What are the most efficient electric cars?

June 30, 2018 by Andy Miles

The Question

This was a question about the effectiveness of electric vehicles that we posed me recently, and apart from thinking that the Hyundai Ioniq has to be quite efficient because it gets about 120 miles on its 28kWh battery, I could not answer. It sometimes happens that only when someone asks a fairly obvious question that we think – "heck, I never really thought about it". In my case, I have the excuse that if I look at an EV to buy, I would be more interested in the range and price, rather than the efficiency, but once the question is asked, I felt annoyed by her and I had to find the answer.

Image credit – "Hyundai"

The answer

He demanded a lot of technical research on a wide range of cars coming up with an answer. The basic idea is that an EV is there to convert electrical energy into kinetic energy, or less technically, electricity in for miles of travel out . What we would need to establish for each car is the size of the battery (which is roughly equivalent to the amount of electricity needed to charge it) and the real reach of the real world reached.

The size of the battery is not a perfect indicator because a battery can not be drained completely, so the full capacity can not be used. The indicated capacity is not the full capacity or the indicated capacity is not fully available. In addition, some of the electrical energy is lost in the internal charging system of the car, so the power input may be slightly higher than the battery capacity. However, it is not an unreasonable assumption that all these variations will be pretty much the same for all electric vehicles, so the indicated battery capacity can be considered a reasonable measure.

The scope is more difficult to define. In a recent test drive with a 2018 Nissan Leaf, the range claimed by the Nissan dealer was 150 miles, the best beach reached was 202 miles, and the overall range I've reached on a trip 175 miles was 185 miles per charge. See 175 miles in the 2018 Nissan LEAF of "150 miles" (#CleanTechnica Review) for more information on this disc.

Any car would give a similar range of range, depending on how they are driven. The most accurate test would be to measure the precise current consumption over a measured distance, but this would require a research program involving driving and measuring all the different cars, which would be far beyond my resources. Even when doing this, the efficiency varies depending on how the car is driven: a hard and fast driving car in rally style will be far less efficient than the same car driven in a quiet driver style. Cars should all be driven in the same way. See how EV range is affected by fast acceleration

Data

Not being able to do such a research project, I have to rely on data that I can find that already exists. The battery capacity and an average range for each of a car list is the best I can find. The average range, divided by the battery capacity, to get miles per kWh, seems the easiest way to calculate the efficiency. The averages I obtained are derived from the range achieved in urban driving and highway driving, both in summer and in winter, so that four different range values ​​for each car are used to obtain the average . Some cars, and possibly most cars, have different driving modes – for example, Ioniq has the "Sport" mode and the Nissan Leaf has modes B and D, which can be changed with the " eco "to save battery. The level of efficiency would be different in the different modes, but the figures I've used seem to be for the mode and the standard version, and so are all comparable. On this basis, after examining a number of different motor coaches, they appear as follows in the table below:

Motorway cars in order of miles per kWh

About the Author

Andy Miles Child, I had unrealistic expectation that I would like to learn , and understand, absolutely everything, during growth. Now, at the other end of life, I am fully aware of all that I have not learned, and that I do not understand, yet I am interested in everything. My education, starting with a degree in arts, and going from graduate studies, in everything from computer science, to hypnotism, reflects my broad interests. For 20 years, I have worked in the local government, and I am now retired, living in North Leicestershire in the UK, with plenty of time to do what I want. I've always had a keen interest in all alternatives, which include renewable energy and energy efficiency and, of course, electric vehicles. So, of course, I have taken possession of an EV, now that they are affordable and convenient means of transportation. Writing is also one of my great pleasures, so writing on electric vehicles and environmental issues is a natural evolution for me. You can find my work on EV Obsession, and CleanTechnica, and you can also follow me on twitter .