efficiency

Can Apple's Snow Leopard save you money?

Apple's OSX Snow Leopard update offers several noteworthy enhancements, and plenty of behind-the-scenes tweaks--but has anything in the operating system changed in regard to energy efficiency?

We took a 17-inch MacBook Pro and ran it though our standard energy use tests, first under OSX 10.5.6 (a.k.a. Leopard) and then after we installed Snow Leopard, which brought us up to OSX 10.6. Our test system, already Energy Star-compliant, had a 2.66GHz Intel Core 2 Duo CPU, and we had the discrete Nvidia GeForce 9600 graphics turned on.

The differences were minor, but we were … Read more

BMW reveals its Vision for the future

The Frankfurt auto show rapidly approaches, which means that it's time for yet another dull BMW EfficientDynamics concept to mildly pique our interest with...wait, whoa! WHAT IS THAT?

The recently unveiled BMW Vision EfficientDynamics concept maintains the hallmarks of what makes a BMW a BMW (the kidney grills, the Hofmeister kink, and hopefully, the high level of performance), but tosses everything else out of the window to create a bizarre amalgamation of M car performance, fuel efficiency, and insectoid aesthetics.

Let's start with the power train.

The Vision concept is powered by a 1.5-liter, turbodiesel three-cylinder mounted amidships and two electric motors--one at each axle. Direct injection and a variable intake geometry turbocharger help the diesel engine to output 163 horsepower and 214 pound-feet of peak torque to the rear wheels through BMW's six-speed DCT transmission.

The rear electric motor outputs a consistent 33 horsepower and is able to reach a peak of up to 51 horsepower. Maximum torque for the rear electric motor is 214 pound-feet. Meanwhile, a second electric motor at the front axle offers continuous output of 80 horsepower and peak torque of 162 pound-feet. An extra 112 horsepower are available for a period of up to 30 seconds, and, for a 10-second "burst" the electric motor is able to develop 139 horsepower.

Overall system output is 356 horsepower, and peak torque is 590 pound-feet during that 30 second burst (for passing maneuvers, etc). Acceleration from 0-to-62 mph is achieved in 4.8 seconds, and top speed is an electronically limited 155 mph.

The system can run under diesel power, electric power, or a combination of the two. The engine configuration affords the Vision all-wheel drive when operating in all-electric mode. The electric engines are powered by a total of 98 lithium polymer cells developing continuous output of 600 amps with a maximum 30-second burst output of 1,200 amps. The batteries are recharged through a combination of diesel generation, regenerative braking, or plug-in charging. As a result, the Vision has two refilling flaps, one for diesel fuel and one for electricity. Average fuel consumption is 62.6 mpg on the EU test cycle.

The BMW Vision concept's ubersleek looks are the result of efficient aerodynamics and lightweight construction.

With the mid-mounted diesel engine, the Vision can have a low nose. Active louvers in front of the radiator close completely when there is little need for cooling, such as when running in all electric mode. The vehicle's low, sleek design results in an overall vehicle drag coefficient of just 0.22. The concept rolls on oddly huge (21 inch), low-rolling resistance tires. The big wheel and 195 millimeter profile supposedly provides a big enough contact patch to keep the Vision agile, as well as efficient, while wheel covers reduce turbulence caused by the spinning wheels.

Most of the body is made of transparent composites (which darken when exposed to UV light) and the chassis and suspension are made completely of aluminum, resulting in a curb weight of 3,076 pounds.

The BMW Vision EfficientDynamics concept will be unveiled, along with the BMW ActiveHybrid X6 and BMW ActiveHybrid 7 production models, at the 2009 Frankfurt auto show, so stay tuned for more coverage. In the meantime, make the jump to see the BMW Vision concept in motion.… Read more

Is the GM Volt mileage claim legit?

WARREN, Mich.--General Motors' announcement on Tuesday that it expects that the Chevy Volt will get an eye-popping 230 miles per gallon begs an obvious question: how can the mileage of electric vehicles be compared to gasoline cars?

It's a problem that the Environmental Protection Agency is working on with the Department of Energy, the Society of Auto Engineers, and California, an EPA representative said on Wednesday. But that system for testing mileage is still in development and not yet public.

The EPA also put out a statement on Tuesday saying that it has not tested the Volt for mileage yet and "cannot confirm the economy values claimed by GM." GM said that its mileage estimate, including triple digit combined city and highway driving, was based on a draft methodology developed by the EPA.

The lack of verifiable tests, however, hasn't stopped automakers from tantalizing consumers. The all-electric Nissan Leaf, due in late 2010, boasts the equivalent of 367 miles per gallon, and the electric Tesla Roadster claimed over 100 miles per gallon mileage as well.

Pressed on how mileage numbers for the Volt were arrived at, GM executives offered some details, saying that the number will vary depending on how far people drive before they replenish the car's batteries.

The draft EPA methodology figures that a plug-in electric vehicle driver will go a certain number of miles on batteries alone and then another portion on the gasoline engine, explained Frank Weber, the global vehicle line executive for the Chevy Volt. To arrive at the mix between battery versus gasoline, the EPA is studying average American driving patterns, executives said.

The EPA is also developing another, less familiar metric for electric vehicles. In the Volt's case, it will take 25 kilowatt-hours to go 100 miles. Weber said the models behind the EPA methodology are "robust," adding that he expects the EPA to disclose more about the tests later this year.

To come up with 230 miles per gallon for city driving, GM assumes that Volt owners charge the car's batteries once a day, which enables them to do the majority of their driving from electricity drawn from the socket. The Volt, due late next year, is designed to run 40 miles on electric charge and then use a gasoline engine to sustain the battery for longer trips.

Misleading? Triple digit combined fuel efficiency is certainly impressive--the Toyota Prius and Honda Insight hybrids both sport combined mileage of about 50 miles per gallon depending on driving style.

But immediately after GM's announcement, people began complaining that the claim is misleading.

… Read more

To grow, GM tries to make small cars cool

WARREN, Mich.--For all the attention on the electric Chevy Volt, General Motors has big expectations for another key car segment: small cars.

The auto giant opened up its design studios and testing grounds to the media on Tuesday to showcase its product pipeline of 25 new models over the coming two years. Having dramatically cut costs, its turnaround now rides on its ability to sell new cars.

Certainly, GM will continue to sell SUVs, trucks, and large sedans--highly profitable product categories that flourished when gasoline was cheaper than now. But GM's designers have sharpened their focus on smaller … Read more

Chevy Volt to pull 230 mpg in city

WARREN, Mich.--The gas-electric Chevy Volt will get triple-digit mileage, including an estimated 230 mpg for city driving, General Motors said Tuesday.

The 230 mpg--teased in a stealth advertising campaign on billboards and during baseball games--is based on a draft methodology for electric vehicles developed by the Environmental Protection Agency, GM CEO Fritz Henderson said here.

The struggling auto giant held a media event to offer an update on its product and technology plans as it tries to stimulate sales following a bankruptcy and restructuring that has left it 60 percent owned by the U.S. Treasury Department and 11 … Read more

Politicos give natural gas, efficiency top billing

Increasing domestic natural gas production and retrofitting buildings to be more efficient should form the basis of a low-carbon U.S. energy policy, according to a statement put out Monday during the Clean Energy Summit.

The summit, held for the second year in Las Vegas, brought together some of the most recognized political figures shaping energy policy, including Sen. Harry Reid of Nevada, Energy Secretary Steven Chu, and businessman T. Boone Pickens. Other speakers included Bill Clinton, Labor Secretary Hilda Solis, Al Gore, and green jobs advocate Van Jones.

The event was organized by the Center for American Progress and … Read more

Environmentally friendly toaster saves planet and breakfast

It's not always that the hottest trends in design coincide with the most efficient. When it comes to many modern appliances, however, energy efficiency has become a key criterion in comparing one to the next. Consumers have spoken, and what they're asking for are appliances that use their energy more effectively and reduce waste.

The trend has expanded to include even the simplest kitchen gadgets. Take this toaster by Morphy Richards, for instance: dubbed the 'Ecolectric," it promises an evenly browned slice of toast every time for an energy cost of 35 percent less.

The secret to … Read more

Mercedes debuts new, efficient, four-cylinder E-Class models

Mercedes-Benz has announced the addition of new four-cylinder E 200 CDI and CGI BlueEfficiency models to the European 2010 E-Class lineup.

The thrifty E 200 CDI is powered by a common-rail, direct-injected, 2.1-liter, diesel engine that outputs 136-horsepower and a staggering 365 pound-feet of torque. Zero to 62 mph happens in a decent 10.2 seconds, but what's most impressive is the 45.2 mpg that it averages while doing so.

Those who want a little bit more speed can hit 62 mph in 8.7 seconds in the E 200 CGI, which is powered by a turbocharged, … Read more

High-end desktop power test reveals hidden costs of PC gaming

If you're a PC gamer, you might willingly pay $15 a month to stomp around the World of Warcraft. What if we also told you that depending on your rig and daily play time, you might also be paying a hidden fee of $10 or more a month to play even single-player PC games?

After our debut round of all-in-one PC power efficiency results, we've had a chance to test the power consumption of a few other kinds of desktops. The most intriguing system so far has been a $3,600 gaming desktop from Digital Storm.

It's … Read more