There has been an enormous growth in national and state-level voluntary campus sustainability programs in the U.S. in recent years. These programs not only help universities and colleges institutionalize sustainability principles into everyday processes and actions, but also create a common knowledge pool of resources and best practices that enable these institutions to build strong sustainable communities.
Scientists at the California Institute of Technology have developed a new type of solar cell that comprise of arrays of thin silicon wires embedded in polymer substrate. The unique optical interactions between these wires provide the cells with an enhanced light absorption capability and improved internal quantum efficiency over conventional solar cells. These new cells are much cheaper to produce on account of the very low amounts of silicon needed to build them. The superior structural flexibility possessed by the silicon wire array solar cells is expected to further reduce their production cost since they can be produced using a lower-cost process.
This country’s 130 million homes together generate more than 20% of the nation’s carbon dioxide greenhouse gas emissions. This is one of the most significant contributing sources in the country to global warming. Existing techniques and technologies in energy efficiency retrofitting can reduce home energy use by up to 40 percent per home on average which would also lower our national greenhouse gas emissions by 160 million metric tons annually by the year 2020. In addition doing so would reduce home energy bills by $21 billion a year and over time these savings would more than pay for the high up-front costs for energy efficiency retrofitting.
Green roofs, green walls, green parking lots, shade trees, the greening of urban spaces in general, the restoration of urban waterways, wetlands and the re-greening of brownfield areas; can all be thought of as different techniques to nurture a green living skin over regions of urban development. While there are many important differences between each of these separate techniques as well as their underlying technologies they all share a common overarching goal of bringing an analog of the natural living green skin that characterizes the natural landscape back into our urban areas. They all promote the restoration and re-integration of these heavily populated areas back into the surrounding natural environment.
