Researchers Investigate Laser Treatment to Reduce Corrosion and Biofouling on Marine Energy Devices

A team of Pacific Northwest National Laboratory (PNNL) researchers is investigating using a laser to modify the surface of marine energy devices to reduce corrosion and biofouling (the accumulation of plants, algae, and other microorganisms on device surfaces). Both corrosion and biofouling can disrupt marine energy devices by increasing the amount of maintenance needed, impacting the level of performance and potentially reducing equipment life spans. 

To combat corrosion, some developers build devices out of a higher-quality duplex or super duplex stainless steel. However, this material is more expensive and can increase the total cost of the device. Other developers use less expensive materials but coat them with an anticorrosion paint. A drawback of the paint is that it may need to be reapplied several times throughout the life of the device, which results in higher maintenance costs and downtime while devices are taken out of operation for painting. Further, antifouling paints/coatings are typically copper-based. When these paints and coatings dissolve into the surrounding water, marine wildlife may be harmed. 

The laser surface modification offers a potentially less expensive and more sustainable approach to protect devices from corrosion and biofouling. The modification was originally investigated to combat corrosion, but researchers also realized it could reduce biofouling in short-term trials. Following initial tests of laser surface modification for aluminum alloys, researchers are now analyzing how it could prevent corrosion and biofouling on aluminum and steel. 

This project is a "Sapling" funded through the Water Power Technologies Office's Seedling and Sapling program, which is designed to support innovative concepts and new ideas at the U.S. Department of Energy’s national laboratories.