Roadtrip!

Roadtrips can be one the best parts of EV ownership, but, to be honest, the first couple of trips might seem a little daunting, so this post will explore how to plan a successful trip.  There is no substitute for “doing”, so I would suggest you get a couple of short trips under your belt before planning a cross-country trek.  Start by planning a trip to a nearby Supercharger, then try a trip in the 2 hour range.  This will get you used to charging, using the various tools described here and developing a feel for how your driving style compares to the models the planning tools use.

 

Will I Get There?

The main concerns new owners tend to have is around running out of charge before getting to their destination.  The best way to reduce the odds of this happening is with data and planning–both before the trip and during the trip.  Luckily, there are a number of very good tools to help on this front.  Why do you have to use special planning tools and not just use Apple Maps, Google Maps, etc to plan your trip?  Two reasons:

  1. Regular map and navigation apps don’t include information that might impact your vehicle range, such as changes in elevation.  EV-specific modeling tools take these things into account
  2. Mapping apps usually lack info charging stations, so using a unified tool ends up being simpler and faster

Pre-Planning Tools

The first step in planning a trip is to get a general idea of the route and charging requirements. There are 4 tools I can recommend:

Tesla Trip Planner with Range Assurance

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The simplest approach is to simply plug your destination into the navigation in your vehicle.  If will churn out a route and a list of recommended charging stops.  The trip planner has the advantage of always being handy and it will make sure you get to your destination.  For trips of a couple of hours, its probably all you need. The biggest issue with the trip planner is that on longer trips, it may not take the most optimal route and it does not have visibility to non-Tesla chargers.  For example, for planning a trip to Bend, OR, there is about an hour difference in trip time between the route the Trip Planner picks and the route I take because, courtesy of PlugShare,  I know there is a 80A L2 charger along the way, which saves me a detour to the Supercharger.

EVTripPlanner.com

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Source: EVTripPlanner.com

EVTripPlanner.com is a much loved website that lets you do more fine-grained trip planning.  It produces the same type of route and charging info as the Tesla Trip Planner, but with access to a few more knobs to customize the modeling.  It also gives you some potentially useful statisitcs on total driving time and travel time.  Because you can access the site form the comfort of your couch, its also a better tool to do some “what if”-ing with alternate routes and non-Tesla chargers.

EV Trip Optimizer for Tesla (EVTO)

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Source: EVTO

EVTO is a new mobile app written by one of our very own club members.  Being the newest kid on the block, it has a number of useful features, and, like, EV Trip Planner, is a great tool for running “what-if” scenarios. It is available for Apple iOS and Google Android platforms.

A Better Route Planner (ABRP)

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ABRP is another new trip planning tool.  Its unique in that it lets you plan your trip at home and then follow-along in the car during your trip.  It has a solid set of planning options and offers Android integration.

PlugShare

Have you bookmarked Plugshare yet?  As part of your planning process, Plugshare is invaluable in finding non-Tesla chargers or chargers at or around your destination.

After your first couple of trips, you really only need to go through this planning step for new destinations or if you are going at a different time of year where, say, the weather might be a factor.  You only need to figure out how to get to Grandma’s house once.

Other Owners

Sometimes its helpful to get insight from local owners in an area you will be traveling.  Here are three three ways to get connected with owners in other areas:

In-Trip Tools

Once you have created a trip plan, you need  to make sure you are tracking to your plan during your trip.  All these planning tools make assumptions on how you will drive and you need to be able to track how you are actually doing. Luckily, you car gives you most of the information your need.

Tesla Energy App

The buiilt-in Tesla Energy App gives you most of the info you need to complete your trip with confidence.

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For trip purposes, open up the app and go to the “Consumption” tab and set the app to “30 mile” and “Average Range.”  The finely dotted line represents efficiency used to model the remaining rated range displayed on the dash.  The thing you want to pay attention to is the coarsely dotted line which represents your average efficiency over the last 30 miles.  As long as your average stays above the rated range line, you will have at least as much range as displayed on your dash.  I tend to ignore the “Projected” box as it can vary widely and cause some unnecessary stress.

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If you have a destination plugged into the navigation, you will also gain access to the “Trip” tab in the energy app.  The Trip tab gives you a simple chart that shows the modeled decrease in charge from your current location to the destination or next charging stop.  As you drive, the colored line will show actual usage and a grey line will continue to show the original projected usage. If the “actual” line tracks below the grey line, you are consuming the battery faster than expected.  As the battery depletes the line will change colors using the same scheme as the battery icon on the dash: at 20% left it will turn yellow and at 10% left it will turn red.  The line will turn black at the point the car believes you will run out of range.

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Mobile Apps

  • If you are using EVTO you can check it during your charging stops to see how you are doing
  • Waze or similar traffic apps are useful to get a look at the road ahead to see if there are accidents or road closures that you might want to avoid and to make sure you have enough range to accommodate any detours.
  • Yes, one more plug for Plugshare to help you find chargers in a pinch

Charging Strategy

The biggest change when traveling with an EV is that it does not always make sense to fill the tank.  When driving a normal car, filling the tank at each stop is automatic; however, because of the “taper” when using Superchargers, its not an effective use of time to charge to 100% every time you stop.  In reality, it takes less time to fill the battery twice to 50% than it does to fill it to 100% once (see the prior post on an explanation why).  Minimally you want to charge to have enough range to get your next stop plus a buffer for unexpected detours.  Anything beyond that is wasted time.

For a trip, I would suggest the following as a template to start your planning:

  1. Start the trip at home with a 100% charge
  2. Mid-morning break: stop, stretch, grab snacks and charge just enough to get to your next stop (+ safety buffer)
  3. Lunch: stop for lunch and charge to 90%+
  4. Mid-afternoon break: stop, stretch, grab snacks and charge just enough to get to your next stop (+ safety buffer)
  5. Dinner: stop for dinner and charge to 90%+
  6. Late-evening break: stop, stretch, grab snacks and charge just enough to get to your next stop (+ safety buffer)
  7. Destination/Hotel: stop for night and charge to 100%

Some other thoughts on charging:

  • As far as the safety buffer goes, I like to keep buffer of 15%-20% or 40-50 miles–again, use that as a starting point and adjust as your confidence grows.
  • If you do not have charging at or near your destination, at your last charging stop, make sure you add enough range to get to your destination and back to that charging spot plus cover any driving around you plan to do at the destination.

Things that Impact Range

There are a number of environmental factors that can impact your range when you travel.  The big three are speed, temperature and elevation:

Speed

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Source: tesla.com

For those of us born with lead feet, learning to drive a bit slower can be a challenge, but on longer trips it can pay off.  The reason speed matters is that wind resistance grows as a square of velocity.  If you look at the above chart, the “cost” of going 70 mph vs 80 mph is about 30 miles of range.  Now does this mean you need to drive 65 mph everywhere?  No, just that if you are going to go faster, you need to take that into account when you are planning your trip and your charging stops. Again, with a few trips under your belt you will start to get an intuitive feel for speed and range.

The other change in behavior is to look at total trip time vs traveling time.  Sure going faster will get you to your next charger faster, but you are going to also spend more time charging once you get there.  Owner consensus is that somewhere around 70mph gives you the best balance between driving speed and charging time.

Changes in Elevation

Going uphill will gulp down range.  As a general rule of thumb, you will lose about  6 miles of range of every 1,000 feet of elevation.  The good news is that you will get 80%+ of that back on the way back down because of regeneration.  Going to Lake Tahoe is always a fun trip, especially the first time, because your range plummets and even seasoned travelers will be checking their numbers.  However, on the way back, you’ll end up with almost the same range numbers as you started because its one long downhill coast.

Low Temperatures

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Source:tesla.com

When its really cold outside (say sub 40F), assume you will see a 30% loss of range–again, a good place to start and adjust as your experience grows.  The modeling tools above will take ambient temperature into account.  While range loss in cold weather is inescapable, there are a couple of things you can do to lessen the impact of cold weather:

  • For your regular commute, if you have a regular schedule, turn on the smart  pre-conditioning–this will use the wall power to warm your battery instead of using the battery itself
  • For a one-time trip, either use the mobile app to turn on the climate control about an hour before you leave or set the car to charge to 95% the night before and then charge to 100% about an hour before you leave.  Again this uses wall power to warm the battery and cabin instead of the battery.
  • Turn on range mode

Other Factors

Aerodynamics: using a roof rack or trailer will reduce range

Wind: driving into a headwind will reduce range.  Driving 60mph into a 20mph headwind generates the same wind resistance as driving 80mph on a clear day

Rapid Temperature Drops:  a rapid temperature drop, especially in the spring and fall when the temps go from moderate to the 40s around sunset can cause the battery heater to kick on and result in a sudden unexpected drop in remaining range

Just for some context, all these factors also reduce the milage of gasoline or diesel powered cars, its just more evident with your Tesla since it is throwing all this data at you.

What if I Run Low on Charge?

So, if you still think you are going to be short of range, there are a couple of things you can do to eke out a few extra miles (bring up the Energy app and the “Trip” tab to see how you are doing):

Slow Down  Dropping your speed my 10mph can have a remarkable impact on range if you do it safely (i.e. don’t suddenly slow down I the fast lane).  If you are on the freeway, getting off and taking surface roads can also be a helpful strategy as it allows you to go even slower and take advantage of regen braking

Use TACC or Cruise Control Teslas are remarkably efficient when going at a steady speed–much of your range gets burned changing speed and using TACC or CC helps you maintain a steady speed and smooth out your acceleration and deceleration

Follow Someone Following another vehicle (at a safe distance, don’t tailgate) will reduce wind resistance and increase range

Turn on Range Mode Note that among other things, Range Mode limits energy spent heating or cooling the cabin.

Find a Charger Now is the time to fire up Plugshare and find nearby chargers and add a few miles of range back.

If you do run out of electricity, try and pull over in a safe spot and call Tesla Roadside Assistance.  They will dispatch a flatbed tow truck to take you to the closest charger.

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