SEPTEMBER 2009 - Association of Marina Industries

Clean Marina &
Environmental News
Boats and Biodiesel Alternative Fuels for
Marine Diesel Engines
Source: YachtPals.com
When last year’s fuel crunch hit, suddenly it wasn’t just the
patchouli-soaked and Birkenstock-shod who were looking
at other ways to fuel a vehicle. As the gas and diesel costs
shot up at the pumps, and even more at the fuel docks, a
lot of mainstream mass-consumers began to think that this
alternative fuel thing might not be such a bad idea. Suddenly,
that bearded guy with the sandals started to attract
quite a lot of new disciples and converts. No, I’m not talking
about Jesus. I’m talking about the guy who converted
his diesel car, or tractor, or boat, to burn something other
than petroleum.
To begin at the beginning, the internal combustion compression-ignited
engine was designed by Rudolf Diesel in
the 1890’s. He was sort of an “alternative” guy himself, and
part of his motivation was to figure out a way that small business
craftsmen could compete with big industry and their
huge, inefficient steam engine powered production lines. He
set about making a number of different designs for power
sources - even a solar-powered one - but what came to be
known as the Diesel engine was his crowning achievement,
and has really not changed that much in the past century.
Rudolph Diesel was a genius, no question there.
Diesel designed his first engine to run on lots of different
fuels, and at the 1900 World’s Fair, he used peanut oil - not
diesel fuel, which didn’t yet exist. What we call diesel fuel
is made from crude oil, aka petroleum (“petrodiesel” is
the new term we’re supposed to adopt), and it was made
to work with diesel engines, not the other way around.
It’s produced by basically boiling petroleum, and catching
what gets boiled off - distilling. After oil companies have
taken the most valuable parts of the distillate, the gasoline
and kerosene, next comes what are called fuel oils, which
include diesel grades 1-4. What’s left is called residuals
- diesel grades 5 and 6, or “bunker fuel” (what big ships
burn). This explanation has been greatly simplified (you
may Google fractional column distillation and crackers,
lubricating oils, etc.), but you get the picture: Diesel fuel is
literally what’s at the bottom of the barrel.
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The point is, unlike gasoline engines, which are very picky
with what they can burn, diesel engines will burn almost
anything, and petrodiesel fuel is just used because it’s the
cheapest thing available... Or, at least it was. But when oil
prices shoot up, this petrodiesel fuel becomes ridiculously
expensive, and alternative fuels become a lot more attractive.
When petrodiesel fuel cost $2.50 a gallon in the US,
and biodiesel cost $3.50, there wasn’t a lot of interest outside
the granola crowd. But, when petrodiesel hit $4.50,
you could hear rednecks say: “Hey buddy, let me buy you a
vegan burrito and let’s talk about that crappy old VW diesel
of yours with all them funny stickers.”
What are Biofuels
Basically: Petro-fuels are made from things that died a long
time ago, while bio-fuels are made from things that died
recently. Most biofuels are derived from vegetables, but
can be made from animals, so you really can “put a tiger
in your tank,” or drive home from the plastic surgeon in a
car fueled by the fat you had liposucked out, but that’s not
really politically correct (and it probably won’t smell great
either). Vegetable oil is what’s most often used in the production
of biofuel, and in biodiesel it’s processed to remove
the thickening glycerin and some other stuff that may be
damaging to an engine.
Notice I say “may be damaging” Remember that in 1900,
ol’ Rudy Diesel was using peanut oil, not some government-approved
“fuel”. A lot of people are running diesels
on straight vegetable oil (SVO) right now, today, with no
problems. In fact, when the US fuel prices were so very
high recently, many people were going to warehouse stores
and buying bulk veggie oil for about a third less than diesel
fuel cost at the pumps, and just dumping it in their tanks.
Others are using straight waste vegetable oil (WVO - from
restaurants mostly) to get around. Some say that there are
some really good reasons not to do this in your $10-, $20-,
or $40-thousand-plus marine diesels, though others say
that’s an industry-promoted fallacy.
Case in point: Wärtsilä, a manufacturer of ship propulsion
systems and big generating plants, decided to test some
weird stuff in one of their “small” (around 2,000 hp) engines
last spring. They not only tried vegetable (jatropha)
oil, but fish and chicken oil as well. And the results were
Clean Marina & Environmental News Continued on Page 12