The world's population has just hit 7 billion people and continues to grow. Population experts are concerned about the rise in consumption that will accompany the increase in people. One California home builder, ZETA Communities, designs and builds small, highly energy-efficient homes.
A pair of tweezers holds a graphene transistor fabricated on a silicon wafer. An I-Corps team from the University of Pennsylvania is working on scaling up their cheaper method of making high-quality graphene, an extremely strong, conductive material one atom thick that was the subject of a Nobel Prize last year.
A worker stands next to an array of Sharp solar cell modules at a power plant south of Tokyo in August. Sharp was one of 1,400 solar panel manufacturers in attendance at the Solar Power International conference, where industry optimism was high.