Starting this month, Toyota's hybrid cars might be arriving on a hybrid ship augmented by solar power.
We first told you about the Auriga Leader, a 60,000 ton carrier that can ferry up to 6,200 cars, back in 2008. It was retrofitted with a giant bank of solar cells in hopes of reducing CO2 emissions and fuel use while carrying mostly Toyotas across the Pacific.
During tests, solar energy made up for one percent of the ship's total electricity usage -- a small percentage, but enough to save 13 tons of fuel. However, solar power also turned out to be just too unreliable as even as a secondary standalone power source on such a large vessel, causing major spikes and shortages of electricity depending on cloud cover.
"Even a slight change in the weather has a significant influence on the amount of power generated," said NYK line, the Japanese operator of the *Auriga Leader. *Engineers looked into expanding the number of photovoltaic cells on board, but found that just exacerbated the problem of passing clouds and storms. "Attempting to make the solar power system bigger to gain more output and to increase its dependency could result in problems with regard to stable operations due to fluctuations in the power supply," the company said.
Researchers turned to the same solution that land-based solar generating stations use to keep the power on when the sun isn't out: really big batteries.
The Auriga Leader is setting sail this month with hybrid power system that's been under development since 2009. On board are massive Gigacell branded nickel-hydrogen batteries, developed by Kawasaki Heavy Industries. The batteries charge and discharge based on the power demands of the ship and the electricity generated by the solar cells.
The latest test is partially funded by Japan's Ministry of Land, Infrastructure, Transport and Tourism. If it's successful, Kawasaki and NYK line hope to commercialize it to decrease the emissions and fuel use of cargo ships, which burn an average 120 gallons of fuel per mile.
In addition to the solar cells, the Auriga Leader's diesel generator is also being retrofit to run on low-sulfur diesel, and the ship getting a ballast water treatment system to prevent the introduction of invasive species to the ports it visits.
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Photos: NYK Line
