The U.S. Maritime Administration has issued a report regarding the design and construction of new battery components, examining the risks and benefits of battery use in the power plant of a hybrid tugboat.
In August of 2012, an explosion and fire occurred in one of the lithium‐polymer batteries on the Foss hybrid tug CAMPBELL FOSS. Subsequent to that fire, Foss removed the remaining batteries from the CAMPBELL FOSS and all of the lead‐acid batteries on Foss’ other hybrid tug, CAROLYN DOROTHY. CAMPBELL FOSS was returned to service in diesel configuration without batteries, and CAROLYN DOROTHY was returned to service in a modified hybrid configuration that did not require the use of batteries.
At the time of the fire on the CAMPBELL FOSS, Foss was applying for MARAD Maritime Environmental and Technical Assistance (META) program funding to help pay for the hybrid conversion of a sister vessel, the ALTA JUNE, from conventional propulsion to a hybrid system similar to the one installed on the CAMPBELL FOSS. Foss was awarded META funding from MARAD for the conversion. After the fire, Foss decided not to pursue the hybrid retrofit until such time as the battery installation could be proven to be safe.
The role of batteries in the hybrid system is not well understood; however, the risk of fire from lithium batteries in various platforms from computers, airplanes to tugs has been well documented. Anecdotal evidence suggests that the use of batteries in a hybrid tug system poses an impediment to more widespread adoption. Therefore, Foss requested to use the funds from MARAD to put batteries back into the two existing hybrid tugs after completing a risk assessment and incorporating lessons learned from the CAMPBELL FOSS fire. The revised project plan also included emissions testing with University of California Riverside (UCR) to quantify the benefits of moving from a Tier 2 to a Tier 3 auxiliary generator in this same hybrid application.
There is no doubt that hybridization is an excellent way for vessels with variable duty cycles, such as harbor tugs, to reduce all emissions as well as fuel and maintenance costs. The hybrid technology used in the CAMPBELL FOSS was verified as a diesel reduction technology by EPA in 2012 but has yet to gain widespread acceptance in the United States. This project further quantifies the benefits from hybrid technology and serves to promote the adoption of this emissions reduction technology for the public benefit. MARAD agreed and awarded Foss $600,000 in funding to help offset the costs for this project.
Please click below to read US MARAD report
Source: US MARAD
