What is the actual difference between fresh and subzero temp in your fuel costs per mile

I think it should be cheaper to maintain 35 rather than minus 10 ,my 2 pennies ,if I helped want my cut

 

Winter or summer?
Along i90 or i10?
It's hard to give an exact answer....

Summer I actually use more for fresh (42) than frozen (-10) since the produce I haul is generally still warm from the field...
Winter I can use more if continuous for say lettuce than cycle for frozen... now if the produce is at temp it will use less during summer than trying to keep frozen at -10....

Clear...?
:/

 

Basicly.... the bigger the difference between the temp of the product loaded vs what the set temp is.... then add whatever outside temp is... will determine how much you use...

If outside = 0f
Set point -10
Product -5
Use hardly any

Change outside to +90, probably double fuel usage

Change product temp to warm... triple fuel usage

It really can swing wildly...

 

The colder the ambient temp, the less the reefer, set on cycle, will run for either fresh or frozen. However, there comes a point when the temperature gets close enough to 35° that the unit probably won't run at all on a cooler load set on cycle but it will still cycle on for a frozen load, thus burning more fuel for frozen.

You'd think the same formula would be true as the ambient temperature reaches -10° or so, except, most reefer haulers, myself included, run the unit on continuous in subzero temps to keep the fuel from gelling up and/or having battery problems.

So the answer is no, it's not linear.

 

To answer the real dollars and cents, I'll take a chill load, that can be run on cycle, any day over a frozen. Depending on the ambient temp, it might be a $60 a day difference.

 

Winter time of year can cross the country -10F cycle on about $50 fuel.

Coming back with produce on continuous 38F it'll burn about twice that

So many variables... Reefer brand&model ... Trailer specs ... Climate ... Load required temps ... Mode ... load temps as loaded ... Iced vs not iced.. Etc etc etc

 

It has a lot more to do with cycled vs continuous cooling. Once a temp is reached (regardless if frozen or cold fresh) and the exterior temps aren't too hot, it costs almost nothing in fuel to run in cycled mode. I can go 3 to 4 weeks in cycled mode on a tank of fuel, but only 5 to 6 days in continuous mode. But I have a new trailer and reefer too. Older ones aren't very efficient.