Author(s): Katelyn Kirby; Colin Rennie; Ioan Nistor; Julien Cousineau; Sean Ferguson
Keywords: Riverine hydrokinetic energy; Hydrodynamic numerical model; River flow measurements; Renewable power assessment; Acoustic doppler current profiler
Abstract: Background: Hydrokinetic energy extraction uses the velocity of naturally moving water to turn a turbine to generate renewable electricity. The amount of hydrokinetic energy available is proportional to the cube of the velocity of the water. Because the amount of hydrokinetic energy is heavily dependant on the velocity of the flow, the flow condition of the river is expected to greatly influence the amount of hydrokinetic energy available for extraction, although this has not been explicitly tested before. To characterize the influence of flow condition on the available energy, the International Electrotechnical Commission (IEC) recommended using a 15-point velocity duration curve (VDC) based on 10 years of available data or modelled data with less than 5% calibration error (IEC 2019). So far, no studies have met these standards, likely because the IEC standards were produced in response to the inconsistencies in the published methods at that time. For example, Nordino et al. (2016) generated a VDC from 5 years of discharge data, Holanda et al. (2017) considered maximum, minimum, and mean discharge conditions, and Kasman et al. (2019) used five years of discharge data to develop their simulation. Other studies, such as Petrie et al. (2014), Kalnacs et al. (2014), Filizola et al. (2015), and Montoya Ramírez, et al. (2016) did not consider seasonal variation of flow at all in their assessments of hydrokinetic energy potential. By not considering the complexities of hydrokinetic energy availability across the river reach, it may limit the meaningfulness and practicality of these studys’ findings. Objectives: This research aims to understand the influence of flow conditions on hydrokinetic energy potential in a river by considering the 2D velocity flow field, rather than a typical single per-reach average velocity value. The goal is to explore the impact that flow condition consideration and spatially dense bathymetry and velocity measurements can have on the findings of hydrokinetic energy assessments. This will be done by utilizing data collected on two different dates (November 5, 2020 and June 4, 2021) under two different flow conditions to model a reach of the Rouge River, QC under additional flow conditions. Novelty: These types of hydrokinetic assessments are on the rise in popularity, but methods have been inconsistent with some only considering average velocity, some taking cross-sectional velocity measurements, some utilizing spatially intense data. This is the first study to consider the 2D velocity flow field in a reach under multiple flow conditions to estimate and analyze the hydrokinetic energy potential. Additionally, because hydrokinetic energy assessments are relatively new, there is a gap in understanding of best practices for defining the feasibility of energy extraction for a reach and quantification of available energy. Bibliography: References have not been included for space considerations.