Well thanks for the well-reasoned and neatly laid out rebuffal, it's what I come to HN for. Perhaps "free from harmful emissions" would be better, I'm not in that field of expertise so I can't say, but if you take issue with plant based fuel over fossil fuels then I would like to hear that rational: preferably in a one word answer sans context. /bitchy
The better response would be (theoretically) "carbon neutral": as long as that diesel is run strictly on biomass-based fuels, the carbon cycle would be completed (it would would be "net zero" in pollution).
That doesn't mean it would be "pollution free", of course; no vehicle can be. For a diesel, you have various gases and particulates, but with proper capture and scrubbing, much of these can be disposed of in more environmentally friendly ways. Plus, most if not all of this tech is already developed and used on current diesel vehicles.
