A techno-economic approach to wave energy resource assessment and development site identification

Abstract

A careful and detailed wave resource assessment is essential for identification of a successful wave energy project. However, current approaches inherently limit application to specific locations and wave energy converter architectures, rather than providing for broad application across the industry. Generally, a site is identified based on either the gross resources, or an assessment of minimal conflict with current ocean users. This chosen location defines the wave characteristics and a specific Wave Energy Converter (WEC) technology is identified. The predetermined wave characteristics and associated device performance then determine the final power production. This is a ‘bottom-up’ type approach. The current work introduces a novel ‘top-down’ approach. The new approach incorporates a novel device-agnostic performance constraints and economic considerations to identify priority development sites over broad coastal regions. The technological constraints are represented by frequency and directional screening functions, derived from the power matrices of four conceptually distinct WEC devices. This screening process estimates the extractable portion of the wave resource. Subsequently, a Net Revenue Index (NRI) is developed that characterizes the economic potential based on proximity to existing electricity markets and site-specific installation costs. Hot-spots are identified based on the screened extractable resource and economic analyses to represent both long and short term development opportunities. This ‘top-down’ approach is demonstrated through a case study of the West Coast of Vancouver Island. For both the screened wave resource and NRI data, hot-spots formed from locations exhibiting values in the 90th percentiles are identified. If fully developed, the resource hot spots potential is ~67,000 GWh of annual energy delivery, while hot-spots based on NRI represent economic hot-spots present 21,000 GWh of annual energy delivery. Intersecting the two collections of hot-spots results in 336 km2 with an average of wave energy flux of 35 kW/m.