London&#x27;s bus fleet is also pretty new.  All meet Euro 4, and over 20% at least Euro 5. [1]<p>The taxis are the problem -- London&#x27;s low emission zone (similar to those in Germany) only applies to large vehicles, taxis are not included.  There are thousands of taxis over 10 years old still running in London [2].<p>&gt; So most buses in Germany are Euro VI now.<p>Really? That would mean most buses in Germany are less than 3 years old, which seems unlikely.<p>[1] <a href="https:&#x2F;&#x2F;tfl.gov.uk&#x2F;info-for&#x2F;media&#x2F;press-releases&#x2F;2014&#x2F;july&#x2F;world-s-largest-bus-retrofit-programme-compjeted" rel="nofollow">https:&#x2F;&#x2F;tfl.gov.uk&#x2F;info-for&#x2F;media&#x2F;press-releases&#x2F;2014&#x2F;july&#x2F;w...</a><p>[2] <a href="https:&#x2F;&#x2F;www.whatdotheyknow.com&#x2F;request&#x2F;spread_of_ages_of_londons_black" rel="nofollow">https:&#x2F;&#x2F;www.whatdotheyknow.com&#x2F;request&#x2F;spread_of_ages_of_lon...</a>