Cars are cleaner than buses.

[fungus]

This may be seen by some as inevitable coming from the ABD, but in SE Dorset there are a couple of bus opperators who are opperating buses in excess of 20 years old. Many are used on the school run.

Press Release 674



Cars ARE cleaner than buses
2009 report finds that, per passenger km travelled, cars emit less toxic pollutants than buses
A Transport and Travel Research Ltd (TTR) report published in March 2009 1 2 suggests that, on an average per passenger kilometre travelled basis, bus travel appears to have been more polluting in terms of toxic emissions than car travel over the last 10 years.

Key findings:
Nitrous Oxide (NOx) emissions from cars and buses have fallen in parallel due to Euro standards, but NOx emissions from cars remain well below those from buses.
Cars, vans and taxis also produce less NOx than rail.
TTR's expectation that Particulate emission reductions from bus exhausts will improve faster than those from cars seems optimistic given that Particulate filters are now being fitted in diesel car exhaust systems and Euro V emissions regulations are imminent.

Cars are also catching up with buses in terms of emissions of the much demonised non-pollutant Carbon Dioxide (CO₂). Small diesel cars and petrol hybrids emit less CO₂ per passenger km than buses.

The report makes clear the "importance of modernising the bus fleet if the bus is to be promoted as a reduced pollution option compared to the car" and "increasing the passenger loading can only go so far if older buses are kept in the fleet." No mention is made of the respirable carcinogens 1,8-DNP and 3-NBA that are emitted when large diesel engines, such as those fitted in buses, are under load. 3

ABD Environment spokesman Paul Biggs said:
“This report confirms that travelling by car is 'greener' than travelling by bus. Bus companies will have to invest heavily in fleet modernisation and the retrofitting of emission abatement technology to even stand a chance of keeping up with increasingly cleaner cars. This is a 'wake up' call to politicians who persist with the transport and environmental mantras of 'the answer's a bus, now what's the question?' Given that buses and coaches carry only 6.3% of passengers compared to the 86.5% who travel by car, van or taxi 4, should 6% of passengers be given up to 50% of the road via bus lanes? Furthermore, bus companies that have failed to retrofit emission abatement technology to older vehicles should be held to account.”

Nigel ADI
IAM trainee observer

[jont]

I imagine the same is true of the trains, given the operators round here seem to insist on continuing to run vintage stock rather than buying something fit for purpose

[ROG]

50 people on 1 bus causing X amount of pollutants
50 cars, 1 person in each, causing X amount of pollutants

Which of the two causes the most pollutants

[jont]

50 people on 1 bus causing X amount of pollutants
50 cars, 1 person in each, causing X amount of pollutants

From the original post: "2009 report finds that, per passenger km travelled, cars emit less toxic pollutants than buses"
I imagine part of this is due to the numbers of buses running at off peak times of day with only a few passengers rather than the peak time overcrowded services.

[michael769]

I imagine part of this is due to the numbers of buses running at off peak times of day with only a few passengers rather than the peak time overcrowded services.

Indeed. There is no doubt that a fully laden bus (carrying say 50 passengers) will produce substantially less emissions that 10 fully laden cars (carrying 5).

However, like cars, buses are rarely fully laden and during off peak times it is not unusual to find buses carrying only 2 or 3 people, and on rural routes many are completely empty for some part of their route. In those cases the buses do create more pollution, especially as they are subject to less strict emissions limits and are kept on the road for much longer (15-25 years compared to a cars 7-10).

[Sru_1980]

Good job I far prefer driving to taking the bus then - helping the planet AND enjoying it, wonders will never cease!!

[zadocbrown]

Sadly, there is more money to be made out of spanking car drivers than bus companies.