According to Kwabena Boahen, a computer scientist at Stanford University, a robot with a processor as smart as the human brain would require at least 10 megawatts to operate. That’s the amount of energy produced by a small hydroelectric plant. But a small group of computer scientists may have hit on a new neural supercomputer that could someday emulate the human brain’s low energy requirements of just 20 watts–barely enough to run a dim light bulb….[The new idea] trades the extreme precision of digital transistors for the brain’s chaos of many neurons firing, with misfires 30 percent to 90 percent of the time. Yet the brain works with this messy system by relying on crowds of neurons to shout over the noise of misfires and competing signals.
That willingness to give up precision for chaos could lead to a new era of creative computing that simulates the unpredictable patterns of brain activity. It could also represent a far more energy-efficient era — the Neurogrid fits in a briefcase and runs on what amounts to a few D batteries, or less than a watt. Rather than transistors, it uses capacitors that get the same voltage of neurons.
Much more here.