Google has announced the Little Box challenge: a contest that will pay you $1 million if you build a 95% energy efficient power inverter, no bigger than a tablet, that’s capable of powering a house. A power inverter is a box that turns direct current that flows from solar panels or batteries, to alternating current that can be used to power appliances in your home. Current electricity inverters are around the size of a cooler. Google thinks that the sizes of current inverters are a main barrier keeping solar from widespread adoption. Smaller inverters will make installations of solar easier and could push solar into the mainstream. So let’s start brain storming…