Diesel vs Natural Gas Generator

SOURCE
https://www.eng-tips.com/viewthread.cfm?qid=461107
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QUESTION

I’m generator vendor sizing software. After I modeled all my loads, I got two different required generator ratings. Diesel type came out at a higher rating than the natural gas type. What gives? The electrical rating of the unit should not change regardless of the fuel type. Ideas?

REPLIES

waross
It has to do with the engines ability to accept and recover from block loading.
When a heavy load hits, the engine slows down slightly and then recovers.
An engine with more inertia may perform a little better.
A naturally aspirated engine may perform better than a turbo aspirated engine.
A PMG excited set may perform better than a self excited set.
The software is sizing according to the specified voltage drop when a motor starts.