So buses are the green way to travel are they? Well it clearly depends on how you measure their environmental credentials. The latest figures from the DfT show that fleet average CO2 emissions for buses have risen by about 25% over the past decade (the figures are plotted below alongside similar data for rigid and articulated HGVs). The numbers tell you what is happening but not why. Perhaps buses are getting bigger and heavier because they can carry more people.
Of course what is more important here is the average load factor per bus and the subsequent CO2 emissions per passenger kilometre – rather than vehicle kilometre. Even so it would be interesting to hear what the ‘official’ reason is for the steady increase in bus emissions compared with the steady decline in those for cars.