h on its way to 100km/h shouldn't be too sluggish at all... hell, that's better than what my DCi makes at its 2000rpm, 200Nm (= 56bhp) maximum and ~1080kg weight (= 52bhp/tonne, though that IS at about 11mph and it does eventually pull to 86bhp)) and really should be more what they're highlighting here. Yknow, "produces maximum rated output from as little as 18mph all the way to 70+mph", something like that, rather than the often rather meaningless torque figure. Still, it kinda fits with the acceleration. (Although it's not an accurate way of doing it, if we consider the petrol one has a PWR of about 75bhp/tonne and streaks to 100km/h in 12 seconds dead, (12.0/57) x 75 is only a hair off the electric's actual time. The leccy should come out a bit faster than that, given that the petrol probably doesn't achieve full power until at least 20-25mph, and will have to change gear at least twice along the way, so I can only presume that initial lag is at least equal to the generally needed rev-up time (seeing as the sprint time is a minimum, measured only from when the wheels start to turn)...
Right, errata over, onwards with further dumpage.
Now, as power is merely force multiplied by velocity - i.e. it's the ability to keep the wheels pushing against the road with the same relative oomph as the car travels faster, which is what torque ultimately provides (and why you accelerate less in higher gears, as the power is delivered as lesser torque/force but at a higher wheel rpm as the multiplication factor reduces ... and also why comparing ICEs to electrics is HARD) - it's possible to work out one from the other, so long as you have all of the necessary arguments. And in this case, even though we don't have the full details of the power curve, we do have the torque at a certain speed, and a reasonable stab at the gearing.
Power in bhp is equal to torque in lb.ft at 5252rpm. Thus, 133lb.ft at 2000rpm is an actually-fairly-respectable 50.6bhp. Producing that much power at 12-13mph isn't too shabby, especially from a 65bhp motor - and unlike an ICE which, unless it has a CVT, will have jumps in its gearing where the power falls back some as rpms drop (and may momentarily cut out altogether), it'll maintain at least that much on its way to its peak. Which is why it'll probably feel fairly thrusty once it does actually get going, even if it lacks a bit initially and at the top end.
However, this does mean that the maximum torque CAN'T be maintained anywhere higher than about 2560rpm (ie, 16mph), and that's if we assume it hits max power at that point, rather than it being the usual gradual slide from one to the other. That's a pretty narrow peak even by internal combustion standards. I mean, it'll still remain fairly strong for a while, even if max power isn't reached until right on the limiter (in this case, representing no more than 26lb.ft shaft output ... though that's still equivalent to holding the old VW in third gear all the way to 80, which is something I actually did a coupla three times on hilly motorways...) it only loses about 8% for every 1000rpm / 10km/h, which means it'll feel like it's being maintained much more continuously than in any given non-CVT ICE, but it does show we shouldn't get too hung up on a figure like that in this setting as it's actually kinda meaningless.
I'd be rather more impressed if they're just fronted up and said that it "produces more than 50bhp from 20km/h right up to 130km/h, with a peak of 65bhp at (1)xx km/h, with a starting thrust (at standard kerb weight) of yyyy Newtons". That'd let us put electrics on a more even playing field with each other, because from now on a motor's raw shaft torque will mean little when not processed with a mind towards its top speed, max rpm and weight. I mean, that's already the case anyway, but most everyday cars have roughly the same weight and starting gear, so it's a more fungible measure... It'll seem unfamiliar at first, but hey, we got used to euro cycle economy ratings, CO2 emissions and 0-100k acceleration stats... I'm sure we can deal.