Transphorm Looks To Save Lost AC/DC Energy

It's a fact of physics: There's AC and there's DC. And in the process of converting

electricity from one form to the other - going from the AC power that comes out of the

wall socket to the DC power that runs your laptop, for instance - significant energy is

lost. Maybe as much as 10 percent. How to overcome this waste? Use gallium nitride

instead of silicon in the power conversion modules. That's the solution that Google

Ventures, Kleiner Perkins Caufield & Byers and other investors are betting $38 million

on, backing a startup called Transphorm.

Transphorm says it has optimized gallium nitride for power electronics and "has

developed novel devices such as transistors, circuits, and complete modules that

include all the components needed to replace conventional systems," according to MIT's

Technology Review.

"The impact is huge - on the grid, on the planet," Tranphorm chief Umesh Mishra said at

an event at Google headquarters, according to the San Francisco Chronicle. "Whenever

you use electrical energy, you're paying a hidden tax due to the inefficiencies of

power conversion."

The Transphorm technology would also work, of course, in the other direction: energy

stored in battery packs in electric vehicles like the Nissan Leaf has to be converted

to AC to run the motor, and solar power systems use inverters to turn DC power into AC

for household use. Gallium nitride would help make those systems 90 percent more

efficient - and lighter and less bulky - Transphorm says. Those brick-like laptop

adapters might finally be a thing of the past.

As good as this all sounds, Grist's Todd Woody notes that long design cycles could mean

that even if everything Transphorm says is true, gallium nitride will arrive slowly in

devices. And as with most new technologies, gallium nitride modules are likely to be

expensive until volume ramps up.