Day 4: Winds of Change

Day 4 of the #TeslaElectricStartupSuperTrip dawned clear and cool.  Temperature was 50 F to start the day with steady winds at 20 mph out of the north-northwest, gusting up to 35-50 mph.  These conditions were clearly out of the ordinary even for the windswept US plains as Weather Underground had a Wind Advisory in effect from 10 am to 4 pm. 

This was our first day of real sightseeing for a change.  Our plan was to stop at a number of the National Parks and monuments in the area.  Our tight trip timings meant that we only made a short trip at the Minuteman Missile National Historic Site visitor center and didn’t have time to take the 10 am tour of the Launch Control Facility.  So we made a short detour back on I-90 to check out the Delta-09 Missileman site.  There wasn’t much to see there but it did give us valuable information on our energy consumption traveling against and with the wind.

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As mentioned previously, the most important variable regarding Tesla energy consumption is the effective airspeed.  With this 20 mph headwind going straight against us, traveling at 65 mph was effectively the same as driving 85-100 mph in still air but without the much better forward progress of that speed.  The impact was most noticeable on this short 4 mile detour south-southeast on I-90 to visit the Delta-09 Minuteman missile site. 

While we had been using somewhere in the neighborhood of 450 Wh/mi driving at 65 mph north-northwest to start the morning, we used less than 290 Wh/mi for that short stretch.  Even with these estimated values, that’s clearly more than a 50% difference between those values, which can mean the difference between getting to the next SuperCharger and calling a tow truck.  I’m really glad that we had topped up the battery for the 12 hours overnight at the hotel as that 45 miles of Rated Range gave us the cushion we needed in this stiff headwind.

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We arrived at Badlands National Park as the wind was still picking up.  We decided to drive the Badlands Loop Road, the main road through the park.  Being the brave souls that we are, we took a couple short walks to The Window and The Door, two viewpoints into the Badlands.  Even with the wooly hat and gloves you see me wearing in the photo (and the thermal layers you don’t see), I was quite cold.  Between our schedule and the wind, we only did one more walk (hike would be too strong a word) on the Cliff Shelf Nature Trail (see photo below), made a short stop at the visitor center, and continued on our way.

Badlands National Park: Cliff Shelf Nature Trail (South Dakota)

Techno-geek time again—LJ has been tracking this trip using a GoPro Hero 2 mounted on the inside of the front windshield.  He started the trip with a 30-second interval between photos and reduced it down to 10 seconds for this national parks part of the trip.  There was a slight malfunction that means we didn’t catch the first photos of this day but we got it sorted out.  Once LJ gets them pulled into a neat timelapse movie, I’ll post some links here.

Our SuperCharger lunch stop in Rapid City was next to the Rushmore Mall.  After ~45 minutes charging while having a Subway lunch and a Starbucks coffee, we were back on the road around 1:30 pm.  The first post-lunch stop was Mount Rushmore National Memorial, where we paid the $11 parking fee so that we could go see the mountain.  The amazing granite walkway up to the memorial combined with the almost complete lack of tourists made it feel almost like we were trespassing.  We were able to find another couple with an SLR (Nikon, not Canon, but they still understand how it works) to take the photo below. 

In front of Mount Rushmore, Black Hills, South Dakota

 

After our short stop at Mount Rushmore, we headed to the Crazy Horse Memorial, a place that I had never heard of before a random conversation at a friend’s birthday party less than a month ago.  I’m so glad that I had that conversation as this memorial was a pretty amazing place.  We had one of our more entertaining Tesla encounters when we drove up to the guard gate for the memorial.  The Native American guard first asked, “Is this thing running?”  to which LJ replied in the positive.  In the next couple minutes, we got to the question, “Is this a Prius?”  LJ told him a bit about the Tesla and we were on our way in.

The photo below does not do the memorial justice.  As noted in the site brochure and on the website FAQ, all four heads on Mount Rushmore would fit inside the head of Crazy Horse, which is all that’s been finished of this monument so far.  It took them 50 years to complete the head (from 1948-1998)—I’ll be interested to see what they can finish in the next 50.  Since this post is getting a bit long, I’ll capture the rest of the day in a part 2 post.

Crazy Horse Memorial in the Black Hills of South Dakota