On May 14, 2015, at 6:35 AM, EVDL Administrator via EV <ev@lists.evdl.org> wrote:
> On 13 May 2015 at 10:58, Ben Goren via EV wrote: > >> 15 kWh / 15 minutes is 60 kilowatts...not quite the level of >> insanity of a megawatt, but still in a range far beyond what you'd ever see >> in >> a residential setting. > > Not so far beyond at all. A typical US suburban tract home has a 200 amp, > 240 volt service. If devoted entirely to an EV such an electrical service > could charge an EV at a continuous rate of over 38kW. > > Many modern "mcmansions," which are often built by the dozens in high end > developments, now have 400 amp service. This would allow for a continous > power of almost 77kW. > > Thus I'd say that the electrical infrastructure for 60kW charging is fairly > widely available right now. Er...no. Indeed, I think you just proved my point. 60kW is over half again as much as you get at the meter in most homes, and nearly 80% of what you get at the meter in a McMansion. How many people living in McMansions are going to be happy shutting down basically everything, especially all the air conditioning and pool equipment they paid so much extra to get the 400A service for in the first place, every time they want to charge the car? Worse...I don't think I've ever seen anything bigger than a 220V / 50A breaker in a residential panel -- though, granted, I'm certainly not an electrician. That's 11 kW. You're going to need half a dozen of those, almost as many as will physically fit in a typical panel...and just the cost of the copper for the wiring is going to be insane -- especially since the meter is, as often as not, on the opposite side of the house as the garage. And the cost of retrofitting a neighborhood for 400A...it'd be cheaper to cover all the rooftops in solar panels, add a bunch of batteries, and cut the grid connection entirely. I just don't see it. What I expect to see is, especially when 200+ mile ranges become the "new normal," for most people to do almost all their charging on a 110V / 15A (or maybe 30A, since that's not uncommon in garages) circuit, the types of people who buy the top trim level packages to get L2 chargers installed, and then a footnote for some sort of on-the-road rapid charging that only gets used out on road trips or out of desperation. And I expect to see those roadside charging stations struggle for profitability at the same time they charge exorbitant fees.... b& -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 801 bytes Desc: Message signed with OpenPGP using GPGMail URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150514/b1dca03f/attachment.pgp> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
