Browsing by Subject "Power plants"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Energy transitions on the Hawaiian Islands : water resources implications for Hawaii's electrical power system(2014-08) Dawes, Colleen Marie; Pierce, Suzanne Alise, 1969-; King, Carey; Beach, FredImported fossil fuels currently supply over 90% of the Hawaiian Islands' annual consumed electricity, the majority of which is produced by petroleum-fired power plants. The state of Hawaii has a goal to dramatically reduce this reliance on imports and achieve 30% locally sourced, renewable power use by 2030. This goal signals an energy transition for the state that is achievable through decommissioning, repurposing and new development in power generating technologies and infrastructure. In addition to dependencies on imports and fossil fuels, Hawaii's electrical industry is also currently the largest water user in the state of Hawaii with over 75% of all surface water and groundwater withdrawals attributed to thermoelectric generation and cooling. Transitions in Hawaii's fuel mix from a petroleum dominant mix to renewable fuel for power generation could have significant impacts on water use and availability: a small change in energy resources could mean significant changes in water use. Integrated planning and management for these two resources is needed. A successful energy transition for Hawaii in the next 15 years will involve precise planning, and strategic decision-making for both energy and water. This research adopts a systems view to evaluate energy-water interdependencies within Hawaii's electrical system, comparing the current fuel mix and projections for energy trends on the islands with the continental United States. A power plant database built from Hawaii-specific utility-scale data combined with national averages for thermoelectric water use reported in the literature provide an overview of Hawaii’s current electrical sector and its water use. This snapshot identifies critical resource management needs and reveals disparities between the electrically detached islands. Scenario analysis of projected change in Hawaii’s electrical sector is used to assess the implications for water use intensity across a range of locally sourced power capacity and generation options. Results indicate that, because it displaces petroleum power production, increases in renewable energies on Hawaii will produce substantial water savings, especially in total operational water withdrawals.Item Mitigating the impacts of droughts and heat waves at thermoelectric power plants in the United States(2014-12) Cook, Margaret Allison; Webber, Michael E., 1971-Recent droughts and heat waves have revealed the vulnerability of some power plants to effects from higher temperature intake water for cooling. Climate projections estimate higher air temperatures in future years, indicating that these problems could increase. This research seeks to understand the magnitude of influence that higher temperatures will have on power plant effluent water temperatures to quantify a power plant's exposure to risk of de-rating induced by low or warm cooling water availability. The objective of this analysis is to help policymakers and plant operators plan for future electricity supplies without damaging the natural environment of the cooling reservoirs and rivers. This objective is met via assessment of water constraints associated with current technology, policy, and environmental conditions in two river basins, the Gulf Coast Basin in Texas and the Upper Mississippi River Basin in the Midwestern United States. Risk of reduced operations at these power plants associated with thermal discharge limits is then assessed by estimating intake and effluent water temperatures and comparing these estimates to current restrictions. Of the thirty-three plants analyzed, none are estimated to exceed effluent temperature limits within the study period of 2015 to 2035. However, twelve power plants could face increasing intake temperatures, leading to potential issues with cooling efficiency. Fourteen plants could discharge slightly higher effluent temperatures, possibly influencing the ecosystem of the return water body upon discharge beyond today's impacts. To help with planning for future issues, this analysis also identifies many of the ways by which power plants mitigate issues with low water levels and high temperatures. Designing plants for potentially scarce water resources and making policies that protect water supplies and support energy resources could be beneficial in coming years. This research is intended to inform that objective.