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Old 10-16-2012
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Re: Optimal propulsion system

Stumble, I'd like to spend more time running the numbers because this scenario, replacing balast with batteries, is as good as it's going to get for electric boats. But a couple things jump out quickly.

Are you factoring in conversion losses? Diesel engines have an efficiency of about 45% and Electric motors are >70% (70-99.99 apparently) based on some quick googling. So that close to doubles your 4 gallons to 8.

Second, 2200lbs? My Contessa has more ballast than that. However I'm not saying 100% of balast should be replaced but many boats that size have far more.

And really, if we're talking 8 gallons of gas that's a lot. I've gone 2 seasons on less, at the least that's a significant passage even for a large boat.
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