GEF

Unit 9  |  New Technology and Innovative Sustainability Approaches 192 Entrepreneurs and engineers are exploring a wide range of innovative approaches to energy that may allow renewable sources to become much more widespread. Hyper Solar, a California-based company, uses nanoparticles that capture sunlight to generate hydrogen gas, which is then combined with CO 2 from power plant emissions to produce methane (CH 4 ). This is a sort of renewable natural gas that can be used instead of fossil natural gas to generate electricity, heat build- ings, or power vehicles. Another innovative company in California is Nanosolar. Nanosolar is revolutionizing the production of photovolta- ics by using an efficient printer-like process to make sheets of solar cells that use CIGS (Copper, Indium, Gallium, Selenium) instead of silicon. This process significantly lowers production costs over standard methods. Wind, solar, and other renewable energy is intermittent , and requires a method of storage for use when the source is not available. Renewable energy storage and transfer has created some of the greatest roadblocks for widespread use. Currently, storage technology is undergoing dramatic innovations, mak- ing these sources more viable. U.K.-based Isentropic is creating highly efficient energy stor- age devices that transfer heat between two large containers of gravel. Ice can even be used as a storage medium, an approach taken by California-based Ice Energy. In their sys- tem, air conditioners freeze water at night when electricity is cheapest, and then use air circulated over the ice to cool buildings during the day. Many experts maintain that solving storage challenges represents the last barrier to widespread adoption of renewable energy. NANOPARTICLE A microscopic particle of matter that is measured on the nanoscale, usually one that measures less than 100 nanometers. INTERMITTENT Occurring at irregular intervals; not continuous or steady.