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Seeking The Truth
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Discussion Starter · #1 ·
I mean really small,like one panel for a fan.Thats what I can't be without is a fan!

Its hard to sleep at night without a fan.

The power went off last night and I was miserable.We don't keep the air going all day either,keep thermostate on 85 to 90 all day so candles don't start drooping or facing downward.

We do use fans though.
 

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I invented the internet. :rofl:
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1. Check the watt rating of the fan and multiply that number by the number of hours you'll need to run it. That's how many hours of storage capacity (battery size) you'll need. (A fan that uses 100 watts an hour running for ten hours equals 1,000 total watts used.)

2. Take the number of watts listed above and divide it by five. (Assuming you have five hours of direct sunlight on the panel each day.) This number will tell you what size of solar panel to get. (example 1,000 total watts used divided by five (hours of direct sunlight) equals 200 so you'll need a solar panel rated at 200 watts or some combination to reach the same output (two, one-hundred watt panels).

3. Get a charge controller with enough capacity for your panel(s). (In this case, 200 watts or 17 amps or more.)

4. Get an inverter large enough to power the fan (100 watt), or use a 12 volt fan and run it directly off the battery. (Actually you'll want an inverter with a 100 watt rating continuous duty which probably means the inverter should be 200 watts or larger.)

5. Wire it up.

6. Add 30 percent to all of the numbers you have above to make up for system losses. (For example, if you use 100 watts from a battery it will take 125 watts to recharge it to it's previous level.)

Obviously, the lower the watt rating of the fan the cheaper this entire system willl be. At these rates you'll have about $600.00 or more in panels, $200.00 in batteries, $100.00 in an inverter, and $100 in a charge controller plus whatever mounting hardware and wiring/fuses, etc. you need. You're looking at $1,000.00 minimum to run your fan. A lower watt fan would save a bunch but it will still be expensive.
 

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YourAdministrator, eh?
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First question I would have is what size of fan would you want? Something that moved a few CFM or something that moves a thousand CFM of air around? Your average fan that mounts to the ceiling of your house takes alot of power to start-up and once it is moving, uses very little power to keep going.

If you tie-in a UPS (Uninteruptable Power Supply normally sold in computer departments of various stores) to the fan, you could have anywhere from 1/2hr of fan-usage upto 10hr of continous fan-usage depending on model. American Power Corporation (APC) makes the most common UPS systems for computers and it would work just fine for other low-draw products (under 1000-watt like a full-featured computer).

Here in Canada, we will put the UPS onto our furnace-fan to keep it alive in the winter-time .. my UPS will keep my furnace going (off-n-on) for about 2 days as long as the outside temperature isn't bouncing off the -30°C both day and night.

Another option for you would be to install a UPS that charges off of both AC-power and solar-power having a limit of your reserve power (batteries). DC-AC Power.com has a 5,000 watt UPS for about $470, then you add the batteries (more batteries means longer run-time) and solar panels and misc. wiring to make the system work. You can tie in the 5,000 watt inverter to run your fridge and freezer ( small fan ) and run the majority of your house .. some low power-draw lights, maybe a laptop, your internet-connection, etc, but, you wouldn't want to cook off of it (stove or microwave).

Depending on the quantity of solar-panels and batteries, you could be looking at between $1000 to $5000 to setup your house with emergency power. Purchasing a quality generator (gas, diesel, propane, natural-gas) to do the same thing would set you back around $1000 initial cost and then there are costs for fuel and maintenance.
 

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Seeking The Truth
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Discussion Starter · #4 ·
Thanks to both of you for the info.But I was thinking $500 at the most.I know a few yeas ago we had storms and hubby set up car radiator fan and car battery for us.But if we don't have gas available [I refuse to store gas]then I need something to charge the battery.

I'll find out about the fan.

Any suggestions on solar for under $500?
 

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There are many options for solar-panels under $500, but, what most people don't realize is that while the panels themselves are "cheap" to buy, wiring, charge-controllers and batteries are all hidden-costs that are required to make the panels do what they have to do where there is no sun available.

A quick search on eBay for solar panels of 80watt rating show up at $230 to $600. Then you need the wiring (10-guage would be very light-duty, 4-guage would be about right) which could run you between $50 and $500 depending on the length of the wire required, then, depending on the solar-system you are building, you will also want a charge controller (from $50 to $250) and then finally, you will want two batteries that are rated for deep-cycle use (RV-style). If you want to run an AC-powered fan, then an inverter would have to be tossed into the mix. If you want to run a DC-powered fan, then no inverter would be required.



There isn't a "solar-system-in-a-box" that I know of, it is always custom-built to the purchasers requirements.
 

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Seeking The Truth
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Discussion Starter · #6 ·
There are many options for solar-panels under $500, but, what most people don't realize is that while the panels themselves are "cheap" to buy, wiring, charge-controllers and batteries are all hidden-costs that are required to make the panels do what they have to do where there is no sun available.

A quick search on eBay for solar panels of 80watt rating show up at $230 to $600. Then you need the wiring (10-guage would be very light-duty, 4-guage would be about right) which could run you between $50 and $500 depending on the length of the wire required, then, depending on the solar-system you are building, you will also want a charge controller (from $50 to $250) and then finally, you will want two batteries that are rated for deep-cycle use (RV-style). If you want to run an AC-powered fan, then an inverter would have to be tossed into the mix. If you want to run a DC-powered fan, then no inverter would be required.

There isn't a "solar-system-in-a-box" that I know of, it is always custom-built to the purchasers requirements.
Thanks,ths is helpful.Maybe I could get by with a small 40 watt.

I had a catalog that had what I was basically looking for.But can't find it now.
 

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I invented the internet. :rofl:
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Let us know what the watt rating is on the fan and how many hours you'll need to run it and we can go from there. If it's a 12 volt fan you won't need a charge controller. Harbor Frieght Tools has a 45 watt solar panel kit that would work with a small fan. Includes everything except batteries. It's mostly going to boil down to how many watts the fan draws.

Search results for: 'SOLAR PANEL KIT'
 

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Here is a link to a site that sells DC-powered fans.

DC Fans, DC Fan Blowers, DC Cooling Fans - QwikFlow

On the page there are links to some of their products and in the spec-sheets. Their model 1751 uses 12-volt and pulls upto 1.7amp - based on OHM's law, that means that fan pulls just under 21 watt of power to give you 336 CFM. That 45-watt panel kit that MMM linked in would power that one fan directly until the sun disappeared.

Just so that you know - that fan is designed for a computer-case. It wouldn't keep you very cool. The next choice would be an electric fan designed to keep a radiator in a car working properly. The most common electric fan used on Jeeps comes from a Ford Taurus - great CFM and easily mountable. I was not able to find the power-draw on it, but did find that most people recommend a 70 amp relay to handle the power draw on it.

Using OHM's law again, if the fan actually pulls 70 amp, it would be 840 watts worth of power! Lets say that the relay is over-kill and the fan only draws 50 amp of power - it is still 600 watt! Now you are getting into very expensive solar-panels (1000 watt combined power generating capability) to have enough power to keep the batteries fresh and to keep cool with a high CFM fan like from a vehicle.

Better choice - hire a cabana-boy to wave a palm-leaf for ya :eek:
 

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I have the HF panels x 2 + added 2 of the 15 watt panels. I have four 12 v deep cycle marine batteries. Not the cranking ones, the trolling motor ones. Can get 7 amps on a really bright day, 5.5 average. I have 2-410 watt inverters. Use a 30 amp controller.

I have two 9 in hi velocity fans. They are .8 amps @120vac. When out at the retreat for a 3-4 day weekend, I'm able to run the fans at night, some LED lighting and a small 14 in LED tv. I keep a homemade 12 v genset from a 5 hp briggs and a 120amp Motorola altenator. It is the back up if the sun does not shine. It will recharge the batteries in about 30-45 minutes.

Been using that combo for about 3 years with no major issues. I do want to add some more batteries, perfer the 6v golf cart type and another set of panels.

Didn't do the math as I should have, but wanted to experiment anyway. I got the panels for a song. Batteries 'nother story.... close to $350 for them. I have about $550 in mine for now. Iwould say if you are gonna spend the $$ get the golf cart batt. Sam's sells them now for $78 That's 10 bucks cheaper than I paid for my marine batt's. HF panels have been on sale lately.

Oh look at Northern Hydr/Tools too. They have a fair amount of solar/wind power stuff.

Good luck.

Jimmy
 

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I put SAs on IGNORE!
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It was 102 here today! You can not cool off outside in Texas. LOL
LOL....

95 here.

sometimes we just need a fan to breath outside, huh?

I keep fans on my front porch and back deck, I can completely understand why someone would want a fan ...but I think when TSHTF, we will be spending a lot of time outside, even sleeping outside like my dad did when he was a kid.
 

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99 yesterday...86% RH.....no place to get cool....

Jimmy
 

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I don't know much about the heat you guys are talkin' about, but, when it gets too hot for me, I head deep into the basement and lay on the floor to cool down - concrete floor stays cool all summer long and even with a thin layer of carpet, it is very comfortable to relax with a good book and a jug of fresh iced tea.
 

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Seeking The Truth
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Discussion Starter · #16 ·
Too bad we did'nt spend the mony on solar panels instead of generator that won't do any good if the gas is too high or runs out.

Hind sites 20x20.

All week for past 2 wks now the front porch has been over 100.And this is with fans and shades down.

We went through a couple weeks of no power when hurricanes hit'five in a row'here.This is when the car radiator fan hooked up to battery came in handy.

Thanks for suggestions and humor.
 

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Jack of all trades?
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The most common electric fan used on Jeeps comes from a Ford Taurus - great CFM and easily mountable.
Oh my - - no, don't suggest a Taurus or Mark VIII fan!!! Great fans for radiators, but they are loud and UNGODLY powerful - - you can't hold onto the shroud of one with hands when it powers up, unless you want to go for a WILD ride!!

We went through a couple weeks of no power when hurricanes hit'five in a row'here.This is when the car radiator fan hooked up to battery came in handy
Not a bad idea.... use small radiator fans, like those from a Honda Goldwing (or similar) motorcycle - - or a small import car. I have one that is from an old Honda Civic radiator (I think... it has been a while). It was mounted alongside another one - it is really small (the smaller of the two that were side by side) and pretty quiet. I have another small one that I got at a rummage sale that has a "Chrysler" emblem on it, and it is pretty darn small and pretty quiet, also.

You can use a simple automotive ammeter (0-30-0)to determine how much current your fan draws.
 
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