Slow Speed Diesel Engines

95% of the worlds shipping fleet is powered by slow and medium speed diesel engines. Most of those being slow speed diesel engines. Shipping companies live and die according the the cost effectiveness of their ships. The Shipping industry uses lower quality for economic reasons. Slow speed diesel engines are capable of burning these lower quality fuels.

Electric companies are switching a lot of their power generation from medium speed diesels and steam turbines to slow speed diesels because of these efficiencies and longer life of the engine. Drop the speed of a diesel engine in half and its life expectancy more than quadruples. Slow speed diesel engines are capable of efficiencies of 50% and more.

With rising fuel costs and oil shortages people are looking for new answers. One fuel that has garnered a lot of attention is bio-diesel. Bio-diesel is produced by using a catalyst (lye) to break the chains of tri-glycerides freeing the ester chains from the glycerol and then recombining the chains with methanol or ethanol creating methanol-esters or ethanol-esters. Recombination with methanol seems to be the preferred method.

It is estimated that 3 billion gallons of waste vegetable oil is produced per year in the United States. This represents 5% of the entire Diesel used in the United States. This oil can be used as a fuel, either straight or processed into bio-diesel.

For the home do-it-yourselfer bio-diesel takes time and sometimes hard to get chemicals . It also makes a heck of a solvent, eating away paint and rubber, but bio-diesel may be used in high speed diesels without the fear of coking the engine.

Straight waste vegetable oil (wvo) is more suitable for slow speed diesel engines. For wvo to be used it only needs to be filtered and then heated to flow smoothly through the fuel system including the injectors. many people are using waste engine heat to accomplish this. The engine is set up with two fuel tanks and first started on common diesel fuel or bio-diesel. the engine is then switched to using waste vegetable oil once it is heated sufficiently.

Slow speed diesel engines are excellent for use with wvo. One engine that seems to be perfect for the home do-it-yourselfer is the Lister CS engine. While the RA Lister company stopped production in the 1980s clones of the engine are still being manufactured today in India and are called Listeroid engines.

Many of the Listeroid variants are running as fast as 1000 RPM. Original Lister Diesels were manufactured to run between 600 - 850 RPM. Keep in mind that engines and fly wheels are balanced for a specific speed and run best at those speeds. Also the slower the engine runs the longer one can expect it to last.