Inverters are sort of the nerve-center of a solar power array, they convert the DC solar power produced by the solar panels into the AC solar power used well, just about everywhere. But inverters are still big and clunky and while costs have come down they haven’t come down like the costs of solar panels have. That’s why Google and IEEE (Institute of Electrical and Electronics Engineers) introduced the $1 million Little Box Challenge in May to build a better, smaller inverter—one that’s about a tenth of the size of current inverters.
While micro-inverters can convert DC into AC on the module level they don’t provide enough energy density to convert the power from multiple modules while retaining their small size. Hence most systems use an inverter, which Google said is the size of a cooler.
“We want to shrink it down to the size of a small laptop, roughly 1/10th of its current size,” Google said on its official blog. “Put a little more technically, we’re looking for someone to build a kW-scale inverter with a power density greater than 50W per cubic inch. Do it best and we’ll give you a million bucks.”
Google explained its reasoning thusly: “A smaller inverter could help create low-cost micro-grids in remote parts of the world. Or allow you to keep the lights on during a blackout via your electric car’s battery. Or enable advances we haven’t even thought of yet.”
IEEE aded that such advances in solar inverter design could lead to higher efficiency, increased reliability, and lower energy costs from renewable energy like solar power.
“We are very pleased to present this important initiative together with Google to encourage innovation. By participating in this challenge, members of industry and academia can play a pivotal role in a technological innovation that could have a major impact on the world,” said IEEE President Don Tan.
Google also pointed people to some potential strategies. “Some recent advances may change what’s possible in power electronics. For example, Wide-bandgap (WBG) semiconductors—such as gallium-nitride (GaN) and silicon-carbide (SiC)—not only enable higher power densities than conventional silicon-based devices do, but can also convert between DC and AC at higher temperatures, using higher switching frequencies, and with greater efficiency,” said Maggie Johnson, Google’s Director of Education and University Relations.
People and universities can register for the challenge at www.littleboxchallenge.com and have to register by Sept. 30, 2014.