Practical Considerations for Owning an Electric Car

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Practical Considerations for Owning an Electric Car

What sorts of things must one consider and of which to be aware before purchasing an electric car (EV)? The main things to know are discussed below. Should you have questions, feel free to ask in the comments section.

The most common concern is range anxiety; that is, how far can the car go on a full charge of the battery? This is determined only in part by the size of the battery. The published range should be listed in the car specifications. However, the driving conditions upon which the datum is based are usually not given. I would advise that you get the biggest battery available that you can afford assuming various sizes (ranges) are available as an option.

Many variables impinge upon the actual range one can expect for a given battery size. Variables include battery manufacturer and specs, driving style, the load of passengers and cargo, electric equipment in use (e.g., air conditioning or heat, stereo, lights), tire condition and pressure, rear or all-wheel drive, and especially average speed of travel.

It seems likely that battery range values given in the car’s specs are for city driving at relatively low speeds. That’s a useful datum since most of the driving we do is around town locally. But what if you want to go on a road trip at highway speeds? Highway driving can significantly reduce the effective range of the battery because running the electric motor(s) that propels the car at high speeds drains the battery faster than low-speed driving.

On recent road trips, I collected data to determine the effect of average speed on battery usage. Air conditioning and stereo were in use throughout the trips. I was the only passenger and there was no significant cargo load.

The published range of my battery is 310 miles. The calculated range for several estimated  average speeds was as follows:

75 mph: calculated range 238-243 miles (two separate legs).

70 mph: calculated range 250 miles (one leg).

Local driving: calculated range 300 miles or approximately 3 miles for each 1% of battery charge.

Limitations in the data:

It’s important to note that the average speeds above are a rough estimate. Consequently, calculated ranges are also estimates. Speed on the highway is highly variable due to traffic speed fluctuation, passing speeds, etc.

Calculations are based on trip legs of 100 -124 miles. Longer leg distances may give somewhat different results. Ranges above are intended to illustrate the effect of speed versus battery range. They should not be used as firm metrics for trip planning. Because the variables involved, not the least of which is driving style, each driver should estimate their own ranges.

Tesla has a navigation feature called trip planning that will show you the route, Superchargers and destination chargers along the route, and the estimated level of charge upon reaching your destination. It is extremely helpful for planing trips and minimizes any range anxiety.

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Another common concern is the availability of charging stations. This should not be an issue for local driving around town if you install a separate electrical circuit in your home dedicated to charging your car. Generally, this entails hiring an electrician to install a separate 240 volt, 50 amp circuit. Using my car as an example, it takes approximately 10 hours for a full charge, or 30 miles of range per charging hour at 32 amps. Charging from 110 volt, 20 amp circuits provide approximately 3 miles of range per hour. As you can see, charging rate depends on amperage delivered by the charging source. It is also limited by the charging circuitry of the car in question.

Tesla Supercharging stations can deliver very high charging rates and can deliver a full charge in as little as an hour or so depending on how many cars are charging from the same central charging source. As long as your round trip commute and/or daily errands do not exceed say 80% of your battery range, then you simply charge the car at home each night to have it ready for the next day. In my case, I am able to program my car to begin charging at a specific time each day that it is attached to my home charging circuit (e.g., midnight when the electricity rates are lowest).

In addition, more and more public access charging stations may be found around town at locations such as libraries, city or county facilities, some parking garages or certain locations on the street. Availability varies across the country so you will want to research your locality. Here is one website with examples of some charge providers

Tesla has an extensive and expanding network of Superchargers around the country usually located in close proximity to major interstate highways and turnpikes to facilitate recharging during road trips. In addition, there is a network of so-called destination charging stations for Tesla cars that are sponsored primarily by some hotels, restaurants, etc. These are generally similar to home charging circuits in terms of speed. Some destinations may provide the service to guests at no cost, while others may charge a nominal fee.

Tesla charging hook ups are configured specifically for Tesla cars. Tesla cars come with an adapter for connection with most public charging stations.

As more and more electric cars hit the street and more carmakers produce them, we can expect the charging infrastructure to grow accordingly because adequate charging infrastructure is an important element in many buyers’ decision process. Hopefully, in time, car connection receptacles and cables will be standardized across all car makes and charging stations.

EV batteries have a limited lifetime. Just like your smart phone, the EV battery will decline in efficiency over time. Batteries used in today’s EV and hybrid cars are usually warranted for 8 years. Actual battery life will vary according to the owner’s use and charging habits.

Generally, it is recommended that one does not run the battery down below 30% and a full charge should be reserved for long road trips. Keeping the battery charge between 30-80% is recommended for maximum battery life. Conversely, if you run the battery down below 30% and/or charge above 80-90% frequently, battery life will be reduced.

We live in a very exciting time concerning technological progress. The dominance of EVs may come much faster than many expect (my prediction is within the next five years). Concerns about climate change, negative health effects of combustion emissions, technophilia, the advent of the self-driving car, and especially the fun of driving an EV will all be factors contributing to the rapid rise of the electric vehicle. I encourage everyone to take a test drive or ride in an EV so you can discover and plan for what your next vehicle will be.

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