Hello,

We noticed you're browsing in private or incognito mode.

To continue reading this article, please exit incognito mode or log in.

Not an Insider? Subscribe now for unlimited access to online articles.

Sustainable Energy

Novel Circuit Shrinks Laptop Chargers, Could Improve Appliance Efficiency

A new kind of power adapter is barely bigger than a plug.

Making power conversion devices smaller and cheaper would make them more convenient and help save energy.

A startup called FINsix has developed laptop power adapters that are 75 percent smaller than their conventional counterparts. The technology employed could also be used to improve the efficiency of a wide variety of devices and appliances, including washing machines and air conditioners.

FINsix’s first product, which the company will unveil next month at the Consumer Electronics Show in Las Vegas, replaces a conventional charging brick with a device just a little bigger than an ordinary plug. The 65-watt power adapter—which delivers more power than many laptops use—can charge multiple devices at once. It will be available by the middle of next year.

The power adapter is the first commercial application of a novel circuit design developed by David Perreault, a professor of electrical engineering and computer science at MIT (see “Power Electronics to Improve Computer Efficiency” and “Efficiency Breakthrough Promises Smartphones That Use Half the Power”).

FINsix’s power adapter is an after-market charger that can work with a variety of laptops and other devices. The company is also working with a laptop manufacturer to produce a dedicated charger. The power adapter has the potential to be far cheaper than conventional ones, because it’s smaller, it’s simpler to manufacture, and it uses far less material.

In addition to shrinking power adapters, the new circuit design could reduce the size and cost of a variety of devices known collectively as power electronics. These devices manipulate electricity, changing properties such as voltage and converting between AC and DC power; they can precisely control the power that goes to electric motors and compressors. Better power electronics can improve the efficiency of, say, household air conditioners, but they typically aren’t used in such applications because of their high cost.

FINsix’s technology shrinks power electronics by increasing the frequency at which these devices operate. The higher the frequency, the smaller the device can be. But ordinarily, higher frequencies also reduce efficiency.

The researchers at MIT and FINsix developed a way to recycle much of the energy that’s normally lost inside a power adapter, improving efficiency and making it practical to use frequencies 1,000 times higher than those used in conventional power adapters. “The rest of the field is making incremental changes and getting diminishing returns,” says Charles Sullivan, a professor of engineering at Dartmouth, who is not involved with the company. But FINsix, he says, is “leaping past that barrier.”

Other academic researchers and companies are working to shrink the size of power electronics by turning to new materials, such as gallium nitride, that can operate more efficiently at high frequencies than the silicon semiconductor materials used now (see “Eliminating the Laptop Charging Brick”). But the new materials can be expensive and are limited to specialty applications. As these materials get cheaper and are more widely adopted, FINsix’s technology could be used in conjunction with them to make power electronics even smaller and more efficient.

Tech Obsessive?
Become an Insider to get the story behind the story — and before anyone else.

Subscribe today

Uh oh–you've read all of your free articles for this month.

Insider Premium
$179.95/yr US PRICE

More from Sustainable Energy

Can we sustainably provide food, water, and energy to a growing population during a climate crisis?

Want more award-winning journalism? Subscribe to Insider Premium.
  • Insider Premium {! insider.prices.premium !}*

    {! insider.display.menuOptionsLabel !}

    Our award winning magazine, unlimited access to our story archive, special discounts to MIT Technology Review Events, and exclusive content.

    See details+

    What's Included

    Bimonthly magazine delivery and unlimited 24/7 access to MIT Technology Review’s website

    The Download: our daily newsletter of what's important in technology and innovation

    Access to the magazine PDF archive—thousands of articles going back to 1899 at your fingertips

    Special discounts to select partner offerings

    Discount to MIT Technology Review events

    Ad-free web experience

    First Look: exclusive early access to important stories, before they’re available to anyone else

    Insider Conversations: listen in on in-depth calls between our editors and today’s thought leaders

/
You've read all of your free articles this month. This is your last free article this month. You've read of free articles this month. or  for unlimited online access.