THJ Media Blog

2019-09-22 e-Golf Drive SLO to Santa Rosa Posted on September 22, 2019 17:31:30.

e-Golf SLO to Santa Rosa
September 22, 2019

Left SLO with 31/32 capacity at 7:24 AM, 65 degrees, 20820 miles odometer reading. Drove the speed limit except between Paso Robles and King City and didn’t use air conditioning until after King City.

Fast charged in Paso Robles at Cool Hand Luke’s Steakhouse ChargePoint, 1111 Riverside Ave. 24 mi, 20849, 7:56 arrival, 35 mins to charge, started at 72%, ended full, no interruptions. Slower 25 kW charger. Got bagels and coffee at Oak Pass Cafe; dark roast was too bitter but decaf, latte, bagel and bagel sandwich were all good.

Hypermiled 100 miles between Paso Robles and Salinas to make sure we could stay above 20%. It’s 680’ downhill and there was no noticeable headwind, but just to be sure I drove 55 MPH to King City even in the 70 MPH section where there was almost no traffic so it was easy for the few cars to pass me. The slow chargers at King City at 615 Canal Street next to the decommissioned ChargePoint fast charger is 52 miles from Paso Robles, so we needed to be above 58% when we got to King City to skip using them; if we were below 58% we would need to charge the same amount above 58% assuming constant efficiency, but the wind speed could increase. But if we only used the slow charger to top up it wouldn’t add too much time. Say we came in at 48% so we had to charge to 68% or +20%, that would take about 1 hour at level 2 charge rate. But fortunately we arrived at 21/32 or 66% so we skipped it. The temp at 9:50 AM was only 79 degrees so not using air conditioning was OK. After King City the traffic picked up so I started driving the speed limit again to be safe. Arrived at Salinas fast charger at Nob Hill Foods EVGo, 1320 South Main St. at 10:44 AM with 34% capacity, ODO 20949. Took the Monterey Peninsula exit to get there. Note that this is higher than the 25% in the reverse direction 5 days earlier, but the other direction was started at 95% instead of 100% and was traveled at 65 MPH and was 680’ uphill so the latter two changes only made a 4% difference.

Determined that driving slowly does matter by setting the cruise control on a flat straight stretch, letting it stabilize, then writing down 10 instantaneous efficiency data points spaced 5-10 seconds apart:
55 PMH: 6.32 mi/kWh avg, 0.68 mi/kWh standard deviation, 226 mile range if driven steady from full with 35.8 kWh pack
60 MPH: 5.29 mi/kWh, 0.52 mi/kWh standard deviation, 189 mile range, 16% worse
65 MPH: 4.65 mi/kWh, 0.41 mi/kWh standard deviation, 166 mile range, 26% worse
70 MPH: 3.94 mi/kWh, 0.39 mi/kWh standard deviation, 141 mile range, 37% worse
Granted this is fraught with error such as slope and wind speed and accelerations make a big difference, so more study is prudent.

Fast charged at Milpitas Great Mall EVGo, 447 Great Mall Drive, 67 miles from Salinas, 12:42 PM 45% start, 98% end after 45 minutes. ODO 21016. Ate at Chipotle on the far side of the mall, took the whole 45 minutes to walk there and the restrooms and back. Lots of clothing stores.

Drove 97 miles home to Santa Rosa, arrived at ODO 21113 3:25 PM, 293 miles, 8:01 door to door vs. 4:30 hours minimum driving time at the speed limit with no traffic, but there was at least 0:40 of traffic slowdown at Gilroy, San Jose, Oakland and Novato, so with 2:05 charge time and 0:12 slower driving between Paso Robles and King City it probably would have taken 5:45 using gasoline stopping once for gas and bathroom and once for lunch. So we added about 2:15 to drive our 125 mile range EV. Worth every minute to me, given we did it without gasoline. I will prefer it in the future over gasoline if it is an optional trip such as going for a visit or seeing a show. We don’t need to rush. We kept ourselves busy eating and analyzing data, but we could bring books and computers and do homework or doodle or take a walk while charging.