Considering that the purpose of that 6th gear would be to lower the fuel consumption, that means we have a bunch of buses running around burning more fuel and polluting more all in the name of more profits.
At least school buses spend a lot of time driving around at relatively low speeds so the lack of the extra gear probably has little real-world effect for most of the time, but still…
we have a bunch of buses running around burning more fuel and polluting more
An even worse factor is that EPA regulations governing diesel engine emissions specify allowed emissions in terms of horsepower-miles, which means that more powerful engines are allowed to emit more pollutants per mile. This has led to school buses becoming over-engined compared to what they used to be a few decades ago (in the '90s bus engines in the neighborhood of 200 hp were typical, now 350 hp is normal). This is good for lead-footed bus drivers and the people behind the buses (I guess), but not so good for the air. And of course EPA diesel regulations specify nothing about greenhouse gas emissions.
At least school buses have the intrinsic efficiencies of mass-transportation behind them. If parents were driving all these kids to school instead, the net emissions would be vastly worse. Of course most of these kids could walk or bicycle instead …
Considering that the purpose of that 6th gear would be to lower the fuel consumption, that means we have a bunch of buses running around burning more fuel and polluting more all in the name of more profits.
At least school buses spend a lot of time driving around at relatively low speeds so the lack of the extra gear probably has little real-world effect for most of the time, but still…
An even worse factor is that EPA regulations governing diesel engine emissions specify allowed emissions in terms of horsepower-miles, which means that more powerful engines are allowed to emit more pollutants per mile. This has led to school buses becoming over-engined compared to what they used to be a few decades ago (in the '90s bus engines in the neighborhood of 200 hp were typical, now 350 hp is normal). This is good for lead-footed bus drivers and the people behind the buses (I guess), but not so good for the air. And of course EPA diesel regulations specify nothing about greenhouse gas emissions.
At least school buses have the intrinsic efficiencies of mass-transportation behind them. If parents were driving all these kids to school instead, the net emissions would be vastly worse. Of course most of these kids could walk or bicycle instead …