Overview of Vehicle Range
No matter what kind of car you drive – gasoline, hybrid, plug-in hybrid, or electric – filling up is an inconvenience. Whether you’re just going through your daily routine or on a road trip having to stop is a pain, especially in the winter or in bad weather. Which is why range is so important.
While range is the number-one thing people talk about when it comes to electric cars, it matters to us even if we drive a gasoline vehicle. Many drivers will talk about how many miles they get out of a tank of gas, versus what kind of miles per gallon it gets.
That’s because, ultimately, the convenience of range is more important. We’d likely rather drive a thirstier car that will go longer between (more expensive) fill-ups than a super-efficient car that requires frequent stops.
Depending on the type of green car you’re looking at, figuring out its range can be as simple as reading a spec sheet or looking at a web site. Or you might need to do a little bit of math.
If you’re researching gasoline cars it can be a little bit frustrating to figure out what vehicles offer you the most range – the EPA doesn’t rate gas cars for range the same way, they do for electric cars. But the EPA does rate gasoline cars for city and highway miles per gallon (MPG), which you can use to calculate a vehicle’s range.
Go to the vehicle manufacturer’s website and look up the fuel capacity of the vehicle you are considering. Once you know how many gallons of gasoline the vehicle can hold, you can multiply that capacity by the miles per gallon to determine range.
For instance, if the car you are investigating has a 15-gallon gas tank and gets 30 miles per gallon on the highway, expect a highway driving range of 450 miles.
Hybrid and Plug-In Hybrid Cars
Hybrid cars use a combination of gasoline and electric power. Many hybrid cars can run on electric alone for short periods of time, which can complicate the range calculation a little bit. The easiest figure to use when calculating a hybrid car’s range is the EPA’s MPGe (miles per gallon equivalent) number.
MPGe is an energy efficiency metric that was created by the U.S. Environmental Protection Agency in 2010, as the first plug-in hybrid and electric vehicle models were being introduced to the market. Its purpose is to relate the amount of energy used by alternative-fuel vehicles to that of their traditional gas-powered counterparts.
Using the MPGe figure, you can calculate the total range of a hybrid vehicle using the fuel tank capacity -- the same as you would for a gasoline vehicle. A hybrid or plug-in hybrid with a 15-gallon gas tank that gets 40 miles per gallon on the highway would deliver a range of 600 miles.
The total distance an electric car can travel is determined by an electric car’s battery capacity and its overall efficiency. Battery capacity is measured in kilowatt-hours (kWh) – and the bigger the number, the better (like having a bigger gas tank).
Overall vehicle efficiency is the result of multiple variables including size, frontal area, weight, and performance. Efficiency can be measured in multiple ways. Using basic math lets you determine how far you can go on a single charge.
There are two easy-to-find figures that can help you calculate an electric car’s overall range.
One method is measured in MPkWh, or miles per kilowatt-hour. The higher the MPkWh, the more efficient the vehicle. Multiply the MPkWh rating by the kWh size of the battery to get the theoretical range. For instance, an EV with a 100-kWh battery rated at 2.5 MPkWh will deliver range of about 250 miles.
You may also see ratings for kWh/100 miles. Divide the battery’s capacity by the kWh/100 miles rating then multiply by 100 to determine your range. An EV with a 75-kWh battery rated at 35 kWh/100 miles will go 214 miles on a full charge.
How to Increase Your Range
Now that you know how much range your car is capable of, how do you maximize the range you get out of every tank of gas, every battery charge, or a combination of both? While each type of vehicle has its own nuances, there are some tips that apply to all vehicles.
Ensure your vehicle isn’t carrying around any unnecessary baggage – in terms of weight and aerodynamics. Leave behind stuff you don’t need; the extra weight is literally dragging you down. Remove roof rails, bike racks and other exterior accessories unless they are needed.
Check that your tires are in good condition and at the correct pressure. As the only point of contact between your electric car and the road, an improperly inflated tire can have an outsized effect on how hard your car must work.
Adjust your driving style – driving more smoothly and carefully can help to improve your miles per gallon and increase the range from every charge. You’d be surprised at the difference a few miles an hour makes. Slowing down your highway cruising speed by 5 mph will have a significant impact on your energy consumption. You’ll increase your range and may discover that you’re more relaxed as well.
Unnecessary braking, steering, and accelerating wastes precious energy and reduces the comfort of your passengers. Anticipating situations that will arise while driving means that you’ll spend less time and energy reacting. Use smaller throttle openings to build up speed over time. If you can anticipate the need to slow down, you can lift off the throttle earlier to coast and help charge the battery with regenerative braking.
By driving with a little bit more care, you’d be surprised at how much extra range you’ll get – no matter what kind of vehicle you drive!