How much range do you need?

By |2019-03-25T12:48:45+00:00March 24th, 2019|Categories: General|0 Comments

When discussing electric cars, people are infatuated with range … and range anxiety – so how much range do you need?

My first electric car was the Nissan Leaf, with a rated EPA range of 73 miles (2012 model – current Leafs have far more range).  I quickly learned the many limits of having this limited capacity.  It did not help that for over a year I had a 74+ mile commute which I successfully did on a daily basis with the Leaf, and would arrive home with 5-10 miles of range remaining … impossible you say – which brings me to the first point on range:

No different than a gas car, an electric car stores energy – and that energy can be expended in multiple ways.  Just like many gas cars will show “DTE” (Distance To Empty), which can be over (or under) accurate to your specific driving conditions – an electric car is the same – the rated range is an estimated distance the car can travel based on a whole set of assumptions.  If you have a Tesla (or a Porsche) and enjoy driving super aggressively then you will need to “refill” the battery (or gas tank in the case of a Porsche) more frequently – drive super casually then you will get more out of your battery/gas tank.

To show an extreme – there is something called “Hypermiling” – where a person drives in a hyper efficient manner, to see just how far they can travel on a single charge – the record for the Tesla Model 3 is over 600 miles (even though the rated range of the car at testing was 310 miles)!!!

Hypermiling  is not reality for day to day driving … it does highlight that when you see a range number for an electric vehicle, you need to understand that its not its an exact measure – what is an exact measure is the amount of energy the battery will store (similar to a gas car with the amount of gas a tank will store) – what is not exact, is how you drive it, and the environmental conditions (for instance, driving up a mountain vs. down a mountain – highway vs. city …) that will result in more or less distance you can travel from a full charge.

So how much range do you need? Below is a decision map I created to help make your decision:

 

How do I come up with the above suggestions?  Following previous blog entries, I recommend targeting a car that has a range that is 2-4 times your regular peak day (so if your regular peak day is 50 miles, target a car with 100-200 miles of range).  What does that mean?   If your daily commute to work is your regular peak, use that.  If your driving more on a weekend to haul around the kids and do errands, use that as your regular peak day.   A key factor is the single day number – with a gas car that you typically fill up when your at ~1/4 tank, with an electric car you can charge every night – just plug it in when you get home.

So why a car with 2-4 times your regular peak daily range needs?  A few factors:

  • Its best to regularly charge an electric car to 70-90% of its capacity – this will increase the longevity of the battery.  Currently, I target 80%
  • Just like a gas car, most people don’t like to drive their car to virtually empty – so assume you would want at least 10-20% remaining before you start getting worried
  • That leaves ~60-80% of the battery/range that you will have available – but … as noted above, there are many factors that will allow the energy in the battery to take you further, or shorter then the rated range – so you need to account for days where you may drive more aggressively, or blast the A/C, or blast the heating …
  • You also want to have a little room for those exception days
  • You don’t want to have range anxiety!

You also need to consider your need/or interest in taking the car on roadtrips.   Please keep in mind, that if you do one roadtrip a year, you may be best off renting a car for that roadtrip!  If you plan to do a cross-country trip once over the next 5 years, you may want to think about whether it should factor into your car buying decision (again, maybe best to rent a car for that one expedition!).

Roadtripping with an electric car can be an awesome experience!

How much range will be needed if you plan roadtrips?

It depends on the type of roadtrips you plan to regularly take – so let me split them up:

  1. Short roadtrips – 1-3 hour drive (60-200 miles) – A car with a 200+ mile range is ideal, as you will at most need one small stop along the way to “top up”.  While the current Nissan Leaf base (150 miles) can take this trip, you will almost definitely need to charge along the way, and you will need a reasonable charge time.  The Honda Clarity (89 miles) can also do it, but you will need to work through specific stops to ensure you will make it.  At this point, most of the popular electric cars have over 200 miles of range (Tesla, Chevy Bolt, Nissan Leaf e+), so this type of trip should be easy
  2. Mid length roadtrips – 3-10 hour  (200-600 miles) – A car with a 300+ mile range is ideal, as you will likely stop 1-3 times, and the total time needed to charge the car will be similar (or less) than the time you’d want to stop to go to the bathroom, eat, stretch.  For instance, mapping with EV Trip Planner Washington DC-Boston, a 440 mile trip, there are two stops with a total of 25 minutes of charging time!  I can’t imagine travelling for 7 hours, and not needing at least 25 minutes of time for bathroom, eating, stretching!   Can you do it with a 200+ mile range car – yes, but as you get closer to 500 mile trips, you will need to stop more frequently, and the total time spent at charging stations will increase
  3. Long road trips – 10+ hours (600+ miles) – really I would recommend a 300+ mile range car – as otherwise, you will need to stop really frequently and stop for long periods of time.  Let me highlight that fast chargers/superchargers re-charge the first 50% of the battery super fast, then the balance takes longer to recharge (incrementally as you get closer to 100%).  If you have a 200 mile range car, you will go an initial ~150-180 miles, stop, and then charging for an additional ~80 miles will go fast, but charging for an additional 150-180 miles will take far more time.  With a 300 mile range car, you can drive an initial 250-270 miles, stop, then quickly add another 150-180 miles of range – so you can drive ~4 hours, stop for a short period of time, then drive in 3 hour increments – so a 10 hour drive day can have 2-3 stops.  On a longer trip (over 600 miles), even with a 300 mile+ range car you will need more stopping time than with a gas car, but depending on how you are doing the trip, this may work well for you

Other considerations for long trips:

  1. Tesla Super Chargers v3 – this recent announcement, when built out will have a dramatic improvement on long road trips – with v3, a 300 mile range car will be able to go on long trips with a far closer amount of stop time as a gas car – you will still need to plan stops every ~3 hours, but these stops may be as little as 15-20 minutes – again, this should closely match your minimum need for bathroom, food and stretching
  2. Right now, there is no better car for roadtrips than the Tesla – this is because they are the only electric cars currently available with 300+ miles of range and because of the Super Charger network.  In terms of the Super Charger network, there are thousands of non-Tesla fast chargers in place, but the Super Charger Network has a few key advantages for roadtrips:
    1. The Tesla navigation has built in logic to identify when charging will be needed, and to add interim stops on the navigation at Tesla Super Chargers
    2. The Tesla Super Chargers blanket the highways – where you need chargers for roadtrips
    3. Tesla Super Chargers are super easy to use – just plug in the car and charging starts – with the non-Tesla chargers you need an account, and you need to go through a verification process before you start charging
    4. Tesla Super Chargers all have multiple chargers – usually 8+.  There are many non-Tesla charging locations with only one or two fast chargers – if someone is using it, or parked in it, tough luck

Other considerations.  There are a few factors that may affect the range you may need:

  1. You drive fast on highways – yes, if you typically drive 80+ miles/hour, then you will consume more energy per mile driven, and you will get less range from your car
  2. You need to drive long distance in really cold weather – cold weather has two impacts on an Electric vehicle: 1-a battery is not as efficient at lower temperatures and 2-heating is powered by the battery.  When I say cold, I would really consider sub 32F or sub 0C type of weather – how much less distance will you get – it can be 10-30% (in my experience), based on a variety of factors
  3.  You don’t own a 220v charger – most 220v chargers will charge at a rate of 25+ miles/hour – it should easily replenish the battery after your typical day.  Some people only have a 120v charger, or can only access a 220v charger outside the home.  Keep in mind a 120v charger will charge at a rate of 3-4 miles/hour, and if you are using a charger outside the home, factor in how frequently you’ll be able to charge

Final thoughts …

When I owned my Nissan Leaf, I quickly understood what range anxiety was – whether it was a typical weekend day where I might need to make multiple trips easily adding up to over 70 miles, or when I started using it for my 70+ mile commute.  To achieve these results I would do all sorts of things, like not use the AC in the summer or the heat in the winter – or I would travel at ~50 miles/hour on the highway to extend the range (annoying everyone around me).  Clearly this was not a good range fit for a person with the driving profile I had.

Everything changed with the Tesla Model 3 – with 300+ miles of range, my primary thought is whether I should charge to 70,80 or 90%, as at any of these levels there is still plenty of battery left for virtually any daily driving I need (who drives over 200 miles in a day when they are not taking a roadtrip!!!).  I have no second thought about using AC or heating, or my driving style (and the Tesla encourages more aggressive driving!) – I no longer have any range anxiety, and can’t imagine most people would with this car.

So – follow the above guidelines and you will love everything about your electric car and will not have fear of running out of charge!

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