Large Blower Fan VS. AC

[Postal268]

I'm terrible at finding answers on the internet so I hope this hasn't already been answered but

My AC is currently broken so I had the idea to put a large blower fan (for ventilating a house while painting or something) in the passenger floor to cool me off. It seems to draw A LOT of power. It's currently hooked up to a 160watt inverter. I can really only use it for an extended time on the lowest setting, haven't tried the medium but on the high setting it'll trip the inverter to turn off cause it can cause the voltage readings to dip below 12 if I'm playing music at a high enough volume to hear over the blower and my sub hits too hard. I for certain can't use my headlights and the blower at the same time.

My question is, will this possibly impact my fuel economy the same as if I were just running the AC?

[M_a_t_t]

First thought without too much thinking, yes. But maybe no.

When the voltage drops low it means the alternator can't supply enough power. This isn't the case when the a/c is running, but the a/c is not powered by the alternator. However if the fan and a/c consume roughly the same amount of power (mechanical via belt or electrical power) then the engine would/should be using the same amount of extra fuel to run. Since the a/c doesn't work it's impossible to test and be able to tell. Plus the a/c runs only part of the time so you would have to average the energy useage vs the constant draw from the fan.

TLDR:
Too many variables to say.

[redpoint5]

I've read that electrical consumption robs twice the power from the engine. 150 watts then consumes 300 watts of power from the engine (about half a horsepower).

Can you get the AC working again by recharging it?

[Postal268]

My air conditioner is going to be a hard fix, I had a collision with a very large wild dog on the highway at around 60mph, this crushed the entire front end in destroying my radiator and AC condenser in the process. When I fixed it I got a half sized radiator for replacement to make room for possible upgrade to a turbo later on but the radiator is slightly too tall so for now I had to tilt it forwards to make it fit which is taking up the room the AC condenser is supposed to be in. I have a possible solution but it requires replacing the entire front support with a smaller one I have on my spare car. Second issue is AC control panel is busted and they cost around $450 for a new one. Third issue is I don't know if any of the present components for the AC work or not since the AC lines were all missing when I purchased the car and I had the accident right after I purchased them.

TLDR: AC needs A LOT of work.

[cRiPpLe_rOoStEr]

In my country it's quite common to see commercial trucks resorting to a swamp cooler instead of a proper air conditioner. Even though such swamp coolers are also resorting to water as a coolant, which allows them to run a comparatively smaller fan, most likely a large fan would still require fewer power to run than the compressor of an air conditioner. BTW maybe you could be tempted to try making your own all-electric air-cycle air conditioner, more similar to the one fitted to aircraft than to the regular vapour-cycle ones...

[Drifter]

I've only recently hooked up my scangauge to my prius and the weather has been mild, but on an 85° afternoon its electric air conditioner draws over 1,000 watts when first cooling down the car and then maintains the cabin temperature drawing 350-550 watts. So I think it is a safe bet that a fan which runs off a 160watts inverter uses less power.

[MeteorGray]

I live in an area with high relative humidity along with high temperature. In order to be comfortable here, it is just as important to reduce the humidity as it is the temperature. So, a fan by itself is not adequate to maintain comfort, even though it is easier on fuel economy than an air conditioner.

[Postal268]

Originally Posted by cRiPpLe_rOoStEr

In my country it's quite common to see commercial trucks resorting to a swamp cooler instead of a proper air conditioner. Even though such swamp coolers are also resorting to water as a coolant, which allows them to run a comparatively smaller fan, most likely a large fan would still require fewer power to run than the compressor of an air conditioner. BTW maybe you could be tempted to try making your own all-electric air-cycle air conditioner, more similar to the one fitted to aircraft than to the regular vapour-cycle ones...

Yeah, I designed my own sort of swamp cooler last year where I had a small cooler filled with ice and a small fountain pump that would pump the ice water through some copper tube that I coiled in-front of a fan. Issue one is tipping over and leaking but could have solved by tying it down. Issue two was the fan was too small. Issue three was the cooler was too small so all the ice melted within an hour. Just all around it was too small and too much work for not enough results. Blower fan alone works better, doesn't cool the car down but it certainly cools me down lol

Airplane AC sounds interesting, never even considered that they may use different tech before. I'm going to have to do some research on those to see how they work. Thanks for the tip

[Postal268]

Originally Posted by Drifter

I've only recently hooked up my scangauge to my prius and the weather has been mild, but on an 85° afternoon its electric air conditioner draws over 1,000 watts when first cooling down the car and then maintains the cabin temperature drawing 350-550 watts. So I think it is a safe bet that a fan which runs off a 160watts inverter uses less power.

Awesome, so even with continuous running it should be less of an issue than AC. thanks for the info

[cRiPpLe_rOoStEr]

Originally Posted by Postal268

I designed my own sort of swamp cooler last year where I had a small cooler filled with ice and a small fountain pump that would pump the ice water through some copper tube that I coiled in-front of a fan. Issue one is tipping over and leaking but could have solved by tying it down. Issue two was the fan was too small. Issue three was the cooler was too small so all the ice melted within an hour. Just all around it was too small and too much work for not enough results.

Swamp-coolers available commercially in Brazil are different, usually fitted to the roof of a truck as a self-containing unit, while others have an external water reservoir. They might not be exactly the most beautiful setup, but it's still common here.
https://engineeringworkarounds.blogs...-in-truck.html

https://engineeringworkarounds.blogs...window-t2.html

https://engineeringworkarounds.blogs...udget-yet.html