Most Wave Energy Conversion device-types have undergone some fundamental development and optimization. However, most developments focus on a sub-set of relevant device characteristics such as device performance, without a view on the cost impact of performance-enhancing measures. This approach leads to sub-optimal solutions most of the time and oftentimes fails to identify the optimal design configuration.
A paradigm shift occurs once integrated design methods are applied to the device development process to identify the major cost-drivers and then finding an optimal configuration within a parametric space. These design-spiral approaches tend to be significantly more cost-effective than more linear approaches. However, they do require the appropriate utilization of a wide range of numerical methods and parametric costing tools.
In this paper we present a framework for the techno-economic optimization of a deep-water oscillating water column device. Economic analysis of the baseline device has shown that the levelized cost of electricity from this type of technology is largely driven by structural costs of the hull itself, which was targeted to reduce the cost of electricity from this technology.
To optimize the overall device envelope, all tools had to be setup to allow for rapid parametric variation of dimensions to allow an efficient optimization process to unfold. Models setup included: (1) A parametrically driven performance model, (2) a parametrically driven structural model, (3) an extreme loads model to provide inputs to the structural model, and (4) a parametrically driven cost model. An appropriate economic model was setup to allow for the determination of the Levelized Cost of Electricity (LCoE) for each design iteration studied.
Once these models were setup and validated using appropriate wave tank testing methods, an iterative design-spiral approach was used to systematically identify the lowest-cost design configurations.
This project clearly demonstrated that significant material and cost-reductions are attainable using a carefully designed structural optimization process that is guided by an intelligent techno-economic optimization process. It also demonstrates that for certain structures, FRP may be an economically competitive option at commercial unit scale.