Sunday, November 17, 2013

Is West Texas toying with Terry Hershner - stuck in the fog after finding a 100 amp charging station

This morning, Terry Hershner appears to still be stuck in West Texas.  When I went to bed last night he'd made it past El Paso, and was on the highway and looked like he'd make it to San Antonio or farther by morning.  This morning we see the report below, that they'd made it to the Iraan Energy House, where they have a Clipper Creek CS-100 that can provide 24 kilowatts burst charging power, and 16 kilowatts continuous, through one charging plug.  However, shortly after that he made another post about being stuck on the side of the road in thick fog.

Terry's traveling companion, Bun Bun, wrote this:
Trip update: visibility zilch (3-5 meters!)

Heavy fogs rolled through while recharging in Iraan... We've been traveling all night, but for about the last 50 miles we've been driving @30mph with deer throwing themselves at us!

West Texas appears to be playing with Terry?

It appears they've made it about halfway across, but they're close to the 2 day mark.  Once this fog burns off they'll be able to start rolling, and the charging stations are more plentiful as they head east.  Getting past West Texas is the big hurdle.  UPDATE: They just posted another link to a Glympse viewer, making it clear they're on the road again heading at 65ish miles/hr east from Ozona TX.  According to Google Maps it's 206 miles from there to San Antonio, so we should expect another stop for charging before that city.  Plugshare shows a KOA campground and that San Antonio is rich with charging stations. 

What Terry's overnight report reminds me of is the question in my mind - just how badly do "we" need "fast charging" anyway?

Some of the automakers appear to have been delaying electric car manufacturing plans to wait for fast charging standards to be fully tested and implemented.  Though, why didn't they just adopt CHAdeMO and get on with it is a mystery.

Anyway, the J1772 plug is spec'd to handle up to 19 kilowatts, which is 3x the charging rate that's common now (Leaf, Ford Focus Electric, etc).  For long trips like what Terry is doing, the charge rate effectively limits the speed of travel.  At 6 kilowatts the rule of thumb is you're gaining 20-25 miles of range per hour of charging.  So at 19 kilowatts it's more like 75 miles of range per hour of charging.  That's a pretty useful rate of charge.  With the 16 kilowatts continuous Terry says the CS-100 can handle, that's about 60 miles of range per hour of charging, still pretty useful.

Those figures are for cars - motorcycles require less energy than cars, so have a higher effective range gain per hour of charging.

If the car makers were to simply upgrade the on-board chargers to handle the full 19 kilowatts of the J1772 spec, electric cars would be that much more useful while not requiring expensive fast charger infrastructure.  The infrastructure would be more expensive than it is now, because 100+ amp circuits are more expensive to install than the 40 amp circuits required for a 6 kilowatt charging station.

The way things are positioned currently, the 6 kilowatt charging infrastructure is touted as "This is the Way Things Will Be" with nobody talking about upgrading level 2 charging above that power level.  That's leaving electric car owners stuck with 25ish miles of range gained per hour of charging.  And while that's much better than the 12ish miles of range per hour of 3 kilowatt charging, it's still not very fast.

For example, when I went to Craig Vetter's shop to visit with Terry and crew, I drove my electric car of course (because it's the only car I own).  The on-board charger is a Manzanita PFC-40 which can handle 8-9 kilowatts charging rate, but this is effectively limited by the rate supported by public charging infrastructure.  First, the voltage is typically 208 volts but sags to 205 volts during charging.  Second, the stations are configured for 32 amps max, and while the charger can handle 40 amps there's a risk of popping the circuit breaker if the charger is set above 32 amps.  That calculates out to 6 kilowatts or so.  The trip to Vetter's shop is 100 miles each way, and it took 4 hours of charging time each way, plus 1 1/2 hours driving time, making it 5 hours each way for a 100 mile trip.

What Terry has done to get around this limitation is to have multiple J1772 plugs and use multiple chargers.  If he stops at a charging station location with multiple charging stations, he can simultaneously charge from each station.  Two stations means 12 kilowatts, and three charging stations means 18 kilowatts.

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