Why large scale implementation of EV vehicles isn’t possible

Why large scale implementation of EV vehicles isn’t possible

The truck can drive 500 miles on a single charge, which was higher than some analysts had expected. That may mean that, in terms of range, the vehicle could meet the needs of long haul truck drivers. 

“There apparently were eight charging ports, and with a 100kw battery behind each that would be 800Kw.  To deliver 90% of capacity in 30 minutes you’d have to deliver approximately 1.5 Megawatts plus losses; batteries are 80-85% charge efficient during the bulk phase until they reach about 80% of capacity (at which point their efficiency goes down materially) and the electronics to control the charge have loss too — probably in the neighborhood of 10%.  So we have a 76%, more or less, efficiency on the charge rate which means we must deliver almost exactly 2 Megawatts to the truck for that 30 minutes.

I note that 500 kilowatts has to be dissipated somewhere for that entire period in the truck or the batteries, controller equipment or both catch on fire.  This is a serious problem all on its own that I am not convinced Musk can solve.

Then there is the economic issue.  Musk claims he’s going to “guarantee” a 7c/kwh price for all that power.  How he thinks he can do this in a commercial environment where demand meters are used by law is beyond me; the first time a trucker needs to be charged at 4:00 PM on a 95 degree day there will be a very large surprise delivered in the form of the bill.  Never mind that the trucker (or company) will be paying for the 25% losses too; you get to pay for the entire megawatt-hour even though you only keep 75% of it; the rest heats the air.  Apparently Musk thinks that he can simply build “battery packs” to store energy and thus charge them when the power is cheaper.  Ok, that’s fine and well, except (1) now you have another 25% loss, stacked (you take one when you charge the pack when “cheaper” and then when the truck is charged) and for each truck’s worth of capacity in said battery bank he gets to buy another battery that would otherwise go in the truck, plus another 25% to cover the losses when the truck is charged, plus the electronics to charge, discharge and control that “banked” pack.  Somehow this all is going to “work out” to 7 cents/kwh.

Let me make this clear: No it won’t.  If Tesla guarantees that rate to the buyer then Tesla will absorb billions in losses and the more trucks are on the road and the more miles they drive the more money the company loses.

But it pales beside what Musk claims to be able to do when it comes to charging these trucks in the first place.  The average house in the United States consumes about 12 megawatt/hours of energy over the entire year, or about a megawatt-hour per month.  Musk intends to suck twice as much energy from the electrical grid as your house consumes in a month in 30 minutes.

To put some perspective on this that means that one such truck charging will place approximately the same load on the grid as 1,400 houses.  One truck.

What happens when 20 of them show up at the truck stop?  You know they do that today — they fill their diesel tanks and they’re on their way, although they typically only fill said tanks half as often as these batteries will require charging.

So it won’t be 20 of them it will be 40 since their range-before-refueling is about half of common OTR trucks now.  Now we’re talking about the load of roughly 57,000 additional houses that will be instantly presented to the grid and which the grid must be able to support — per truck stop or terminal!

Who’s going to pay to build all that out and with what will they do so?”

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