Geez Darb, You like to open cans of worms when bored.

You are right. The real benchmark of what it takes to compare fridges from the ones above is W Hour which is a unit of energy. Like you get billed for a kW hour on your electricity bill. That is valid, not only for 24v, but you could even compare that to a gas fridge or a pedal power fridge.

Amp hour is a short cut people use on the assumption that the system is all 12v. What they don't say or generally know is they are referring to the charge consumed over a period when they say AH.

Amp Hours are really misunderstood and have nothing to do with elapsed time. You can have 1 AH over 1 hour, over 24 hours or even over a few seconds. A starter for a big diesel will also use about 1 AH on a cold day.

Amp Hours is a unit of Charge. Eg you have a 100 AH battery. That means it can deliver 100 Amps for 1 hour, or 20 Amps for 5 hours, or 1 amp for 100 hours. ( ignoring battery efficiency issues). there are 3600 Columbs in 1 amp hour.

When we talk about AH for fridge consumption, Amp Hours is meaningless unless you also add a time and like you did in your OP. And even then for like voltages.

Eg 24AH over 24 hours, or 1 AH over 1 hour. So people add a second short cut which is where the whole AH thing gets confusing.

Amp hours are not average amps over 1 hour. To get average Amps per hour, you have to get the total AH and divide it by the number of Hours. In other words average amps.

To answer your original question, IMHO people should stick to the convention, even though it is a short cut and say xx AH at 24V to be clear because everyone thinks they understand that.

Confusing huh?