From a technology development standpoint, Mike Lawson likens today’s wave energy industry to the wind industry in the 1970s or ’80s. There are tens—maybe hundreds—of concepts for wave energy converters (WEC) in various stages of development, but no single solution has been established as commercially viable yet.
Fortunately, coming of age in today’s renewable energy market has many benefits. Modern computer models and advanced engineering techniques are allowing WEC technologies to progress rapidly. Furthermore, anyone can be an innovative force in this emerging industry.
To support the growth of reliable and cost-effective technologies, the U.S. Department of Energy is funding the National Renewable Energy Laboratory (NREL) and Sandia National Laboratories (SNL) to produce a publicly available and open-source WEC simulation (WEC-Sim) capability. This tool will allow for the analysis and optimization of proof-of-concept and prototype WEC devices. Figure 1 shows the structure of the WEC-Sim code and Figure 2 presents an example of an oscillating-surge WEC device modeled with the WEC-Sim framework.
Although several commercial tools are capable of modelling WEC performance, these simulation programs can cost as much as $40,000 per year and are not easily customizable because the source code is proprietary.
NREL and SNL aim to provide open-source code that can run on a standard personal computer for the marine and hydrokinetic community. This tool would allow device manufacturers, project developers, government agencies, educational institutions, and nongovernment organizations to model the performance of promising new WEC ideas. “The modeling needs are rapidly evolving because so many new ideas are coming into development,” says Lawson. “The main benefit of the WEC-Sim program is that it can be modified to meet the needs of new devices.”
Now about 1 year into the 3-year effort, the NREL and Sandia team have an alpha version of the code that they are working with internally. They are verifying its functionality by modeling three devices that span the current design space of WEC solutions under development by industry. In addition to a floating two-body heaving point absorber and a surge-pitch device, the team will also run simulations with another device to be determined.
A beta version of the code will be released this coming June on the NREL, Sandia, OpenEI, and GitHub websites. At a time when the identity of the wave energy industry is coming into focus, WEC-Sim promises to help establish a level playing field among potential players.
“The industry has not converged on a leading WEC solution in this space yet,” says Michael. “It’s a different game. It is really an exciting time.”
For more information on: NREL