Search All of Tethys Engineering

In order to promote and support development of the wave energy industry, Sandia National Laboratories (SNL) has developed a Wave Energy Development Roadmap. The Wave Energy Development Roadmap outlines the pathway from initial design to commercialization for Wave Energy Converter (WEC) technologies. Commercialization of a wave energy technology is embodied in the deployment of an array of WEC'…

This paper details the development and validation of a numerical model of the Wavestar wave energy converter (WEC) developed in WEC-Sim. This numerical model was developed in support of the WEC Control Competition (WECCCOMP), a competition with the objective of maximizing WEC performance over costs through innovative control strategies. WECCCOMP has two stages: numerical implementation of…

This numerical study compares the wave field generated by the spectral wave action balance code, SNL-SWAN, to the linear-wave boundary-element method (BEM) code, WAMIT. The objective of this study is to assess the performance of SNL-SWAN for modeling wave field effects produced by individual wave energy converters (WECs) and wave farms comprising multiple WECs by comparing results from SNL-…

Coastal communities face unique challenges in maintaining continuous service from critical infrastructure. This research advances capabilities for evaluating the impact of using wave energy to desalinate water on the resilience of coastal communities. The study focuses on the feasibility of using wave energy conversion to provide drinking water to communities in need and applying resilience…

The floating oscillating surge wave energy converter (FOSWEC) is a wave energy converter that was designed, built, and tested to develop an open-access data set for the purpose of numerical model validation. This paper details the experimental testing of the 1:33-scale FOSWEC in a directional wave basin, and compares experimental data to numerical simulations using the wave energy converter…

This paper illustrates the status of wave energy development in Pacific rim countries by characterizing the available resource and introducing the region's current and potential future leaders in wave energy converter development. It also describes the existing licensing and permitting process as well as potential environmental concerns. Capabilities of Pacific Ocean testing facilities are…

The Wave Energy Converter Simulator (WEC-Sim) is an open-source code jointly developed by Sandia National Laboratories and the National Renewable Energy Laboratory. It is used to model wave energy converters subjected to operational and extreme waves. In order for the WEC-Sim code to be beneficial to the wave energy community, code verification and physical model validation is necessary. This…

In this paper we provide an update on the status of the WEC-Sim project, both the code development and experimental testing efforts. Code development has been focused on adding features that improve the delity of the simulation including non-linear hydrostatic and excitation forces calculation, body-to-body interactions through coupled radiation forces, Morison drag, and more direct modeling…

In 2013 the National Renewable Energy Laboratory (NREL) and Sandia National Laboratories (SNL) initiated the WEC-Sim project with the objective of developing a verified and validated open-source wave energy converter (WEC) simulation tool to promote and support the wave energy industry and research community. To achieve this objective, NREL and SNL identified three main tasks. (1) Develop WEC-…

The National Renewable Energy Laboratory (NREL) and Sandia National Laboratories (SNL) have developed WEC-Sim to provide the wave energy converter (WEC) design community with an open-source simulation tool. WEC-Sim models the system dynamics of WEC devices using multibody dynamics methods and simulates hydrodynamic forces using coefficients predicted from potential flow models. In this paper…

This study evaluates the accuracy of using the opensource wave energy converter modeling WEC-Sim code to model an oscillating water column (OWC) as a virtual point absorber. WEC-Sim is a free, open-source hydrodynamic modeling extension of MATLAB/Simulink, and is designed primarily for ease of use and the modeling of oscillating body wave energy converters (e.g., point absorbers). Oscillating…

On behalf of Ocean Energy Systems (OES) and the US Department of Energy, the PRIMRE (Portal and Repository for Information on Marine Renewable Energy) team held an international workshop to explore the potential for sharing data on marine energy. The workshop was held online, hosted by the three US national laboratories that make up the PRIMRE team [Pacific Northwest National Laboratory (PNNL…

WEC-Sim (Wave Energy Converter SIMulator) is an open-source code for simulating wave energy converters, jointly developed by National Renewable Energy Laboratory and Sandia laboratories in the United States. WEC-Sim is developed in MATLAB/SIMULINK with Simscape Multibody, which solves the multi-body dynamics of the system. A brief overview on the methodology and the capability of the WEC-Sim…

The Marine Renewable Energy (MRE) industry is in the early stages of development corresponding to low technology readiness levels (TRLs) where the ability of the MRE community (developers, researchers, academics, stakeholders, investors, and regulators) to work together to share knowledge, experience, and lessons learned is critical to the advancement of the entire MRE industry. Through…

In the wave energy industry, there is a need for open source numerical codes and publicly available experimental data, both of which are being addressed through the development of WEC-Sim by Sandia National Laboratories and the National Renewable Energy Laboratory (NREL). WEC-Sim is an open source code used to model wave energy converters (WECs) when subject to incident waves. In order for the…

WEC-Sim (Wave Energy Converter-SIMulator) is an open-source wave energy converter (WEC) code capable of simulating WECs of arbitrary device geometry subject to operational waves. The code is developed in MATLAB/Simulink using the multi-body dynamics solver SimMechanics, and relies on Boundary Element Method (BEM) codes to obtain hydrodynamic coefficients such as added mass, radiation damping,…

Wave energy converters (WECs) are commonly designed and analyzed using numerical models that combine multibody dynamics with hydrodynamic models based on the Cummins equation and linearized hydrodynamic coefficients. These modeling methods are attractive design tools because they are computationally inexpensive and do not require the use of high-performance computing resources necessitated by…

The field of marine and hydrokinetic energy(or marine renewable energy) includes technologies used to convert the energy of waves, tides, currents and ocean thermal gradients primarily into electricity. Compared to traditional energy generation sources, and more established renewables (such as wind and solar), marine and hydrokinetic energy is in the early stages of development(corresponding…

To promote and support the wave energy industry, a wave energy converter (WEC) design tool, WEC-Sim, is being developed by Sandia National Laboratories and the National Renewable Energy Laboratory. In this paper, the WEC-Sim code is used to model a point absorber WEC designed by the U.S. Department of Energy's reference model project. Preliminary…

The sharing of knowledge, experience, and lessons learned facilitates solving common problems and accelerating the development of the MRE industry. In order to increase the dissemination of such information, the US Department of Energy, through its national laboratories has engaged the international MRE community to understand online information needs. Six thematic needs were determined:…