Random idea. Change emissions requirements based on GPS coordinates. That's sort of what they do in shipping. Ships burn cleaner fuel in port. If a semi is driv

Random idea. Change emissions requirements based on GPS coordinates. That's sort of what they do in shipping. Ships burn cleaner fuel in port. If a semi is driving around Los Angeles low emissions are important. In middle of Kansas not as much. That said phasing out diesels is better idea over the medium run.