Last week the U.S. Department of Energy (DOE) announced its investment of $74 million "for 63 projects to research, develop, and test energy-efficient and flexible building technologies, systems, and construction practices to improve the energy performance of our Nation's buildings and electric grid."

The investment comes in light of the fact that America's buildings use more energy than any other sector in the country, making up 40 percent of total energy use and almost 75 percent of the nation's electricity consumption.

"DOE is accelerating its quest to improve the energy productivity and flexibility of America’s residential and commercial buildings," said Assistant Secretary of Energy Efficiency and Renewable Energy Daniel R Simmons in a statement. "We’re renewing our commitment to develop state-of-the-art building technologies that will empower Americans with more options to enhance buildings performance quickly without disruption to their lives."