Quote:
Originally Posted by sailingharry
So, the interweb tells me it's 10,500 nm from China to Brazil. The trip is predicted to take 6 weeks. This works out to 10kts.
Do freighters normally cruise this slow? How much diesel could a normal freighter save by slowing to 10kts, and how does this compare to the promised 30% savings?
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Slow speed is a very effective means of reducing
fuel consumption and CO2 emissions and is part of the means that the
marine transport industry is realizing their mandated emissions abatements.
Reference:
https://glomeep.imo.org/technology/s...n%20by%2027%25.
"SPEED MANAGEMENT
Speed management includes different aspects of adjusting and planning for optimal vessel speed and
engine load.
A.k.a. Slow steaming.
A vessel’s fuel consumption for
propulsion is a result of energy needed to push the vessel through the
water at the given vessel speed through
water. This relationship, between fuel consumption versus vessel speed, is typically an exponential one. As a
rule of thumb assuming that engine
power follows the cube of speed, a
displacement ship with 10% speed reduction reduces the
power need (resistance) and coherent fuel consumption by 27%. However, to assess the total fuel saving on a voyage basis one has to take into account the added time it takes to sail a given distance due to lower speed, yielding a total fuel saving of approx. 19%. For a selected open
hatch cargo vessel at 56 000 DWT presented in Figure 1, a 13% speed reduction saved almost 40% of the daily fuel consumption."