Preventing Biofouling of Oceanographic Sensors Using UV Illumination Powered by a Compact Wave Energy Converter

Oceanographic instrumentation is deployed in remote locations far from power grids, and in environments prone to biological growth that covers scientific instrumentation and interferes with data collection. The objective of this project is to extend the deployment period by capturing energy extracted from the motion of the instrumentation platform, and to improve scientific data collection by powering an anti-biofouling device designed to keep the instrumentation clear of biological growth. These systems must be cost effective, yet still survive in the harsh ocean environment. The small business worked with a research institution on a Phase I feasibility investigation. The detailed analyses completed in Phase I will be applied to the building and testing of prototype hardware in Phase II. These prototypes will undergo lab testing to verify operation and make improvements. The prototypes will then be deployed at sea for operational testing. Lessons learned from the sea testing will be captured as design improvements. The analyses conducted during Phase I demonstrated that significant energy is present in an oscillating buoy platform, energy that a buoy-mounted Wave Energy Converter (WEC) can use to power a light- emitting diode (LED)-based illuminator emitting in the sub-300nm ultraviolet spectral region. This LED was demonstrated to effectively prevent bio-fouling growth on optical window materials used in oceanography. This combination has the potential to provide a complementary source of renewable energy to charge batteries on a buoy when direct sunlight and wind are unavailable, as well as to power the anti-biofouling system directly to prevent biological growth. During lab testing, power generation will be quantified on a first-article prototype to be tested on a buoy motion simulator. Buoy motion testing results will be applied to a second version design. In order to simulate the ocean environment, the WEC, battery, and LED housings will be pressure tested at the research institution. Ultimately, the full system will be installed on an oceanographic mooring for at-sea testing. While deployed, the systems will be monitored and WEC performance will be analyzed based on transmitted engineering data. Complete system operation will be verified. Any necessary updates to the WEC control algorithm will be made after the deployment. The anti-biofouling unit will be mounted on a test conductivity sensor, and operation will be verified after deployment. Upon recovery, at-sea performance of the WEC and anti-biofouling system will be analyzed, evaluated, and updated based on lessons learned. The WEC and anti-biofouling systems will reduce operating costs by extending oceanographic instrumentation deployment periods with power generation and improved data collection.