An increase in population and need to protect the planet has created many initiatives and research goals in developing alternatives methods of fueling. Federal and state policies have provided a push for industries to find ways to of reducing their impact on the environment while maintaining competitiveness. In the sector of alternative fuels, large policies such as the Renewable Fuel Standards (RFS) in the United States are making goals to reduce vehicular fuel from coal and oil, and focus on alternative fuels such as ethanol and biodiesel. Along with the RFS and other federal policies, states are introducing independent initiatives to promote the use of alternative fuels.
Research has shown that other crops besides corn can feasibly be used to produce ethanol for fuel use. One of the major crops of interest currently is switchgrass (Panicum Virgatum L.) because of its ability to grow under a variety of weather conditions and soil types. Switchgrass does not require as much maintenance as corn and is a perennial grass that can have high yielding fields for up to 9 years.
This report focuses on the impacts from using switchgrass-derived ethanol to meet the state of Arizona’s policy to have government fleet vehicles operating on alternative fuels. The study uses a life cycle assessment (LCA) approach to evaluate 22 million gallons of ethanol produced in Arizona and stored at fueling stations for use. Impacts in land use, global warming, and water quality are evaluated using software tools and databases in Ecoinvent and Simapro.
The results of the study indicate that the cultivation and harvest phase of the process will contribute the most to negative environmental impacts. According to the study, application of heavy nutrient fertilizer and the machinery needed for the additional agriculture have the potential to contribute over 36 million moles of hydrogen and 89 million CTU eq. to the air, soil, and water.
The City of Phoenix has committed to public transit improvements in the Transportation 2050 plan and has recently adopted a Complete Streets Policy. Proposed changes include mobility improvements and creating a safe and comfortable environment for non-motorized road participants. To understand what kind of improvements would benefit thermal comfort the most, it is necessary to understand heat exposure at finer spatial scales, explore whether current bus shelter designs are adequate in mitigating heat-health effects, and comprehensively assess the impact of design on physical, psychological and behavioral aspects of thermal comfort. A study conducted at bus stops in one Phoenix neighborhood examined grey and green infrastructure types preferred for cooling and found relationships between perception of pleasantness and thermal sensation votes. Walking interviews conducted in another neighborhood event examined the applicability of a framework for walking behavior under the stress of heat, and how differences between the streets affected perceptions of the walkers. The interviews revealed that many of the structural themes from the framework of walking behavior were applicable, however, participants assessed the majority of the elements in their walk from a heat mitigation perspective. Finally, guiding questions for walkability in hot and arid climates were developed based on the literature review and results from the empirical studies. This dissertation contributes to filling the gap between walkability and outdoor thermal comfort, and presents methodology and findings that can be useful to address walkability and outdoor thermal comfort in the world’s hot cities as well as those in temperate climates that may face similar climate challenges in the future as the planet warms.
Climate change could significantly affect consumer demand for energy in buildings, as changing temperatures may alter heating and cooling loads. Warming climates could also lead to the increased adoption and use of cooling technologies in buildings. We assess residential electricity and natural gas demand in Los Angeles, California under multiple climate change projections and investigate the potential for energy efficiency to offset increased demand. We calibrate residential energy use against metered data, accounting for differences in building materials and appliances. Under temperature increases, we find that without policy intervention, residential electricity demand could increase by as much as 41–87% between 2020 and 2060. However, aggressive policies aimed at upgrading heating/cooling systems and appliances could result in electricity use increases as low as 28%, potentially avoiding the installation of new generation capacity. We therefore recommend aggressive energy efficiency, in combination with low-carbon generation sources, to offset projected increases in residential energy demand.
Study Background: Researchers at ASU have determined that significant energy and environmental benefits are possible in the Phoenix metro area over the next 60 years from transit-oriented development along the current Valley Metro light rail line. The team evaluated infill densification outcomes when vacant lots and some dedicated surface parking lots are repurposed for residential development. Life cycle building (construction, use, and energy production) and transportation (manufacturing, operation, and energy production) changes were included and energy use and greenhouse gas emissions were evaluated in addition to the potential for respiratory impacts and smog formation. All light rail infill scenarios are compared against new single family home construction in outlying areas.
Overview of Results: In the most conservative scenario, the Phoenix area can place 2,200 homes near light rail and achieve 9-15% reductions in energy use and emissions. By allowing multi-family apartments to fill vacant lots, 12,000 new dwelling units can be infilled achieving a 28-42% reduction. When surface lots are developed in addition to vacant lots then multi-family apartment buildings around light rail can deliver 30-46% energy and environmental reductions. These reductions occur even after new trains are put into operation to meet the increased demand.
Building energy assessment often focuses on the use of electricity and natural gas during the use phase of a structure while ignoring the energy investments necessary to construct the facility. This research develops a methodology for quantifying the “embedded” energy and greenhouse gases (GHG) in the building infrastructure of an entire metropolitan region. “Embedded” energy and GHGs refer to the energy necessary to manufacture materials and construct the infrastructure. Using these methods, a case study is developed for Los Angeles County.