Cool, huh? The fact that electric vehicles lost out back then and are now making inroads is pretty telling, IMO.
If there's a place where biofuels might make sense in creating electricity, I would think fueling trash trucks from trash could be a good idea. Unfortunately, NYC trucks its trash down here to VA and dumps it.
Given the relatively small amount of emissions I suspect it may make more sense (and cost less) to just use bio-methane directly for existing CNG garbage trucks (rather than turning it into electricity and then using it), as is already being done in a few places, e.g.:
Toronto Rolls Out Biogas-Capable Garbage Trucks
BSR developing biogas plant to fuel garbage truck fleet [in Berlin]
Eventually, it might make sense to use it for vehicle electricity, but the sewage plant itself will be burning bio-methane for CHP.