Why mpg is misleading

This and more, here at Green Car Reports. The original US military Humvee formed the basis for a brand—Hummer. Thousands of DC fast charging connectors will help owners in urban areas make sure their EV stays charged, even if home or work charging aren't guaranteed. The deal is on with Foxconn—but that won't speed up the arrival of the Endurance electric pickup, the company confirmed Thursday. There might be a connection once again between a civilian Hummer and a military vehicle—if the government is convinced on its worth.

Subaru reveals its electric car, and Kia teases the future of electric SUVs from the brand a bit more. Geely shows its Tesla Semi rival. And could a new method work for keeping EV charging cables cool? The first mass-production electric vehicle from Subaru A Geely brand plans to roll out the sustainability-themed, data-focused electric semi to global markets beginning in A cooling method being explored by Ford and Purdue University is considering using coolant phase changes instead of just circulating liquid; that could introduce packaging advantages and make the system more efficient.

Subaru's new electric SUV, the Solterra, makes its global debut with promising off-road capability and no yoke thank goodness. Americans aren't stupid.

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Stephen Edelstein November 14, Bengt Halvorson November 13, Bengt Halvorson November 12, GM and EVgo step up fast-charging network to ease urban EV ownership, electric ride hailing Thousands of DC fast charging connectors will help owners in urban areas make sure their EV stays charged, even if home or work charging aren't guaranteed. Lordstown Endurance electric truck delayed to Q3 , as Foxconn acquires factory The deal is on with Foxconn—but that won't speed up the arrival of the Endurance electric pickup, the company confirmed Thursday.

Bengt Halvorson November 11, Which driver will save the most fuel? This is wrong. To see why, let me re-phrase my simple example. Two women are considering upgrading their cars. One is thinking about switching from a 5 gallons per miles car to a 4 gallons per miles car.

A second woman is thinking of switching from a 4 gallons per miles car to a 3. Which woman will save the most fuel? You can clearly see that it is the first woman. She saves 1 gallon per miles, whereas the second saves 0. This can be demonstrated graphically as well. Let us start with a 20 MPG car and consider how much fuel is saved per miles as we improve the fuel efficiency of the car.

The savings per miles for all fuel efficiencies up to 50 MPG are shown below. Far from it. The fuel saved by switching from a 20 to 28 MPG car is roughly the same as switching from a 28 to a 50 mpg car. Yet, the fuel saved is the same. The consequences of this are obvious. If you want to reduce the environmental footprint of cars, you should not simply aim to reduce average miles per gallon.

The average fuel efficiency of new passenger vehicles on American roads is Persuading someone to switch from an average vehicle to a 50 MPG vehicle will have greater impact on average mpg than getting someone to ditch their 15 MPG SUV for an average efficiency vehicle.

Yet, getting the SUV driver to switch will reduce fuel consumption more. So, I will make a two-step proposal. First, we switch from measuring fuel efficiency in miles per gallon to measuring it in gallons per miles. And second, we then switch from gallons per miles to litres per kilometres. But before this we should do something about the absurdity of people driving around in excessively large vehicles that not only needlessly pollute cities, but also do immense damage to the planet.

Wondering when the US will catch up and abandon their archaic confused measurement system. Though based on the old British system even they have abandoned it! Robert, we have many, many issues which are of supreme national embarrassment.

Acknowledged, and grateful to be included in your list of developed countries. Robert, unfortunately many Consumers do not focus solely on fuel efficiency when making vehicle purchasing decisions. The priority of fuel costs or fuel efficiency depends on the income level or ability of the Consumer to pay for owning and operating a given vehicle.

One factor you have overlooked in the possible confusion relative to vehicle fuel efficiency is the recent U. Raise the fuel tax to NW-European levels. Then people will drive more slowly.

Commit for a regular increase of the tax during the next 20years. So people will not only drive more slowly, but also buy only very fuel-efficient cars. Spend the increased tax revenues partly to lower general taxes e. VAT , improve public transport, and stimulate renewable. And for cars in the fleets of countries where good mileage is valued, it matters even less.

The incremental saving from 55 mpg to 60 mpg is very small. However, a 5 mpg improvement in a tractor trailer can represent a doubling of fuel efficiency. The federal government has attempted to bridge this with MPGe miles per gallon-equivalent but even that or its reciprocal is subject to big assumptions about appropriate energy conversion rates.

With this option, students complete a one-question online quiz prior to class. However, this choice saves only 3 gallons per miles, whereas the other choice saves 5 gallons per miles. To help students understand the MPG illusion, they can be instructed to follow up the quiz by viewing the video below, by visiting the MPG illusion website , or by reading the original Science report and its supporting materials.

Instructors can then build on this material in a lecture or classroom discussion. In-Class Quiz. The in-class quiz, based on Study 1 of Larrick and Soll , can be distributed as a handout, given on a lecture slide, or collected prior to a lecture if the instructor wants to present a summary of student responses.

The quiz asks students to assume that a person drives 10, miles per year and is considering an upgrade to a more fuel-efficient vehicle. They are asked to rank five vehicle upgrades in order of their benefit to the environment, using "1" for the largest gas savings and "5" for the smallest.

Students most often rank the upgrades according to the size of linear improvement C first, followed by A, E, B, and D. In reality, however, the correct order is A-E. For instance, A and B both save more gas than C. After the quiz, instructors may wish to use or adapt relevant PowerPoint slides to explain how MPG can be misleading and to start a discussion about better measures for making greenhouse gas decisions.

In addition, students might be assigned a follow up reading such as those mentioned earlier. This classroom action teaching activity is especially well-suited to introduce a lecture or discussion on the link between psychology and climate change. More generally, decision makers need clear information about the greenhouse gas consequences of their transportation, diet, work, and housing choices — that is, the main contributors to their "carbon footprint.

The MPGillusion. This calculator provides a practical tool for students and others to compare fuel efficiency across cars, and was designed as the sort of tool that the U. Environmental Protection Agency FuelEconomy. In sum, learning about the MPG illusion can help students make better decisions for themselves and see the link between psychology and climate change.

Here are a couple tips based on my experience teaching about the MPG illusion:.