An interesting aside. The London bus that I get from Waterloo to my office is electrical. And yet on a cold January morning it smells worse of diesel fumes than

An interesting aside. The London bus that I get from Waterloo to my office is electrical. And yet on a cold January morning it smells worse of diesel fumes than the other buses as it has diesel heaters providing heat. I guess it's a sign of how efficient they are that there is not a suitable source of low grade waste heat from either the motors or the batteries.