MEP002 CNG conversion

[steelypip]

You can 'spike' a diesel engine with other fuels to reduce the amount of diesel fuel consumed. As other posters have noted, it works far better on direct injection engines. Propane or methane (natural gas) injection as a secondary fuel in small doses does work well to 'clean up' the chambers or reduce fuel consumption by some degree. I was planning on trying it on my MEP-002A as a curiosity (using an unlit propane torch held in the intake as a fuel source) when the set was running into a rated load on a load bank just to see what would happen.

A little project before that is to fit an 'injection rack protractor' on the genset, so that I can read the amount of fuel demanded by the governor as a percentage just by looking at it. Basically, it'll just be a pointer attached to a governor linkage arm that sweeps across a scale. I know exactly how I want to do it on the Listeroid, but haven't decided how to do it on the MEP yet.

 

[CDR]

Propane isn't as desirable in a fogging style bifuel as it's auto ignition temperature is lower than that of natural gas. And gasoline is even lower.

now, a spark ignition engine can use all three since sparks are pretty high temperature ignition sources.

That's interesting I didn't know that so more or less you have to run diesels on CNG OR NG

 

[blhar15]

We do what is called dual fuel, also DNG (Dual Natural Gas). These are very popular on larger diesel gen sets and larger trucks. We have been doing them on Class 8 highway trucks with Detroit Series 60 engines. There is a venturi that is installed prior to the turbo air intake. Compressed Natural Gas is sucked in to the air intake via vacuum pressure from the engine. It mixes with the air with only about 1% to 3% natural gas, low enough that it is not combustible by itself. By doing this all you are doing is giving the air some BTU's so when it goes in to the manifold on the engine, it senses there are some additional BTU's therefore reducing the amount of diesel fuel required for a given throttle input. We have seen displacements of diesel fuel as much as 60% depending on the application, therefore reducing the amount of diesel needed. Since natural gas is significantly lower in cost then diesel there are typically fuel savings of about 25%. The most expensive part of this conversion is the CNG tanks themselves. We can also use LNG and there are companies doing propane. The only issue with propane is the price fluctuation, as example look what propane prices did last winter.

Hope that helps, if you have any other questions let me know.

Thanks

 

[NEIOWA]

Cummins Westport is the big gun in the OEM market. Several sizes of Cummins converted to spark ignition. The carbon fiber pressure tanks are the big $ problem. The requirement periodic pressure test of these tanks is an additional expense.

http://www.cumminswestport.com/