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Comment by gnaffle | Hacker News Reader

"I still think computers will not succeed. They have been built since the 50s, and the price tag, the space they take, the heat and energy consumption have always been a problem."

I think you fail to realize where electric cars are on its technological trajectory. They're still in its infancy, and it's not like there's no more innovation to be had in battery technology etc.

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I do realize this. But I was talking about the Tesla in its current form.

Ofcourse it might get a success some day. Maybe we won't have to charge them because they all will have a small nuclear reactor.

My point is: a lot of people are still thinking 300 miles on one battery charge is not enough. And maybe this is true when you go on holiday or something. But most of the time people are fine driving an electric car from home to work and back.

The current Tesla will succeed if there are enough people that want to, and have enough money to buy a high performance electric car. It's not so relevant what most people think about electric cars if you don't target the mass market. Most people that can afford a Tesla will probably afford another car to go on holidays (or they will be enthusiastic enough about their Tesla to plan their holidays around charging stations..)

Tesla at this moment in time is not a car company that is marketing its product to the average consumer. They realize the technology is currently not their, but their go to market strategy is to market their luxury product to people who can afford a $50k car. At this point it is not about the worry of charging or where. My assumption is that the vast majority of people who own Tesla cars have a charging station in their home and understand the limits of the product.

They purchase the car for status, just like every other luxury product.

300 miles become irrelevant when you can recharge your car in 5-10 minutes, and that is where the technology is going.

Charging a 300mile electric car in 5-10 minutes is not going to happen any time soon, and it's not because of battery technology:

The model S uses 85kWh to go 300 miles (at 55 mph, remember which is way slower than you'll go on the freeway in California). 10 minutes is 1/6 of an hour so:

85kWh * 6/h = 510kW. Do you really think we are going to have 1/2 MW charging cables? Obviously this is not going to happen with home charging. Can you think of a way of even getting 1/2MW to a commercial charging station in a populated area? What about on e.g. labor day when large numbers of people want demand. If 10 people want to do a 10 minute charge in the same city at the same time, thats 10MW, which is a lot of coal we are burning to supply that (or if you want green power, about 100 acres of photovoltaics)[1].

I'm all for electrics, but I know the power grid is going to need an overhaul if more than about 1/8 the population adopts them, and on top of that current trends indicate that most of the new capacity is going to come from coal plants, which largely negates the environmental advantages of electrics.

1: http://en.wikipedia.org/wiki/Nellis_Solar_Power_Plant

I'm not very experienced in electronics, but couldn't you constantly store the source electricity in some sort of storage (battery, capacitors) and then dump it quickly into cars? This may not be feasible due to the efficiencies or safety factors involved, but the car wouldn't necessarily have to draw directly from the source line. The recharging stations could draw line power to recharge their storage overnight while the use of their charging terminals is low. However, I imagine the storage would be extremely pricey for the home market.

The most economical way of storing electrical energy on-site is probably the lead-acid battery. Enough lead-acid batteries to store 100 car recharges would be 1200 cubic meters. I found estimates from $0.17 to $0.50 per watt hour which would put the cost at over $1M to handle 100 car recharges. Charging that up continuously would put the energy requirements at 440kW assuming 80% round-trip efficiency.

Thanks for the numbers. It looks like we still need plenty of breakthroughs or drastic shifts in society for this to be realistic.

> 1/2 MW charging cables

Cables are rated by the current they support, not by the power of the devices connected to it. A cable up to 10 Ampères supports 1100 watts on a 110V mains, or 2200W on a 220V mains. Quick charging on electric vehicles probably is done at high voltages.

http://en.wikipedia.org/wiki/Ampacity

EDIT: you are right about home charging not possible. And to the sibling, the best storage systems for fast charging are http://en.wikipedia.org/w/Supercapacitor and http://en.wikipedia.org/wiki/Flywheel_energy_storage

Funny, when I looked at the specs, I thought 160 miles on a charge was more than enough for me. I think a tesla, or electric car in general, fits nicely into the second car of a two-car family model. Now we just need more renewable energy to power these things.

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