Class 156 v 170 CO2 emissions

[clagmonster]

Would anyone happen to know the comparative carbon dioxide emissions between a 156 and a 2 car 170 perhaps on a per mile basis?

Similarly, I recall a 170, I think 170530 was involved in an emissions reduction trial, although I forget all details. Can anyone remember anything on this please? Articles about this would be most appreciated.

 

[Trainbike46]

Would anyone happen to know the comparative carbon dioxide emissions between a 156 and a 2 car 170 perhaps on a per mile basis?

Similarly, I recall a 170, I think 170530 was involved in an emissions reduction trial, although I forget all details. Can anyone remember anything on this please? Articles about this would be most appreciated.

I guess diesel consumption per mile would be a good proxy, if anyone has that information and is able to share?

 

[Geeves]

There was a thread a couple of years ago where Rhydgaled on here did some workings.

Class 195: 9.46 miles per gallon per vehicle
Class 170: 13.23 miles per gallon per vehicle
Class 158: 7.04 miles per gallon per vehicle
Class 156: 6.18 miles per gallon per vehicle

Seems quite reasonable! I had heard 158s at least were a fair bit lower than above I guess there are loads and loads of external factors. Less than a mile per gallon on departure but that's to be expected

 

[Trainbike46]

Thank you for those!

I'm surprised the class 195s seem to have worse efficiency than the 170s!

Then again, external factors, such as how hilly the route is, would definitely have an impact

 

[yorkshireguy21]

I'm surprised the class 195s seem to have worse efficiency than the 170s!

Perhaps their higher acceleration may lead to the lower efficiency?

 

[Richard Scott]

There was a thread a couple of years ago where Rhydgaled on here did some workings.

Class 195: 9.46 miles per gallon per vehicle
Class 170: 13.23 miles per gallon per vehicle
Class 158: 7.04 miles per gallon per vehicle
Class 156: 6.18 miles per gallon per vehicle

Seems quite reasonable! I had heard 158s at least were a fair bit lower than above I guess there are loads and loads of external factors. Less than a mile per gallon on departure but that's to be expected

Are those official figures as I'm sceptical. I seriously doubt the 170 figure is anywhere near correct especially with their hydraulic transmission that doesn't go into direct drive until somewhere near 50mph. Also 158 with extra air conditioning load and higher power with an engine that is essentially the same as a 156 using less fuel? Something doesn't stack up here.

 

[The exile]

Are those official figures as I'm sceptical. I seriously doubt the 170 figure is anywhere near correct especially with their hydraulic transmission that doesn't go into direct drive until somewhere near 50mph. Also 158 with extra air conditioning load and higher power with an engine that is essentially the same as a 156 using less fuel? Something doesn't stack up here.

Possibly the fact that if these were “in service” figures, the 158s were more likely to be on services with fewer stops therefore less acceleration from a stand.

 

[Richard Scott]

Possibly the fact that if these were “in service” figures, the 158s were more likely to be on services with fewer stops therefore less acceleration from a stand.

Ok, so is that an average as some fleets will be on different services to others? Can't imagine TfW 170s getting anywhere near that or those used on services around Birmingham, for example, with lots of stops.
So in essence what's quoted is an unfair comparison as the conditions are different for each class?

 

[Bevan Price]

Are those official figures as I'm sceptical. I seriously doubt the 170 figure is anywhere near correct especially with their hydraulic transmission that doesn't go into direct drive until somewhere near 50mph. Also 158 with extra air conditioning load and higher power with an engine that is essentially the same as a 156 using less fuel? Something doesn't stack up here.

156s are limited to 75mph; 158s are allowed to do 90mph, which will use more fuel.