The way that I see it is there are 2 kinds of pleasure boats that will cruise long distance and make ocean-crossings. Trawlers, and those boats owned by the very wealthy.
Trawler (noun): A fishing boat used for trawling.
Sue, the owner of m/v Lifeline, a 49′ converted fishing trawler reported, “After cruising the boat for twelve months we are consistently getting 7 – 8 litres per hour at 7 knots (1100 RPM) and we are ecstatic!!”.
MissLED offers charters, stating that one of the top ten reasons that the Grand Banks 36 is the best choice for a boat charter vacation is “Low Fuel Costs Keep you Moving – A Grand Banks trawler sips, not guzzles, its fuel. At the boat’s ideal cruising speed, a 36′ Grand Banks consumes a paltry 3 gallons per hour. You can cruise for a week and the refueling cost will not break the bank.”
Even the larger trawlers get great fuel economy. The Freedman family of M/V Sea Spirit gave detailed fuel economy data on their Sea Spirit Yachts Passagemaker 60 model (about 63 feet long). Again, you can see here, by their data tests that the faster the boat travels, the less economical it becomes.
3) Our envelope of possible fuel economies ranges from a high of 4.1 nautical MPG at idle and 5.8 knots, to a low of 0.6 nautical MPG at full throttle and a shade under 11 knots. Frankly, this entire range is pretty darned good for a 63 foot boat.
4) We seem to troll for fish at around 7 knots, which would get us 2 GPH or about $10/hour at $5/gallon fuel prices. This seems pretty darned good to us. This is 3.5 NMPG, or about $1.43 per NM.
5) When we’re not in a hurry, we often cruise at around 8 to 8.5 knots, at around 4 GPH, getting 2 NMPG, spending $20/hr or $2.50/NM for fuel. This is the speed we use when we’re moving the boat a short distance and just want to enjoy the ride.
6) When we’re trying to cover a larger distance in a shorter time, we often choose to cruise at 9.5 knots, burning around 9.5GPH. I can see from my chart that if I slowed down only 0.3 knots from 9.5 to 9.2 knots, I would lower my fuel usage from 9.5 to 7.5 GPH or 1.2 NMPG. While I don’t usually think too hard about fuel prices, if range were an issue, this would be worth doing. It seems that this is right around the point where fuel usage goes through the roof without much improvement in speed.
7) When we really need to get somewhere far away before dark, we open up the throttle a bit, and go at 10.5 knots. Still, this is only 1.3 knots faster than our normal “distance” speed, but uses 13.4 GPH rather than the 7.5 GPH we’d get at 9.2 knots. Clearly, we’re well into the area of diminishing returns here.
Motoryachts on the other hand are horrible on fuel. A 50-70′ motoryacht can easily burn 40-80 gallons per mile. M/V Dubai at 535′ is the World’s Largest Yacht. The fuel tank holds a whopping 277,410 Gallons of fuel, which would cost about $1,387,050 to fill at $5.00 per gallon.
If your very wealthy, which we are not, then you have the luxury of cruising a megayacht probably with crew, burning a gazillion gallons of fuel per second. The rest of us are best suited cruising in a trawler.
Even in a trawler, fuel isn’t cheap. At $4.00-$8.00 per gallon, it adds up and fast.
Then, there is the “fast trawler”. According to Beneteau, the Swift tops out at 26knots and cruises at 18knots. Keep in mind that the slower you go, the better fuel economy and range you will get. Here is the fuel/range chart for the Beneteau Swift 34 Trawler:
|Speed (kts)||Fuel Burn (US gal/hr)||Range (NM)|
If you are really frugal, and don’t need much room, a pocket-trawler, as described by Tom Tripp is a “small, salty vessel that’s probably a jack-of-all-trades and won’t break the bank”. The Nordic Tug 26 boasts a “range of about 150 NM on its 75 gallons of fuel, cruising at 8 knots”. That’s 2 miles per gallon. Awesome!
A trawler is the way to go for us. Now, we just have to find her!!!
What do you think about trawlers and fuel burn? I would love to hear your feedback. Leave a comment and your 2 cents!