How efficient are mariculture vessels?

September 11, 2023

Equipped with a newly designed data logging system, a team of researchers went on sea trials this summer to study energy use in shellfish and seaweed farms.

Kristian Nudlash-Barger, an ACEP summer intern and a sophomore in electrical engineering at the University of Alaska Anchorage, and Chandler Kemp, assistant professor of sustainable energy at the University of Alaska Fairbanks Bristol Bay Campus, traveled to Kodiak, Larsen Bay, and Sitka for their study. Their research aims to lay a foundation of energy efficiency and minimal emissions, as the Alaska mariculture industry — farming of shellfish and seaweed in salt water for human consumption — grows.

To track energy usage, the team deployed an NMEA 2000 data logging system, designed by Nudlash-Barger. The system consisted of an NMEA 2000 starter kit (a plug-and-play communications standard used for connecting marine sensors and display units within ships and boats), an engine interface cable to collect data on fuel consumption (measured in gallons per hour) and engine speed (measured in revolutions per minute or RPM), a GPS to collect speed and location data, a display to read the measurements in real time, and a data logger to store all of the data. 

During their three-day stay in Kodiak, Kemp and Nudlash-Barger met with several mariculture industry leaders. Nick Mangini and Alf Pryor gave a tour of each of their kelp farms. They demonstrated how they string-seeded lines between a system of anchors and buoys to make an underwater kelp garden. Alaska Sea Grant advisor Melissa Good explained that kelp harvested near Kodiak is currently immediately blanched and frozen. She wants to find a more efficient way to process kelp, which will be a part of future energy efficiency work.

In Larsen Bay, a small community on Kodiak island, Kemp and Nudlash-Barger met with Erik O’Brien, who runs an oyster farm. O’Brien wants to expand his farm by using a FLUPSY, or a Float Upweller System. FLUPSYs are used to grow shellfish in a protected environment by providing a steady upwelling of nutrition-rich water during their vulnerable early life stages, hence promoting accelerated growth. Data from five different vessels were collected from O’Brien’s operation during their stay in Larsen Bay, along with a better understanding of how oyster farms work. Nudlash-Barger is now working on a design and an energy estimate for a renewable FLUPSY. 

Kemp and Nudlash-Barger then went to Sitka to work with Angela Bowers, assistant professor at the University of Alaska Southeast Sitka Campus. She brought them along on a kelp harvest, where the pair conducted sea trials on two vessels.

Currently, Kemp and Nudlash-Barger are analyzing data they collected while on a total of seven vessels during their 10-day trip to determine the best fit for making greener, more efficient mariculture operations. Nudlash-Barger is working on improving the NMEA 2000 data logging system to make it compatible with as many vessels as possible. He is also working on a way to process the data efficiently with Python — a general-purpose, object-oriented programming language, widely used in data science. Kemp plans on collecting data from more vessels with aims to introduce electric or hybrid vessels into the mariculture industry.

Funding for this trip was provided by the Alaska Blue Economy Center at UAF. This internship is funded by the Office of Naval Research through the ACEP Undergraduate Summer Internship program.

For more information on this project, contact Chandler Kemp at ckemp6@alaska.edu.