4/23/2024 update.
I can’t find ULSD anywhere at all of my reliable stations that always had it. Every station I went to was selling a biomass diesel blend, some were labeled at the pump and others were labeled as ULSD. I did find real ULSD at a low volume station near Santa Cruz however I suspect it’s older fuel.
You can identify renewable diesel by the lack of foam and it is crystal clear. RD also has a different smell than ULSD.
My fuel economy has dropped 2 MPGs and low end torque is lower with more downshifting. I hate this crappy green fuel it sucks and the phony hype about how great it is. If it burns cleaner, but you use 10% more fuel to do the same amount of work, how is that an improvement? It’s a carb.gov greenwashing scam.