45Watt solar panel kit?

Discussion in 'Energy & Electricity' started by solaceofwinter, Jan 8, 2009.

  1. solaceofwinter

    solaceofwinter Guest

    I found a solar panel kit that is 45 watts. What usage would this be ideal for? it has 3,6,9,12 volt outlet.
    Last edited: Jan 8, 2009
  2. northernontario

    northernontario Well-Known Member

    what could you use this for? Whatever you wanted to do.

    Solar panels charge a battery bank. Then you use that battery bank to power 12v items, or using an inverter, to power 120v items.

    The limiting factors are:
    -number of hours of sunlight
    -storage capacity of the battery bank
    -size of the inverter

    You can always add more panels as time goes on.

  3. endurance

    endurance Well-Known Member

    Are you talking about the Harbor Freight set? If so, they've got the benefit of having a 12v battery charger circuit on them too. I figure the deal is good enough to have if you're not planning on expanding, as they're wired specifically for their own charge controller.

    I bought one to charge a deep cycle battery. I have a 1200w inverter and with that set up I can power about one appliance a day (i.e. bread machine) or run the pump on my boiler. While it's not a lot of power, it's better than nothing and the price is right.
  4. endurance

    endurance Well-Known Member

    Harbor Freight also has some cheap inverters. While I wouldn't trust your sensitive electronic devices to them, they'd certainly be a good way to power some lights and perhaps a few appliances in a pinch. Obviously some type of storage device (ie. deep cycle battery) would give you the ability to use higher power devices (using 8 hours of sun energy in an hour) and anytime you wanted it, even when the sun is down.
  5. ogre control

    ogre control Guest

    Harbor Freight panels

    I have two sets, and am installing two more next weekend. One set will not be much use, two sets will giuve an ample amouny to recharge three deep cycle batteries, This will provide power to run a TV set for an evening an lights. I use it on a daily basis to power my fish pump and lights. I will be able to supply power for my lights in my living room and family room with the next set.
    go to: Off grid solar power control system
    this site is an excellent source to check out in regards to the H.F. panels.
    I highly recommend the panels, you will pay $1 less per watt versus name brand panels. Great way to go if you want less than 500 watts in panels.
  6. NaeKid

    NaeKid YourAdministrator, eh?

    After doing my own testing with several different solar-panels, I would say that would be an alright panel for basic charging of non-essential systems. For my trailer, an 80 watt is about as low as I would want to go, but, have the capability of running upto 240 watts of power production.

    Right now, my 80watt can keep my dual 6-volt batteries alive and kicking (so far, all summer without any issues) - if I was going to go full-time, I would probably run several circuits of 240 watt each to their own battery-banks.
  7. endurance

    endurance Well-Known Member

    I had an interesting conversation with a spry ol' chap that told me recently that it's not the sensitive electronic devices that need to be watched after with the cheaper inverters so much as electric motors. He pointed out that most devices like laptops and cell phones use chargers that detect incoming voltage and automatically switch from 240 or 120vac to 5-14.5vdc as required. At worst, the charger is in danger, but the risk to the laptop or cell phone is neglegible. The problem comes with electric motors since the power on cheap inverters is a square wave or modified sine wave rather than a true sinewave, so it causes heating issues. This is a particular risk to refrigerators and freezers, as well as furnace motors and boiler pumps.

    Just something I found interesting and somewhat concerning.
  8. purity

    purity New Member

    Hey smart people, so i know nothing about solar stuff, so i do want to run my 52" panasonic lcd tv or my 20 cf fridge, i went to harbor tools but the kind of answer i was getting from this guy made me nervous and i did not buy solar panels from them. If i bought 2 45 watts panels, is that enough? What else do I need to get the ball rolling and screw my public elec company, feel free to email me reply if you don't mind ([email protected]) thanks, tom
  9. machinist

    machinist Rest In Peace

    Our answer for possible inverter problems was to run everything we could directly on 12 volts DC. Inverters have an inherent power loss in the process of converting DC to AC; the better ones being more efficient. Since most electronics run on DC anyway, why bother to convert to AC, then have the laptop, or whatever, convert it right back to DC again? Two losses instead of one.

    Our Dell laptops are happy on direct 12VDC. Since they have proprietary (read that as impossible to find one) power plug, I bought some standard 12 volt male and female plug sets. I cut the wire between the computer black box power thingy and that special plug that fit the computer socket. Then I reconnected it with a M-F plug-socket set I soldered in. Now, I can unplug the AC gizmo that came with the computer and use a patch cord I made with another 12V standard plug and battery clips on the other end. No problem. Cost me 6 bucks for the plugs. (I don't have the source, since I had my computer store order them for me.)

    We found a nice small 12 volt TV at a truck stop store that draws about 60 watts. Not bad for a 17" set.

    There are a host of 12 volt lights available. We chose CFL bulbs that have a standard Edison base like 120 volt bulbs. http://www.led-cfl-lighthouse.com/

    That way we can use cheap standard light fixtures and simply put a cigarette lighter plug on the original cord--checking carefully for proper polarity,of course. http://www.altex.com/Philmore-Auto-Power-Plug-with-10-Amp-Fuse-TC777-P141416.aspx

    I got the sockets here: http://www.oreillyauto.com/site/c/d...d=cigarette+lighter+socket&pt=N0318&ppt=C0092

    We still have to run the fridge and freezer off a good inverter, but the winning part is, that inverter can be much smaller (and thus cheaper) than if you ran the whole house from it.
  10. MrDean

    MrDean Off Grid Pioneer

    Guys, be careful. There are several types of inverters. You need to find out if it is a true sine wave inverter or square wave inverter when converting from DC battery voltage to AC 120 voltage. DC= Direct current, AC= Alternating current. Any device with a transformer as in all wireless tool battery chargers, TV's, refrigerators etc require a true sine wave inverter. Overheating and a serious loss of efficency which results in a greatly shortened device life result with the wrong inverter.

    As you can imagine, a true sine wave inverter is more expensive, going on the cheap is a LOT more expensive in the long run.

    That Harbor Freight jun......er...ah....stuff won't run your LCD TV or 20 CF fridge and if so, only for a very short while.