by: Yasmin Ajirniar
Universally recognized as an environmental concern and non-traditional international security issue via the United Nations Federation on Climate Change treaty, carbon dioxide emissions have drastically climbed, altered the atmosphere, acidified oceans, and driven the rising average global temperature. State governments, with the financial resources and the capital to enact and enforce far-reaching policies and programs, are well posed to address the causes and to mitigate the deleterious effects of climate change. So, how has the United States government taken that responsibility and reflected the will of many of its civilians?
The US Department of Energy, a cabinet-level agency, exercises jurisdiction over not only safety and handling nuclear material, and nuclear reactor production but also energy safety, policy, research and production. Underneath the Department of Energy’s oversight exists the Advanced Research Projects Agency-Energy (ARPA-E), a project that was conceived in 2007 after the National Academies issued a critical report: the United States was becoming less competitive in the science and technology surrounding energy. It is through ARPA-E that several programs have been created to increase the reliability, accessibility and production of cleaner energy; three exemplary programs include FOCUS, MOSAIC, and GENI.
Bridging the science of photovoltaics and concentrated solar power, the Full Spectrum Optimized Conversion and Utilization of Sunlight program, otherwise known as FOCUS, has been largely driven by research conducted at Arizona State University, where new solar cell designs produce both electricity and heat for immediate and sustained use. The current challenge behind photovoltaics (PV) is the limited utilization of solar energy since only direct, not diffuse, sunlight can be converted into electricity. A hybrid approach, through a silicon based solar cell coated with a dichoric optical film, improves the use of solar energy and enhances the output of the solar cell. While the solar cells transform solar energy, reflected light is concentrated at a thermal absorber, generating heat which is carried via flowing oil to a steam turbine.
The Micro-scale Optimized Solar-cell Arrays with Integrated Concentration program, or MOSAIC, also addresses the limitations imposed on PVs and also on CSPs in that they both require direct sunlight to operate. Therefore, they are well suited to be installed in the United States’ southwest but are not effective in other regions. Further, incorporating these solar cells onto existing structures is often difficult given the size demands of these solar cells to be operational. The rooftops of buildings, if not sturdy enough, will not sustain the weight and bulk of large solar cells. Here, MOSAIC seeks to expand the application of solar cells by developing micro-scale cells that can be utilized by a larger community.
Lastly, the Green Electricity Network Integration initiative recognizes the backend of the renewable energy production and consumption, the transfer of electricity from facilities to businesses and residences. Consider the following: nearly one-tenth of electrical energy is lost in transmission while electricity contributed to 27.5% of the United States’ CO2 emissions. The electrical grids which currently supply energy demands in the United States require immediate attention, especially with 30% of the hardware near expiration. An out-dated electrical network is not only vulnerable to power outages and foreign attacks but also it also limited in the renewable energy it can supply, despite the fact that solar energy has no associated emissions. With improved hardware, computing and communications, the electrical network can achieve greater efficiency, reliability, power flow control and significantly greater integration of renewable energy.