Posted: Sun Dec 14, 2014 1:17 pm
I guess we are missing the efficiency factor in here. AC figures should not kw but kwh; and kwh is a unit of energy whereas hp is a unit of power. kwh is the input in here (how much energy the engine consumes over one hour), and hp is the output (how much power it produces) Of course you can use kw as power unit in here and I assure you that when you feed an electrical engine with 1800kwh, you most probably get less then %85 of it back, rest is gone as heat, some invisible light and corrosion on the metal parts. And electrical engines are quite efficient compared to our lovely combustion engines...
Split ACs are quite efficient as there is no sacrificed space, but car AC system are a bit loose that end: the heat transfer method and space issues makes them working less efficient. That is why same energy may not end up same cooling. Similarly to the car engines: similar fuel consumption is giving double even triple hp today. (my first car was a W123 Merc with 2.0 Diesel engine giving around 60hp with 8lt/100km, now my brother is driving a Audi TDI 2.0 pulling 174hp with 6lt/100km. I always liked W123 though)
I tried to do a dyno when AC is on back some time ago yet failed as AC was automatically shut when you push the throttle wide open with the car. I never heard any official figure in here and 2hp seems quite optimistic given the lap times I have got with and without AC, I reckon we are talking about a good 5+hp here. I remember reading 20hp is spent for all the serpentine belt family (alternator + steering + ac etc...) yet can not confirm if it is true or not. There is no way to conclude this discussion until someone tries this on dyno...
I personally don't see any of the cars we are driving off-road will suffer due to AC compressor though, most of them are 3+ litres with 6cyl, pretty power enough to climb any dunes with L gears as we don't push the engine to the wto rpm limits... With all my respect to [MENTION=2551]ginger[/MENTION] (sorry [MENTION=1]admin[/MENTION], it will be hard to respect your experience on sand until someone will see you in flesh on a tricycle, at least a kids scooter :serious business:) I would say if you fail/stuck it wont be because of AC on the sand, as I can promise it will definitely be the AC if you try to beat your track record on a long straight.
Just my two cents...
[MENTION=9783]Daggerfall[/MENTION]: Apart from these calculations, blowing sand is not normal at all. What is gonna happen if it rains heavily then; a tiny Dubai Watershow inside the car? As [MENTION=955]caprihorse[/MENTION] put it right, the filter is supposed to FILTER it already, better to check it. It is usually a basic DIY job, I would just check youtube and sort it myself, change if necessary...
Split ACs are quite efficient as there is no sacrificed space, but car AC system are a bit loose that end: the heat transfer method and space issues makes them working less efficient. That is why same energy may not end up same cooling. Similarly to the car engines: similar fuel consumption is giving double even triple hp today. (my first car was a W123 Merc with 2.0 Diesel engine giving around 60hp with 8lt/100km, now my brother is driving a Audi TDI 2.0 pulling 174hp with 6lt/100km. I always liked W123 though)
I tried to do a dyno when AC is on back some time ago yet failed as AC was automatically shut when you push the throttle wide open with the car. I never heard any official figure in here and 2hp seems quite optimistic given the lap times I have got with and without AC, I reckon we are talking about a good 5+hp here. I remember reading 20hp is spent for all the serpentine belt family (alternator + steering + ac etc...) yet can not confirm if it is true or not. There is no way to conclude this discussion until someone tries this on dyno...
I personally don't see any of the cars we are driving off-road will suffer due to AC compressor though, most of them are 3+ litres with 6cyl, pretty power enough to climb any dunes with L gears as we don't push the engine to the wto rpm limits... With all my respect to [MENTION=2551]ginger[/MENTION] (sorry [MENTION=1]admin[/MENTION], it will be hard to respect your experience on sand until someone will see you in flesh on a tricycle, at least a kids scooter :serious business:) I would say if you fail/stuck it wont be because of AC on the sand, as I can promise it will definitely be the AC if you try to beat your track record on a long straight.
Just my two cents...
[MENTION=9783]Daggerfall[/MENTION]: Apart from these calculations, blowing sand is not normal at all. What is gonna happen if it rains heavily then; a tiny Dubai Watershow inside the car? As [MENTION=955]caprihorse[/MENTION] put it right, the filter is supposed to FILTER it already, better to check it. It is usually a basic DIY job, I would just check youtube and sort it myself, change if necessary...