said by PSWired:
Gotcha. We have a bunch of above-ground outdoor heating oil tanks around here in MD, I guess it just doesn't get cold enough here for them to gel up. Outdoor diesel tanks for standby generators are popular too.
With proper additives and blending, diesel and fuel oil can be flowable to about -40... But it's all about the right mix.
Winter and Arctic diesel remain flowable at very low temperatures, but can be too thin for normal operation at higher temps... Summer fuels get too thick at lower temps.
I've got about a half-million litres of diesel and fuel oil stored at various sites; mostly in above-ground tanks - it's a bit of a dance to keep the blends right for the time of year.