The reasons you say environmentalists don’t like biodiesel seem relevant although I can’t weigh the environmental impact of those chemicals.
I am talking about why governments and environmentists dislike fossil diesel, not biodiesel. Though they also apply to biodiesel it’s worth it not to contribute to climate change.
I am not sure how easy it would be to convert a non-diesel engine to a biodiesel engine
I don’t think it’s possible. You would replace the engine. Still easier than replacing an ICE with an electric drive train.
We have reached the point in this discussion where it’s being said cars are still required for some people. I am trying to say how they can be made more environmentally friendly besides electric cars which are horrific to produce.
Electric trains don’t use batteries like electric cars use. Don’t know where you are getting this idea from. They take power from the grid via electrified railway.
Lots of trains run on diesel though. For these I think Biodiesel is also a good idea rather than trying to replace every single one. This is more for railcars than locamotives though, since all locamotives are electric anyway. Diesel locomotives have electric motors and drive train powered by a diesel generator; these are called diesel electric trains.
I agree that cars are necessary in some countries and places. Why are you preaching to the converted?
That’s why I am suggesting things like Biodiesel because I know cars aren’t going away everywhere. I also know diesel trains aren’t going anywhere for at least a decade, hence why I also suggest biofuels here too.
If you want a new car that’s good for the environment, buy a second hand diesel then use it with biofuel. You can buy or make biodiesel yourself. Some engines can run straight vegetable oil too or can be converted to do so. This is handy because vegetable oil can be bought from any super market and many businesses throw away used oil that cane be reused for running a car.