EEStor and Zenn cannae break the laws of physics

Auto-IT keeps hearing odd things about US startup the Zenn car company and its exclusive deal with ultrasecretive ultracapacitor startup EEStor [PDF]. An ultracapicitor, for the uninitiated, is like a big battery but it stores energy as a static electric field, rather than through a chemical process. You can think of it as a bag into which you can shove electrons, keep them there for as long as you want (given a little leakage), and get them out again as rapidly as you like (with much less waste-heat-generating internal resistance than a battery).

According to more than one enthusiastic report, the combination of these two inventive companies will result in a car that can travel 200-300 miles on just a five-minute charge. Real soon now.

Auto IT is here to tell you that, whatever technology lurks inside the eventual EEStor-powered Zenn, it will not be charging itself up in five minutes.

The problem lies with the nature of electricity.

Let’s be ultra-generous and assume that the EEStor and Zenn combination will be lots more efficient than the G-Wiz and will squeeze 200 miles out of the same amount of stored energy that takes the G-Wiz just 40 odd miles: 10kwh. This is not really feasible, but it is being very kind to the two plucky startups. It might just be possible if you drive veeeeerrrrrrry sloooooooooowly.

Anyway, to get 10,000 watt-hours into the battery in five minutes you need to feed in at a rate of 120,000 watts. This is just basic maths. You can imagine this quite simply: it’s like plugging in 120 single-bar electric fires and switching them on at once. As you might imagine, this will likely blow the odd fuse in your house.

Put another way, to supply this from a domestic UK 240 volt supply, you will need to charge at 500 amps. The maximum you can get out of one three pin socket is 13 amps, so you will need to plug your Zenn into about 40 sockets at the same time to avoid blowing any plug fuses.

Assuming you have 40 spare sockets, and the patience to plug them in, you’ll immediately blow the main fuse. Domestic electricity supplies just aren’t built to supply 500 amps.

So will you instead charge your Zenn at a sort of electric petrol station? No. First, there are none. Second, a 500-amp cable would need to be roughly 40 times as heavy and stiff as a domestic kettle’s cord. Unless you pump iron every day, you’ll find it difficult to plug in.

No, it’s much better to charge an electric car over a period of hours, during the part of the day when it’s not moving (given that nobody – barring a few madmen at Le Mans – drives for 24 hours a day).

Instead of charging over five minutes, charge for 40 times as long – at least 3 hours and 20 minutes – and you can use a normal three pin plug.

That’s the future of electric cars, no matter what. Unless you use a fuel plus generator or fuel cell to make electricity on the spot, electric cars are going to take hours to charge. No breakthrough in battery-style storage is ever going to change that. It’s just maths.

The hub of the problem

Time was when you’d whack the middle of the steering wheel and you’d hear a faint peeping from under the bonnet. These days wheels aren't made of Bakelite and horns have got a lot louder, but the horn button has typically migrated to the end of a stalk to make way for an airbag.

Now it seems that carmakers have other ideas for this piece of automotive furniture that stares us in the face whenever we drive.

Citroen caused a stir by making the centre of its steering wheel sit still. The large central boss of the wheel in the C4 is fixed, while the wheel and its spokes whirl around a hub hidden behind the boss.

Why? According to the French firm, this arrangement allows the fitment of a better airbag. Since the orientation of the bag is known, it can be shaped and sized to more efficiently cradle your hurtling bonce during an impact. Basically, it doesn’t have to work when it’s been spun upside down.

But if Toyota’s stand at the recent Geneva motor show is anything to go by, Citroen’s cleverness is just the start. Toyota clearly thinks the hub is a great place for putting driver information systems.

The Hybrid X concept car features three bits of user-interface real estate: one big screen in the centre console, one curvy console where the conventional instrument panel belongs, and a third information screen slap bang in the middle of the circular thing you steer with.

Meanwhile the FT-HS does away with the middle bit of the steering wheel altogether. Instead the rim of the wheel rotates while the spokes stay still (which kind of implies steer-by-wire – yelp). This allows a shaped airbag and a clear view of the instruments on the far side of the wheel.

Now Auto IT may be thicker than a Hummer omelette, but is all this cleverness truly necessary. After all, unless you’ve got gibbon’s arms, the centre of the wheel tends to be comfortable sited when it’s well below the driver’s line of sight. Which means that the best place for up to the minute info isn’t way down in the wheel, but up there on top of the dash – even floating at the foot of the windscreen in head-up display format.

Our money is on hubs staying put for the foreseeable future.

T3 - three wheels and CC exempt

Now that the London Congestion Charging zone has expanded westward, the search for ways to avoid coughing up £8 for slipping a tyre into the controlled zone has intensified. Auto IT has finally spotted a vehicle that fits the motor tricycle exemption from the charge (see the earlier post Will the congestion charge make you go Ape? for details) .

You don’t have to pay if your “car” has three wheels and is less than a metre wide and less than two metres long, a peculiar exemption that seemed to fit no vehicles at all.

Well it does fit the T3 Series of patrol trikes from T3 Motion. These look a bit like a Segway Human Transporter without the stupid/clever self-balancing complication - instead the T3 relies on a tried and test, old-fashioned third wheel instead of gyroscopic silliness.

A T3 uses a pair of lithium-ion batteries to give a maximum quoted range of 75 miles and a maximum speed of 25 mph (probably not both at the same time, mind). Plus, because it is aimed at security workers, it has a siren and flashing strobe lights to help encourage people to get out the of the way while you’re commuting.

The snag? Well, it costs about $6,200 (£3,200) for the trike plus $1,800 (£930) for the long-range batteries. Plus you get wet when it rains. And you may get the odd stare.

Ready to race?

The GT40 racing stripes and door numbers on this G-Wiz, spotted in Central London, are presumably knowing and ironic. Unless there is a one-make racing series out there that Auto-IT is blissfully unaware of? Given that the battery powered car takes 2.5 hours to charge to 80% capacity, and eight long hours for a full charge, one thing is certain: G-Wiz racing is never going to feature frantic, against-the-clock pit-stops.

Filed under cars and green

G-Wiz: nought to sexy and back again in 5.6 seconds

Good celebrity product endorsement moment: having cool, elegant, sexy actress Kristin Scott Thomas appear on the BBC’s popular Top Gear programme and inform the watching millions that she drives a Reva G-Wiz whenever she’s in London.

Bad celebrity product endorsement moment: having cool, elegant, sexy actress Kristin Scott Thomas go on to tell the watching millions that when it’s dark and it’s raining and you’re driving a Reva G-Wiz, you can have headlights or windscreen wipers but not both.