Just to make you all aware that from September to March, all fuel companies change
the chemical composition of the stuff we put in our tanks for the cold season.
This is to enable easier starting for both petrol and diesel.
However, the most noticeable change is to diesel fuel, where they also add an
'anti-freeze' to stop the fuel freezing, because in really cold conditions it can and
does freeze !
For those using an mpg calculator, more additives in your fuel means you obviously
get less of the go-go juice....and therefore a lower mpg than you have obtained at
other times of the year.
Conversely, cold fuel takes up less volume than warm/hot fuel (both diesel and petrol
expand when warm/hot), so you should effectively get more denser fuel into your tank
when you fill up, and should therefore get more mpg. But, although we all wish
that this was the case, any such gain is usually minor for motor vehicles.
In addition, as the weather declines, one must not forget that there will be slower
crawling traffic, heaters will be on full blast, heated rear/front/mirrors turned on,
wipers used, and radios/stereos....all to keep us comfortable. However, all of these
impose a further drain on the mpg, using up more of the 'black gold' that we pay so
much more for in the UK than any other country in Europe.
