50 Articles

Why do automatic transmissions now get better fuel efficiency than manuals?

Not so long ago, it was common for automatic transmissions to be referred to as slushboxes, since that's how they often behaved. Rather than use a mechanical clutch, traditional automatic transmissions use a fluid coupling between the engine and the gear-sets to transmit drive torque. This provides some benefits, but isn't a perfect system.

Who will be the main players in the electric vehicle space?

2012 Renault Fluence Z.E.

What realistic electric vehicle recharging options are there for apartment dwellers?

One of the challenges to making electric vehicles (EVs) "work" in the real world is figuring out how, where and when to recharge them. If you have a garage, then those questions kind of answer themsleves. You come home, take 15 seconds to plug the car into the wall and undo the plug in the morning with a full charge. One previous Greenlings looked at EV charging basics and another Greenlings explained some of the options for home recharging. We recommend reading through those pieces as a primer

What's a light-duty truck, and why should we care?

2009 Chrysler PT Cruiser – Click above for high-res image gallery


Driving In Circles Can Sometimes Be Good For The Planet

Humans are competitive creatures who have raced against each other in one form or another for millennia. Is this still a good idea?

What's the point of concept cars?

Honda P-NUT – click above for high-res image gallery

Guide to Common Green Acronymns

Deciphering the new vocabulary of the green car movement can sometimes be a real head scratcher. To alleviate as much confusion as possible, we would like to present our readers with a list of common acronyms and what they mean, with plenty of links for more information. If you have some TLAs (that's three-letter acronyms) that you'd like us to add to our glossary, just let us know in the comments.

What's the difference between kW and kWh?

Understanding electric and plug-in vehicles requires a slightly different knowledge set than what mechanics and drivers have needed to know for decades. One of the most obvious new concepts is the large battery pack and electric motor added to the car. The capacity values of these devices can be written using kW (kilowatt) and kWh (kilowatt hours), but don't think that a 90 kW motor is anything like a 90 kWh battery pack. That little h makes a big difference. Exactly what is the difference? Well

Why does mileage drop in winter?

This week's Greenlings topic came to us from another reader tip. Don asked why his fuel economy suffers so much in winter weather. In his own experience, mileage drops about 10 percent when the temperatures go from the 60-70 F range to near freezing. This is consistent with our own experience and in fact we've seen even bigger drops than that when testing hybrid vehicles in winter conditions.

How do I plug in an electric vehicle at home?

As electric vehicles begin to find their way to peoples driveways and garages, knowing what's involved with charging up the batteries becomes more necessary. Over the years, electric vehicles (EVs) have used different kinds of batteries and employed different types of chargers and connectors, so the car that you buy next year may not work with the charger you picked up on eBay last month. While in the future charging may be as simple as parking in your garage or driveway and having an automated

How does weight affect a vehicle's efficiency?

Over the last few decades, the average weight of a vehicle sold in the U.S. climbed steadily after we got over the oil embargoes of the 1970s. Today, though, auto companies are putting a lot of effort into reducing weight – Lotus set up an entire lightweight structures division, BMW is investing millions into carbon fiber and Jaguar loves aluminum – because every ounce you take out of a car improves the vehicle's performance and fuel economy. Options for weight savings that automaker

Why can't Americans have good, small diesels?

It was big news when the Obama Administration updated CAFE requirements in May to a new and higher national MPG standard of 42 mpg for cars (26 mpg for light trucks) by 2016. The higher standards will start increasing with 2011 model year vehicles. But what is CAFE? And how do these new numbers – before the raise, cars needed to average 27.5 mpg and trucks 24 mpg – change what will be available in dealerships in the coming decade?

Recently, we received the following question from a reader:

We like to answer reader questions with our Greenlings series whenever possible, and thought that Timothy H. had a good topic. He sent in the following question/suggestion about straight vegetable oil (SVO):

Renault Zero Emission line-up - Click for high-res image gallery

2011 Chevy Volt - Click above for high-res image gallery

For the last century or so, cars and trucks have predominantly been formed from one material in particular: steel. It's not hard to see why – steel is relatively inexpensive, highly abundant and easy to form into somewhat complex shapes that can be repaired with mostly basic tools.

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