A free tool developed at the U.S. National Renewable Energy Laboratory (NREL) will enable designers of wave energy converters (WECs) to obtain baseline information about the performance of different WEC systems in various ocean settings. The system allows users to explore and compare small WEC performance by visualizing WEC data.

The Small WEC Analysis tool uses performance data from downscaled models of common WEC devices and their calculated performance outputs. The tool streamlines the comparison of these common WEC models:

• Attenuators — multisegment devices that float parallel to ocean waves and rise and fall, creating a flexing motion that drives turbine rotation or a hydraulic pump
• Oscillating surge WECs — devices that have a vertical flap affixed to the seabed, which generates energy from the back-and-forth motion of waves
• Single-body point absorbers — simple buoys connected to the seabed that create energy from the up-and-down motion of waves
• Two-body point absorbers — buoys attached to a “heave” plate on the seabed that resists the motion of the buoy, which in turn creates energy

Screenshot from the Small WEC Analysis tool displaying different WEC device types. Source: NREL

One of the primary use cases for the Small WEC Analysis tool is to provide an easy way to compare power output for a variety of WECs and model sizes. System designers can first identify the average wave height and length at a specific site using a resource such as NREL’s Marine Energy Atlas or the U.S. National Oceanic and Atmospheric Administration's National Data Buoy Center. The Small WEC Analysis tool is then called upon to determine how much energy a proposed WEC unit can produce in that sea state. The WEC design can then be modified to improve performance at the desired site, or compared with other WEC types.

This publicly available and easily accessible performance library is designed to give access to a more diverse field of technology developers without requiring hydrodynamic experience.