All those S's and C's...
...it's too much for me.
Bit like the current flowing through that 110V socket - too much.
Shelby Super Cars has announced details of the Ultimate Aero EV, the 'leccy brother to its $620,000, 1287bhp, 257mph production car world speed record holder. SSC reckons the Aero EV will be the fastest electric car ever when it hits the road later this year. The Aero will be driven by SSC's electric powertrain package called …
"Shelby Super Cars has announced details of the Ultimate Aero EV, the 'leccy brother to its $620,000, 1287bhp, 257mph production car world speed record holder.:
Guessing that the 'leccy version will be in the same price neighbourhood leads me to believe that I won't be affording one in this lifetime.
I can't see buying any battery car if it's going to cost 10k-20k more than the petrol version, have less mileage capability, most likely NOT last as long (I mean, seriously, how long does ANY car battery last?). Yessir, another toy for the rich and famous...
Guessin that it'll need a battery energy capacity of at least 30KWH to give 150 miles of endurance (for a head-shaped figure, one gallon of petrol contains ~9KWH of energy). Charging in 10 mins therefore requires more than 180KW of power, a current of over 1600Amps at 110V. This is beyond the capacity of household power supplies; a copper busbar witha cross section of around 1200mm would be required required to carry that sort of current.
Shelby is mostly known for slapping a huge engine into small light things and it going like hell. Ok, he is a kinda "genius". But if all the claims on this drive unit are true...300mph top speed, 1200hp equivalant, 200miles on a 10min charge...then yes, he is a genius, and he'll be tripping up over car companies lining up to license this thing.
Somehow though, I can't see it, and sadly it maybe time for someone to look more closely at checking him into an old folks home before he causes his company a few head aches. Until it happens, will say what Alun didn't...it's bollocks!
A bit of napkin math quickly proves this claim bogus. The standard US '110V' outlet is rated at 15A. Let's be generous and say we've actually got 124V on this (never seen one even close to 110V outside of a brownout.) That makes for 1860W. For 10 minutes, that's 310W/h, assuming they've managed a 100% efficient charger.
Now, a gallon (US) of petrol gives something around 33KW/h of potential. Let's assume that's going into an engine at 17% efficiency (no idea what the basis of that number is, it's just the I use.) That gives us 5610W/h of usable work.
Assuming these guys have perfected the 100% efficient motor to go with their 100% efficient charger (unlikely since it has water cooling) that gives us 1/18th the work of a gallon of gas. I don't care how efficient the running gear and aerodynamics are, you're not going to get 200miles out of 1/18th of a gallon of gas.
From their previous press release: "The drive train under development will feature a revolutionary power source allowing for extended time between charging intervals with the possibility of several years between charging."
http://www.shelbysupercars.com/news-071208.php
Read further down and it talks about new investors... reads too much like a scam in these cynical times!
10 minutes is "the time it typically takes to fill up a tank of gas"? My car's 53-litre tank typically fills in around a minute at my local Tesco, so we're talking about either an extraordinarily large fuel tank, a very slow fuel pump, or possibly a combination of the two.
Incidentally, if this "Nanotechnology Rechargeable Lithium Battery pack" can power a 200bhp car for 150-200 miles on a 10-minute charge, I want one for my laptop. I'd probably never have to worry about charging it for the rest of its useful life :-)
Paris, because it might take 10 minutes to fill her tank.
Thats a maximum charge of 275 Watt hours. To drive a car 150-200 miles you need 50,000 Watt hours or more. Unless your wall charger has it's own set of fast discharge cells that can charge for over 30 hours, and then dump that charge into the car in 10 minutes, then it isn't going to happen. Even in the UK, using 240v and a 30 Amp fixed feed, it would need a 7 hour charge.
Give up with all this battery nonsense and start rolling out Hydrogen fuelled based electric motor cars - the one of Top Gear the other week was perfect for the needs of today, clean abundant power supply, similar to less costs of a current motor and fills up at a petrol (or hydrogen in this case) station the same way a regular car does at again similar costs (now, so when being massed produced economies of scale should make that quite a bit less).
100 bhp is about 75 kilowatts, and if your battery can deliver that sort of power then you can probably make a car round it.
To have a range of 200 miles, a full charge must be able to power the car for long enough to actually travel 200 miles at reasonable speed. Let's call that 5 hours, or 300 minutes.
So the claim is that charging up can be done at 30 times the speed of running down.
That means your expecting to deliver roughly 2.25 megawatts through that 110 volt supply, which is about 1000 times more welly than a domestic socket.
If we're talking about driving 200 miles and charging for 10 minutes before the next
200 miles, that's a tough problem to solve:
Assume 50 mph and 20HP and PERFECT energy conversion (just for sake of argument)
that is: we're only asking 20HP out of the engine to maintain 50mph.
(200 miles / 50 mph) * 20HP * 0.7KW/HP = 56 KW-hrs * 60KW-min/KW-hr = 3360 KW-minutes
That's how much energy we would spend in a 100% efficient conversion.
Now let's replenish the energy store in 10 minutes: 3360 KW-minutes / 10 minutes = 336 KW
from the charging source.
At 110V that's 3KAmps.
That's an interesting number ;) Note that if it only took 2HP to drive us at 50mph, we'd still
be looking at 300 amps at 110V.
'SSC's "Charge on the RunTM" onboard charging system allows for 10 minute full battery recharges on a 220V service''
'Charge on the Run'? .... err sorry "TM"...
Does that mean it's got an ordinary petrol engine too or that you have to drive the thing with a dirty great umbilical cord plugged in to the 'lecy socket back on the ranch?
I smell environmentally friendly flower feeder...
It is perfectly possible to do a quick charge if the socket you're using can handle the amperage required. Most standard household sockets are only rated for 13A (UK) 15/20A (North American)
However a standard 32A socket could easily do a quick charge. and it isn't expensive to have one fitted.
...from the Delorean in the "Back to the Future" movies.
10 minutes on a standard electrical outlet wouldn't even provide enough charge to run a decent sound system for 200 miles at highway speeds. (well maybe at 257 miles an hour it would)
Lots of numbers being thrown around here, all assuming either the US or UK standard household plug. Be that as it may, it's possible they are also talking about a specific distribution model, a type of fueling station that is able to deliver industial levels of power through a "hose" to your "tank." Light on detail the press release is... but with the right equipment, it's probably possible to push a large amount of current through to a battery that is designed for maximum surface area to cut down on charge time. Now, whether the technology is actually there, doesn't cost as much as a house, and is reliable, that's a whole other matter. It's nice to dream, though.... and I tend to err on the side of dreaming big and seeing what can be done rather than focusing on what can't be done. Remember, it wasn't more than 50 years ago that the idea of a computer thousands of times more powerful than what they had then in a package that fit in a small box would have seemed ludicrous.
"Give up with all this battery nonsense and start rolling out Hydrogen fuelled based electric motor cars ... and fills up at a petrol (or hydrogen in this case) station"
I guess you have an aitch-two station in your area and everywhere else you want to drive? Also, perhaps you've invented a new energy efficient and non greenhouse gas producing method of producing hydrogen which is also cheaper than gasoline or electricity? Oh, you'll also a volume efficient way of storing the aicht-two on board the vehicle so as to giveit a range equal to current gasoline powered cars and still have some amount of trunk space.
'Cause those are the obstacles still preventing fuel-cell based cars from being produced.
The calculations here are making assumptions that no new technology is involved. It's like a car company talking about 500 BHP and people talking about how difficult it would be to tie 500 horses (British horses, mind you) to the front of the car.
There are a couple of ways of doing this that come to mind.
1. Electricity could be the secondary source of power. The car would potentially be using very little of electricity for driving purposes, maybe only for headlights and for controlling the primary source of power which could be a new invention. Then it wouldn't be classified as an electric car I guess, so this option is unlikely.
2. The initial charge could potentially take several hours or days, and then the 10-minute charges would simply "top up" the batteries. There could be a functional reason for not being able to use the car for more than 200 miles without such a recharge, or "200 miles" could be a number being quoted just for helping the potential buyers compare these against current cars.
GO - because the reliance on gas is a bad idea.
@Sampler
Hydrogen is not and will never be more than a way for car companies and politicians to show off and pretend they're "green". The reason it isn't feasible is because free hydrogen is rare and has to be captured from somewhere. The easiest source is natural gas. Producing hydrogen from natural gas also produces carbon dioxode, which is what we're trying to eliminate, and it doesn't break our dependence on fossil fuels. The other way to get hydrogen is to reduce water through electrolysis, but you end up putting more electricity into the process than you would get from it through re-oxidizing your hydrogen in a fuel cell. You'd have to have some sort of magical entropy-defying perpetual motion machine to endlessly produce free hydrogen to take advantage of it.
"onboard charging system allows for 10 minute full battery recharges"
If you re-read that as "a full battery takes 10 minutes to recharge" that makes more sense... also pointless, but they're american.
As for the huge currents involved, imagine how hot the cables would get - there's a reason the national grid uses very high voltage and thus lower current!
And all those calculating the power/range/current/etc... You seem to be assuming that all the automotive energy is coming from that charge; in reality it probably charges the batteries under braking/coasting, so you can probably halve your charge current.
Still smells remarkably like the male equivalent of a cow pat.
"fr far nesses sake is there anyboady who thinks the charging times qouted here can be done?"
Probably. To save you the effort of scrolling, my debunking calculation reckons the claims of the article are off by 2-3 orders of magnitude, but that is based on the remarks in the article about a standard 110v supply.
There's nothing to stop filling stations having access to much higher voltages. (For safety's sake, the battery would have to be removed from the car and sent through a completely automated charging system. Having lifted it out, you'd probably be as well to drop back in a different battery that you'd charged earlier, but let's assume there are legal objections to that idea.) At 11000 volts (available at a substation near you, albeit in AC form rather than DC), the required current is just a few dozen amps.
As someone else observed, however, unless the charging process is 100% efficient, some proportion of the total energy transferred is going to be emitted as heat. You don't need to do the maths here; that's equivalent to saying that some proportion of the heat generated by setting fire to a full tank of petrol will be released over the charging period. If that charging period is just 10 minutes, you probably wouldn't want to stand too close to the equipment. But again, if the charging process happens inside a fully enclosed robot, it can use whatever cooling mechanism it likes.
So, in conclusion, just lift your industry standard battery out of the car, drop it into a liquid nitrogen cooled 11000 volt concrete bunker (did I mention the risk of explosion?) and Bob's your uncle.
Is it possible to put 200 miles of charge into a vehicle in 10 minutes, using an industrial grade supply? Let's start with the assumption of a 50KW/hr battery (the Tesla has a 53KW/hr unit, and runs for an official 244 miles on a charge so it's a reasonable starting point). That converts to 50,000 x 60 x 60 = 180M Watt seconds. That amount of energy needs to be delivered in 600 second, so thats a charge rate of 300,000 Watts/second. Now there's very little chance that the battery pack is going to be anything as wimpy as 110v, lets bump it up to the same voltage levels that they use to drive electric trains, 750v. 300,000/750 = 400 amps. Add 10% to allow for inefficiencies in charging and we get 440 amps. That's a hefty but do-able number, and it's still less than $10 for a charge at US residential rates.
They're obviously editing the website.
Yesterday evening, it said
"SSC's "Charge on the RunTM" onboard charging system allows for 10 minute full battery recharges on a 220 outlet."
Now it says
"SSC's "Charge on the RunTM" onboard charging system allows for 10 minute full battery recharges on a 220V service."
So I guess it probably did say "standard 110V outlet" when Alun Taylor wrote the original article
I wonder when they'll change it to "industrial 3-phase outlet - slower domestic chargers also available"?
"fr far nesses sake is there anyboady who thinks the charging times qouted here can be done?"
To be entirely fair about the response I just gave, although it probably *can* be done, it would be very stupid to do it that way. Much better is to use the standard mains supply and plug your car into it overnight. Ten hours, rather than ten minutes, reduces the other numbers by a factor of 60, at which point the equipment is quite feasible. (Still, you'd want to locate it inside a locked garage. That would be a problem for many. Perhaps it is time to review the nation's housing stock.)
A nationwide network of fast charging stations would represent a huge capital outlay by car manufacturers. In contrast, domestic recharging would be a very small capital outlay by the person who bought the car. I think the latter is vastly more likely.
Very few people go on journeys that require more than one tank of petrol before they reach their destination. I'm assuming that hotels would have such equipment and that friends and relatives who were putting you up would be willing to let you use your equipment. It would be trivial for the equipment itself to state clearly how much energy it had delivered, so you could settle up afterwards.
And finally, transport apparently represents about 40% of the nation's carbon footprint, which is more than electricity generation. Domestic charging would represent a huge business opportunity for electricity generation and distribution companies, and with only a modest amount of "smarts" built into the domestic units the power companies could use them to smooth out the baseline load. The power company would broadcast a preference for "up" or "down" and the millions of chargers would respond. I'll let someone else work out the PID constants, but I'd be surprised if the diurnal variation couldn't be smoothed out entirely. The spikes around Eastenders finishing time would be harder, though they could certainly be made more manageable. That's good news for anyone who isn't running a gas-fired power station. (Note for foreign readers, I gather that's more a problem in the UK than elsewhere -- the size of the spike that is, not Eastenders, which presumably blights large parts of the globe.)
So yes, it is all perfectly feasible and will probably happen, but probably not exactly as described in the article.
Before anyone gets carried away over the specification for the Shelby Supercar, let's put some numbers to the claims. My car (Honda Civic IMA Hybrid) achieves about 50 mpg (UK gallons) and therefore, consumes energy at the rate of 65 kW.h/100 km, assuming the engine and transmission are 25% efficient, that's about 16 kW.h/100 km at the drive wheels. To travel 200 miles (320 km) it will consume 52 kW.h at the drive wheels.
If the supercar can match this mileage, the batteries will need to take on 58 kW.h (assuming the electric motors and batteries are about 90% efficient) in 10 minutes, which is charging rate of 350 kW. With a UK domestice supply at 230V single phase, the current required is just over 1,500 A. Quite a bit higher than any domestic supply I know of.
If a 3-phase supply is used, the current reduces to 500 A. Which is a medium sized industrial supply. For the technically minded I have assumed the power factor is unity, it will probably be less than 0.9 and the current (but not the power) will increse proportionately.
On this basis Shelby Super Cars are talk through their tailpipes and any charging system would require a major industrial installation.
As with most claims about alternative energy sources, the claimants are more interested in attracting publicity than putting down the facts.
It's an unfortunate fact that petrol is a very compact energy source and replacing it with something else is going to be very very difficult.
MORE Electric Car bollocks...
Am I the only one around here who's getting fed up with it?
These Electric Con-men have set up on gullible venture capital and now the VC tossers need some sort of return on their 'investment' - personally I'd sooner invest in a chocolate kettle manufacturer than an Electric Con-man - all these guys can think to do now is scam a bit more cash by making wildly improbable claims. Before they disappear.
Want to lay money on any of these 'hi-performance, quick recharge' BS artists being in 'business' in a couple of years? Anyone? Surely someone...?
Oh ye of little faith!
The 'A123' and similar 'safe lithium' cells can be recharged very quickly, somewhere in the region of 10-15 minutes, assuming you can get the power into them.
The issues with recharging a car in 10 minutes include not only having a good connection to the mains supply for the building where the car is charged, but also having a feasibly thin cable going to the car.
I assume no-one's thinking of a plug-in home charger using ultracapacitors to charge up slowly from the mains and then release all the power in 10 minutes (to avoid needing a powerful mains connection). Since the energy density of supercapacitors (Wh/kg) is many times lower than batteries, the charger would have to be many times heavier+larger than the car's battery pack.
In any case, what's the big deal with having a 10 minute charger working off a conventional outlet? Who actually needs that?
If there were recharging stations which were the equivalent of petrol (gas) stations, they could easily have large connections to the power grid.
On the other hand, a home charger is typically going to be used overnight, particularly as it would make a great deal of sense to charge vehicles overnight if possible, when electricity is typically cheaper due to lower demand.
@Stephen Hunter
"I guess you have an aitch-two station in your area and everywhere else you want to drive? Also, perhaps you've invented a new energy efficient and non greenhouse gas producing method of producing hydrogen which is also cheaper than gasoline or electricity? Oh, you'll also a volume efficient way of storing the aicht-two on board the vehicle so as to give it a range equal to current gasoline powered cars and still have some amount of trunk space.
'Cause those are the obstacles still preventing fuel-cell based cars from being produced."
So no obstacles, then? Because none of those are obstacles to a car being PRODUCED. They might be obstacles to it gaining rapid market penetration, but that's a different matter.
Incidentally, gasoline or electricity vary so much in price that you can hardly claim that hydrogen has to be cheaper than either before we can start producing. And since global warming is a lie, greenhouse gas concern is a bit overrated...