Abstract
We present an in-depth analysis of the theoretical variability of riverine hydrokinetic energy resources across 18 Hydrologic Units (HUs) within the Contiguous United States (CONUS) and provide high-fidelity information on the available U.S. riverine hydrokinetic resources for industry stakeholder, including energy planners, industry project developers and researchers. We update and expand upon previous assessments by the Electric Power Research Institute (EPRI) in 2012 to enable a more comprehensive understanding of the spatiotemporal distribution and a more refined estimate of the magnitude of the CONUS theoretical resources and its uncertainty.
Using the hourly flowrate data of National Water Model Retrospective V2.1 (NWMv2.1) spanning 42 years (February 1979- December 2020) and employing a finer 10-m National Elevation Dataset (NED) in National Hydrography Dataset Plus V2 (NHDPlusV2), our approach marks a significant methodological advancement over the earlier assessment, which relied on mean annual flowrate and a 30-m NED in NHDPlusV1. Following the International Electrotechnical Commission (IEC) energy resource assessment standards (IEC TS 62600-301), the weighted average of flowrate in different time intervals (monthly, annual, and interval-wise) are calculated with CDF histogram across 75 bins. The weighted average flowrate is used to obtain the monthly, annual, and interval-wise (January 1980 – December 2020) distribution of theoretical power and annual energy production (AEP) by each HU. Interannual and seasonal variability is also presented to determine where the energy is spread more evenly throughout the year or concentrated within a certain period. The correlations between hydrokinetic energy and monthly/annual precipitation patterns across HUs are identified, and the uncertainty of our theoretical resource estimates quantified. This thorough analysis can be used by energy planners and project developers for reconnaissance and feasibility studies and project planning.
A significant finding of our study is a 30% increase in the total CONUS riverine hydrokinetic energy resource compared to the previous assessment. This improvement stems from utilizing a longer dataset, hourly flowrate, and higher-resolution elevation dataset and including all flowline segments, not just those exceeding a flowrate of 1000 cfs. Furthermore, it should be underscored that hydrokinetic energy resource assessments' enhanced accuracy and reliability can be achieved through updated methodologies and datasets, offering valuable insights for developing and optimizing sustainable energy solutions.