Interesting thanks. I was thinking a day out range of 5/6 hours parked up so will do some maths with whichever coolbox I choose.

Out of interest I googled what Land Rover themselves sell, a branded 12v fabric cooler bag for over £200 it turns out, something I imagine as being more show than go when it comes to keeping things cool or warm… 2009 pre-facelift 3.6 TDV8.

Peltier tyes can heat or cool (just like the Peltier units in the front seats) but only by a fixed amount above or below ambient, so if it can chill by 10 degrees C., then in the summer heat, say 30 - 34 degrees, the contents will still be at 20-24 degrees C. Personally I prefer a proper refrigerant filled unit, for a start, they use less power and can chill to a setpoint independent of the ambient, Engel is my preferred brand but there are other good units.

JMC wrote:

My 2008/9 Vogue had a constant live in the boot cigar-plug socket. My 2012 has nothing left live a minute after switching off the ignition. All the cigar-plug sockets stay live for a minute after engine off, but then go dead!