Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 24

Thread: Harbor freight solar cell packages

  1. #11
    Join Date
    Dec 2008
    Location
    Texas
    Posts
    3,610

    Default

    Quote Originally Posted by 91CavGT View Post
    Not to mention the extra costs of the cable for a 12 volt system vs. the required cable for a 24v or 48v system. For example, I purchased a 16' length of 1/0 cable. It is some seriously large cable, but it was also $13 a foot! I use it for my 12v to 120v power inverter but am looking at upgrading to a 24v inverter down the road. Here is what 1/0 cable looks like, yes, it is the size of my thumb;

    No doubt.

    1/0 AWG is 53.5mm˛ and to run 3.2KW at 12 Volt you would need 500mm˛ wire (that's almost 10X thicker than 1/0 AWG) there's not even an AWG scale for wire that large, you have to switch over to the mm˛ wire size and I have no idea where you can buy cable as thick as your arm and I'd hate to see what it costs
    Last edited by Tdale; 10-05-2016 at 03:34 PM.
    NUTS!!!!

  2. #12
    Join Date
    Mar 2009
    Location
    Arkansas
    Posts
    553

    Default

    Yep, I'll be running a 48 volt battery bank, with 24 volt panels. There is a company in Texas that makes 48 volt panels, but they aren't always available...like now. Only when they do a large run for businesses.

    I was going to do all 12 volt until I realized OMG, what am I doing! The losses, and the cost, would be crazy.

  3. #13
    Join Date
    Jun 2008
    Location
    TN mainly, on the road alot.
    Posts
    5,558

    Default

    Tdale, the aluminum service cable they use for moving the grid is rated at more than 260amps isn't it?

  4. #14
    Join Date
    Dec 2008
    Location
    Texas
    Posts
    3,610

    Default

    Quote Originally Posted by Alredneck View Post
    Tdale, the aluminum service cable they use for moving the grid is rated at more than 260amps isn't it?
    Depends on the voltage.... Also I don't know where to buy it, how much it costs, or how many amps it can handle at 12V without knowing the specifics of the wire you're asking about.

    One thing to remember is that overhead power lines are normally running 3 phase AC and are usually 100 kV to 800 kV

    If you know the mm˛ if the wire you are speaking of I can run it through my calc and let you know how many amps it can take at 12VDC
    Last edited by Tdale; 10-07-2016 at 12:24 PM.
    NUTS!!!!

  5. #15
    Join Date
    Feb 2009
    Location
    Wisconsin
    Posts
    3,959

    Default

    I'm finding kits on ebay that look better and seem cheaper per panel on ebay.

    Ideally i want enough juice to run the fridge and the computer and a radio and the blowers for the furnace in the winter.

    IF i have to run the shop i think i need a gas gene or something. I have a lot of hand tools though.

    Thanks for the info, keep it coming. I know almost nothing about eletricity.

  6. #16
    Join Date
    Jun 2013
    Location
    AZ
    Posts
    1,121

    Default

    and the blowers for the furnace in the winter.
    Takes a lot of juice!

  7. #17
    Join Date
    Mar 2007
    Posts
    2,808

    Default

    Quote Originally Posted by X-cop View Post
    I'm finding kits on ebay that look better and seem cheaper per panel on ebay.

    Ideally i want enough juice to run the fridge and the computer and a radio and the blowers for the furnace in the winter.

    IF i have to run the shop i think i need a gas gene or something. I have a lot of hand tools though.

    Thanks for the info, keep it coming. I know almost nothing about eletricity.
    Not sure about your appliances but I was able to run the washer, dryer(gas), fridge and furnace(gas) on a single Honda EU2000i generator. That unit produces 2000 continuous watts with up to 4000 surge. The caveat was the dryer had to be started first, then everything else could be plugged in.

    I have a 2kw inverter and was able to power my fridge only for 2 days off my 560 watt solar array with 4 deep-cycle Trojan batteries before the deficit became unsustainable. That's four 140w 12v panels. You can find online calculators if you can determine how much load in kw-hours you need to run. Get a Kill-O-Watt meter and plug your devices into it for a few days, that should give you an accurate picture. In my opinion you'd be looking at at least twice that to power the fridge-only on an ongoing basis, but to get a real answer you will have to measure your load, and run the numbers.

    If you are talking about running those loads reliably on an indefinite basis (true off-grid) you're going to need a lot of panels and a lot of batteries to cover overnight and overcast situations which will be frequent. You can suplement by having a battery charger (such as IOTA) to replenish batteries if they start to get low on you. Best way to do this IMHO is to get up before sunrise, run the generator for a few hours to bulk-charge the batteries, and let the sun top them off. This is because the first 75-80% of battery charging goes quick, the last 20-25% just requires the voltage over time (several hours) to get back up to fully charged status.

    A laptop or tablet computer will use a lot less electricity than a desktop. A Mr. Buddy portable propane heater will warm up a small room nicely and uses zero electricity. These days McMansions have these huge great rooms that are expensive to heat and cool. We live in a 1300 sqft older home with 8' ceilings and is about 10x20 footprint. Put a curtain (or tack a bedsheet) across the doorway, and we can warm it up pretty nice in there, at least to where it's not uncomfortable in a sweater or lap-blanket. If your object is to keep plumbing from freezing set the thermostat on some low temp like 50 degrees and it will run your fan a lot less - then heat up your "warm room" with Mr. Buddy to 60-65 degrees. On a recent camping trip we used electric blankets that were run off my solar/battery combo and were cozy in our beds even though it got down to 40 degrees overnight. Those blankets don't have to be set very high if covered with a quilt/comforter, we had them set on level 2 and were plenty warm.

    We get in the habit of thinking "just like normal" and want it to be just like the grid - the reality is, we can get by on a lot less by thinking smaller. Does the whole house need to be 72 degrees around the clock? Or can we get by with sweaters and a space heater by day, and an electric blanket by night? Heat just the person or area needed? How about a mini-fridge or chest freezer (with thermostat modified to chill rather than freeze) to keep milk, meat and leftovers cool, rather than a whole fridge full of stuff that not all needs to be kept cold? How about an ice maker and a cooler? We start changing our thinking about things and suddenly new possibilities open up and things get easier.
    Last edited by bruss01; 10-14-2016 at 02:13 PM.
    In a crazy world, it's the crazy man who can get by - and it's about to get cray-cray up in here.

  8. #18
    Join Date
    Dec 2008
    Location
    Texas
    Posts
    3,610

    Default

    Quote Originally Posted by X-cop View Post
    I'm finding kits on ebay that look better and seem cheaper per panel on ebay.

    Ideally i want enough juice to run the fridge and the computer and a radio and the blowers for the furnace in the winter.

    IF i have to run the shop i think i need a gas gene or something. I have a lot of hand tools though.

    Thanks for the info, keep it coming. I know almost nothing about eletricity.
    Computers (laptops), radio, and Fridge.....no problem you can do this with relative ease.


    Blower, that really depends on the wattage and hours run per day. Do you know the specs of the blower you want to run? It might be helpful to look for a more efficient DC blower if you have a power hungry blower.



    Also Bruss01 has a very good point, you can get propane/natural gas fueled blue flame heaters that are safe to run indoors. They use no power and are very fuel efficient, might be a better option than spending a ton of money on batteries to store energy for the blower. Batteries will be the most expensive part of the system when factored over time

    http://www.homedepot.com/p/Reddy-Hea...TBDC/100672695
    Last edited by Tdale; 10-14-2016 at 02:16 PM.
    NUTS!!!!

  9. #19
    Join Date
    Sep 2009
    Location
    KC, Misery-- It's Missouri- you have to 'Show Me'...
    Posts
    8,948

    Default

    Heating is a bit of an issue for me... I just got a Mr Heater Big Buddy which runs off 20# propane tanks for an emergency back up... I have enough fuel to make it through a winter if needed... Not optimal but doable...
    leave the gun... take the cannoli...

    In times of strength prepare for times of weakness...

  10. #20
    Join Date
    Dec 2008
    Location
    A mud bog in East Texas
    Posts
    5,304

    Default

    Avoid the little kits

    Currently have 18 300 watt panels deployed.

    Panels operate at 37.5 volts dc.

    9 panels through midnite solar mttp charge controller x 2.

    5400 watts from panels at optimum. Charge controllers add as much as 30% in conversion to charging voltages.

    24 trojan t-105. Currently wired 12v. 2700 amp/hours max charge.


    Batteries feed 5kw inverter.

    Not grid tied.

    Runs rv, well pump..

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •