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Solar panel for shed roof

  • 28-03-2020 4:07pm
    #1
    Registered Users Posts: 735 ✭✭✭ wannabecraig


    All,

    Looking to get a solar panel for the roof of my shed. I just want it to power some lights in the garden at night, and maybe a pond pump in the future.
    I'm trying to figure out if I can get one and then add the lights or other devices on later? Like are the solar panels fitted with universal adapters
    that just connect to lights that only power on at night or are the all connected to a battery that stores the power etc?
    Obviously very new to this so any advise on this would be great.


Comments

  • Moderators, Category Moderators, Motoring & Transport Moderators, Regional East Moderators Posts: 58,822 CMod ✭✭✭✭ unkel


    You can't use a solar PV panel to power lights at night as PV produces zero electricity in the dark. You will need to store the electricity from the panels into a battery during the day, and that battery can then power the lights at night

    For a really cheap and simple setup, get a small 12V PV panel and a cheap solar charge controller (this charges up your battery) for EUR25 like this:

    Linky

    And use an old car battery that you might have lying around (one that is too dead to be used in a car is probably still fine for this)

    And a cheap 12V LED light strip with dawn / dusk sensor

    Linky


    Total project cost around EUR35. A lot cheaper than that again if you order from the likes of AliExpress and don't mind waiting a month or so for it to arrive

    Happy new hobby :)

    But beware, it's addictive!

    "Wind is Ireland's oil" - An Taoiseach, 25/05/2022



  • Registered Users Posts: 407 ✭✭ phester28


    just a word of caution about aliexpress. Most solar panels figures would be grossly exaggerated. PWM charge controllers are fine and cheap and will get the job done. Most likely listed as MPPT charge controllers.

    Get a feel for how big a panel is for poly or mono silicon and you could estimate whether the figures quoted are ballpark or just plain off the wall


  • Registered Users Posts: 2,946 ✭✭✭ randombar


    Does anyone have any recommendations for products from Ali?

    Looking to get some PV and LED combos for the garden etc. delivery times aren't as important as cost at the moment.


  • Registered Users Posts: 735 ✭✭✭ wannabecraig


    Thanks and sorry for late reply. I dont own a car, and so no old battery but I'll sort something out.
    Do you recommend anything that's a little better, happy to pay more obv.

    So, forgive my lack of knowledge, what lights would I plug into this?
    Also, is it safe to keep battery and charge controller in a wooden shed?


  • Registered Users Posts: 42 wavert


    You could go with something like this:
    https://www.ebay.co.uk/itm/312495514912

    You will also need some extension cables to run from the panel to the charge controller. Ebay or Amazon.

    There are loads of options for charge controllers similar to the one linked in the kit above - eBay or Amazon.

    If you don't have an old car battery you could go with a mobility scooter battery. These are suitable for cyclic charging and discharging. Halfords stock but at the moment they are closed.

    If you want to connect lights you will need some 12v LED lights. These then need to be wired back to the charge controller. You can put a day/night switch (linked above) or a manual switch somewhere between the charge controller and the lights.

    I have very similar solar panel to the one I linked fitted to a Wooden shed. I run three strip LEDs off a mobility scooter battery without issue. I do also have a timer and a day/night sensor. I have since removed the day/night sensor as it continuously pulls power. A larger battery would fix this but a bigger battery =$$$.


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  • Registered Users Posts: 735 ✭✭✭ wannabecraig


    Thanks, looking at This. Has the controller and cables.

    Perhaps you can provide options for lights? Is there a universal connector? So I can swap in all diff kind of lights?

    I see the 'lights' connector, but what does that connect to? Is there a panel that has a few light adapters?

    Also, the 50w one doesn't see to come with the crocodile clips, can anybody suggest ones I should get?


  • Registered Users Posts: 8,744 ✭✭✭ DaveNoCheese


    Sorry to dig up an old thread but I'm in a similar position to the OP.

    I need to power some lights in a garden shed / workshop at night and was thinking solar panels and a battery. I'm looking at this 40w panel from Amazon and will pick up a used car battery locally.

    Any recommendations for lighting then? Am I better getting a few LED spot lights or LED strip lights? Are these easy to set up and connect to the charge controller?

    Also, is the 40w overkill for just lights?

    Thanks in advance!


  • Registered Users Posts: 407 ✭✭ phester28


    The ball is in your court for lighting as there is just too many options. I have used a few cheap led strip lights from aliexpress at 1-2 euro for 2 or so meters of lighting. The lighting output as shown in the link will allow a light load to be connected. These cheap chinese charge controllers are to be tested as they are rough and ready. The voltage they read is often off and you cant calibrate it. That said they only cost about 5-8 euro on aliexpress so with some basic testing a cheap solution can be found.

    I believe some of these controllers have a after dusk setting that allows you to power lights for x hours after solar stops. That may be of interest or you could put a 12V PIR sensor from the load output and use that to allow you to trigger your lights for x time 30 sec to 30 min

    Lots of variables here but if you get a car battery for free and pick a suitable panel then the rest will fall into place

    Again be careful on the ratings some aliexpress solar panels show. They are just made up watts. I would go for a non flexible panel as flexiable dont tend to last more than a few years before developing issues....from what I've read.


  • Moderators, Category Moderators, Motoring & Transport Moderators, Regional East Moderators Posts: 58,822 CMod ✭✭✭✭ unkel


    phester28 wrote: »
    Again be careful on the ratings some aliexpress solar panels show. They are just made up watts. I would go for a non flexible panel as flexiable dont tend to last more than a few years before developing issues....from what I've read.

    +1

    I have a few flexible panels from AliExpress here. Rated 100W and most I got from them was 11W :p

    I gave out hell about this and got my money back. I also have some 25W rated hard glass panels and they give out the full 25W. As do all my other panels, I have 290W, 300W and 310W full size panels. All producing 100% of their rating.

    "Wind is Ireland's oil" - An Taoiseach, 25/05/2022



  • Posts: 0 [Deleted User]


    Flexible panels are not UV stable!!!!!

    300W domestic panel ~32Voc, 15A or better Morningstar PWM, 24v flooded lead acid, yellow Xantrex or Studer inverter, cable, switchgear. Job done.]
    You can buy all of the above used because they're bulletproof. [edit; well not the battery or the switchgear...]
    For just lights lose the inverter and get 24v strip and put it on the controller LVD terminals.

    I wouldn't say 40w is overkill...I'd say it's a complete waste of money. They're extortionate for a feeble output.

    Cheap charge controllers cost batteries.


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