Ann: OptiBlend - Indian Market Update, page-38

"Replacing diesel generators is extremely expensive and impractical."

I doubt the diesel generators have to be replaced , more likely they can be retrofitted with the Optiblend set up or a competitors set apparatus .
Caterpillar petrol dozers were getting retrofitted with similar mechanisms back in the 1930s in California LPG was a waste gas prior to them finding a use for it so price was the reason for running them on Butane (LPG) ., just needed to increase the engine compression (high rise pistons or shaved heads ) and modify the carburetor with a vaporiser and regulator (to reduce pressure) .
I am guessing with diesel engines you would not have to increase the compression ratio to run on LPG

farmers got a 1000 gallon tank from the LPG provider and called up when they needed a refill

(My ex wifes family had a farm near Carmel California back in the 1950s made good money sending tomatoes on refrigerated rail cars to New York then bought a house literally in the middle of the Carmel golf course with the profits )