How efficient are inverters? I have a single battery, single solar panel system in my trailer and it keeps up with my fridge, lights and 12v fan I use inside my RTT just fine. I don't use 110 much at all now but in the humid south having a fan running during the day is really nice. I have one that according to the specs pulls 85 watts. I run it with a 2000 w Honda but I would love to run it off my battery. Are more powerfull inverters more efficient at lower draws? Are the better inverters like Samlex more efficient, or just better quality?
Inverters
- Thread starter dcg141
- Start date
4x4junkie
Explorer
Inverters as a general rule are less efficient when used at low percentages of their rated power than when used closer to their ratings.
So a 2000 watt inverter will most likely use more energy to power your 85W fan than a 150 watt inverter would. 85W even just by itself is a rather sizable load for a single battery system...
I would suggest find a bigger 12V fan to use if the one you have isn't enough. This would keep an inverter out of the picture entirely. Look for 12V RV fans maybe. There are several sizes available in both clip-on and freestanding units that I suspect would satisfy your need (maybe something like this or this?) You could also fashion something out of a high-powered "computer-type" fan by making a mounting bracket, clip or stand for it (I have a 120mm x 38mm fan rated 1.2 amps that easily pushes as much air as a small desktop oscillating-type fan does but only draws ~15 watts. It is a little noisier though).
So a 2000 watt inverter will most likely use more energy to power your 85W fan than a 150 watt inverter would. 85W even just by itself is a rather sizable load for a single battery system...
I would suggest find a bigger 12V fan to use if the one you have isn't enough. This would keep an inverter out of the picture entirely. Look for 12V RV fans maybe. There are several sizes available in both clip-on and freestanding units that I suspect would satisfy your need (maybe something like this or this?) You could also fashion something out of a high-powered "computer-type" fan by making a mounting bracket, clip or stand for it (I have a 120mm x 38mm fan rated 1.2 amps that easily pushes as much air as a small desktop oscillating-type fan does but only draws ~15 watts. It is a little noisier though).
Scoutn79
Adventurer
if you don't need a lot of air movement look into the USB powered fans. I have a 6" one and it moves a surprising amount of air and the motor is very efficient. Large "computer" style fans can move a fair amount of air and are very efficient as well.
Both are considerable more efficient than the 120V units of similar size.
I don't think you can get them much bigger than 6" but I have not looked.
Darrell
Darrell
Both are considerable more efficient than the 120V units of similar size.
I don't think you can get them much bigger than 6" but I have not looked.
Darrell
Darrell
I actually have a bigger 12v fan. The 110 one is just easier to use because it pivots. That being said even well made low power inverters are inexpensive enough for me to give one a try. You have answered my question by stopping me from over paying for something I did not need. Thx for the feedback.
comptiger5000
Adventurer
Not even close. They're not necessarily very efficient at low load (input power might be significantly more than the output power), but there's no way a 1500 watt inverter is going to be drawing 150+ amps constantly unless it's at full load.
When I go riding just for the day, 90% of my use, I run the fan for maybe 2-4 hours tops and there is no other load on the battery. I got a 300 watt Cotek ordered and I will see how it goes. If nothing else it will be nice to have 110 available for things like drills and my small air compressor wo breaking out the generator.
bluejeep
just a guy
I stand corrected. Looks like I was given some bogus info. While an inverter that is turned on but not powering anything will not pull it's fully rated load as I incorrectly mentioned prior, there still will be some load on the vehicle battery, but much lower.
Sorry for the bad info.
plh
Explorer
I'm looking for a smallish inverter. I just purchased Jeff's creation http://www.expeditionportal.com/forum/threads/73403-Jeff-s-Cargo-Conversion and it came with a 2000 watt puresine Xantrex. Everything in the trailer is run off 12vdc. LED lighting, ARB fridge, fan, TV... I have no need for it. I could see charging an occasional laptop. That's about it, so maybe 150 Watts and probably doesn't need to be a puresine. Have 250 watts of solar and 200 amp hours of agm. Are most of the smaller inverters similar efficiency? If so I'll grab one from HF.
comptiger5000
Adventurer
FWIW, the Xantrex Xpower 1500 I have in the Jeep is spec-ed to pull 0.3 amps when turned on with no load. Efficiency spec is 90%, but they don't say at what load, so it is likely worse at very low loads.
rayra
Expedition Leader
OP's looking to build a full stadium for a sandlot ballgame. There are plenty of 12VDC-native air-mover fans available already. Inexpensively. Most equipped with a cigarette lighter / power port connector. The RV and Trucker markets have long had them. Worrying about conversion efficiences to power a 115VAC fan is just silly. Having 115VAC is a worthwhile thing for other uses, but just for a fan?
http://www.walmart.com/ip/Schumacher-12V-Oscillating-Fan-121/21642147 <--$15 and it oscillates
http://m.campingworld.com/category/fans/74
http://www.amazon.com/s?ie=UTF8&page=1&rh=n:15684181,k:car fan 12v
http://www.walmart.com/ip/Schumacher-12V-Oscillating-Fan-121/21642147 <--$15 and it oscillates
http://m.campingworld.com/category/fans/74
http://www.amazon.com/s?ie=UTF8&page=1&rh=n:15684181,k:car fan 12v
Hmmm, actually I have alot of uses for 110 and a low power inverter did not dig that far into my 401k. I have 12 volt fans, I have alot of fans because I live in Mississippi and I race off road motorcycles. You know, the deep south where in August its triple digits and 90% humidity. After a 2 hour endurance race with full gear and you have lost 10 lbs of body fluid and your gear is soaked so bad there is sweat in the bottom of your boots, the 12v fans don't cut it. Even if the oscillates. I have a big fan that I will sit in front of motionless for a good 1/2 hour before I start to get back to normal. It does not have to run 24/7 when I camp but its essential after a race to help cool me down. Not having to go fire up my generator to get it going is nice also.
See that smile..that's because my big fan is working
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