Solar help needed.

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Brambles
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Re: Solar help needed.

Post by Brambles »

Cheers, gives me somewhere to start. :) A trip to the caravan shop in town on my next day off it is then. :D
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Yorkshire Andy
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Re: Solar help needed.

Post by Yorkshire Andy »

If you find the fittings you like see if there's a 12v led bulb to suit eg

https://www.atenlighting.co.uk/caravan- ... e-lighting
If your roughing it, Your doing it wrong ;)

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ukpreppergrrl
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Re: Solar help needed.

Post by ukpreppergrrl »

I think you can use bog standard fittings, just fit 12v light bulbs (and appropriate plugs/connectors). The fittings are just wires and a holder. With the small amperage involved in, say, 12v 5w bulbs (0.416 amps if my maths is correct!) the twin or twin and earth wiring used for mains lamps should be fine. (Caveat: I am not an electrician and may not know what I'm talking about!)
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yorkshirewolf
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Re: Solar help needed.

Post by yorkshirewolf »

I might be able to help a bit, i've worked on camper vans and caravans so have installed a bit of led lighting on solar.

Firstly, how big is the room and how high are the ceilings? most 12v led bulbs/strips are very bright but the light fades from about a metre, so it's great in small spaces but not so good in a big room.
The newer CREE type led is a lot brighter and gives more light spread over distance but uses a lot more power.

Main things to look at are watts and amps, and how both work, this will make it easy to work out what you can run and for how long.

Have a look here: http://www.newelectric.com/whats-the-di ... and-watts/

There are a few different types of 'on-the-roll' led strip- 5050, 3528, 2835, this is the amount of individual leds per metre, and power usage can vary from 1-2amps per metre to 7-8 amps per metre.

Lets say you go on ebay and buy 5 metres of 2835 light strip, which will be about 50watts, this will pull about 5 amps for the full 5 metre length, this will use 5 amps per hour, or 5 amp hours (usually written as 5ah)
And lets say you have a 120ah leisure battery, now you can't run any battery down 100% or it won't recharge, so lets play it safe and run it down to 30% before it charges, this gives you 84ah, which means the light strip will run for 16.8 hours from the battery without any solar or other charging.

So, now lets say you have a solar panel which is 100w, this will put about 5amps into the battery per hour, in good bright sun, so through a sunny day, it will charge the battery enough to run the light strip overnight.

Or, you can buy the enclosed 40cm long led light strip fittings found in most caravans/motorhomes, these are generally very low power, maybe 3w, so will use less power (0.25amps) so these will run forever!


Try using this calcuator: http://www.rapidtables.com/calc/electri ... ulator.htm

You'll be using a 12v DC setup, so it's an easy way to work out what will run and for how long.

HTH :)
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Brambles
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Re: Solar help needed.

Post by Brambles »

Cheers for that. :) Not sure I want the strip lighting, it's all in my head atm :shock: :lol:
Life isn't about waiting for the storm to pass, it's about learning to dance in the rain~anon
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yorkshirewolf
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Re: Solar help needed.

Post by yorkshirewolf »

Brambles wrote:Cheers for that. :) Not sure I want the strip lighting, it's all in my head atm :shock: :lol:
I'd actually avoid the rolls of led strip, it looks bright but would be rubbish to light a room, and it uses a lot of power for what it is. For fancy bling and show vehicles, great, but not for emergency or room lighting.

Is this going to be permanent and used every day? Or just emergency lighting Brambles?
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Brambles
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Re: Solar help needed.

Post by Brambles »

yorkshirewolf wrote:
Brambles wrote:Cheers for that. :) Not sure I want the strip lighting, it's all in my head atm :shock: :lol:
I'd actually avoid the rolls of led strip, it looks bright but would be rubbish to light a room, and it uses a lot of power for what it is. For fancy bling and show vehicles, great, but not for emergency or room lighting.

Is this going to be permanent and used every day? Or just emergency lighting Brambles?
For my next property I want all the rooms to be 12V Solar powered except the kitchen. That will be 240V mains. My first thought was to design a lighting system only, then I thought I could perhaps extend it to the power sockets too. There's a lot of 12V stuff out there and I want to be as off grid and power self sufficient as poss without going down the grid tied solar route. I'm looking at a 500W solar set up with batteries. Just thoughts in my cheapskate head. :) I also understand 12V solar systems, sort of!

My dream would be totally 12V solar and completely off grid but I'm realistic, if I want the comforts of a washer/dryer, fridge/freezer and a quick boiling kettle then I'll need mains leccy.
Life isn't about waiting for the storm to pass, it's about learning to dance in the rain~anon
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yorkshirewolf
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Re: Solar help needed.

Post by yorkshirewolf »

The problem with 12v systems is that whenever you run anything of high ampage it smashes the batteries, wether directly 12v or through an inverter.

It's doable to run household lights on a 12v system, wether solar or through converters, and you can certainly use 12v to charge or power most technology, it's the cost that starts becoming an issue, you need lots of high Ah batteries to store the energy and the means to recharge them, which in the UK can be problematic as the weather is a bit unreliable...

the newer types of 240v LED bulbs are very good but are designed to run from 240 only, i've been replacing bulbs as they go with the new LED types, in fact i recently replaced both bedside lights with LED, went from 40w bulbs which got very hot to 4w bulbs which have a nicer light, run cool and use 10% of the power!
Obviously no good in a power cut but i have the rechargeble LED worklights for that as well as torches, candles etc.
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Brambles
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Re: Solar help needed.

Post by Brambles »

I have in my mind what I want. An acquaintance has a barge and is totally off grid on a 12V system using a 500w solar set up and runs the engine when they need to do the washing! That's their only 240v item. I am pretty sure I could do the same in a house.
Life isn't about waiting for the storm to pass, it's about learning to dance in the rain~anon
Appin
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Re: Solar help needed.

Post by Appin »

As with others there are commercial options available

http://www.gooutdoors.co.uk/hubi-2k-p367097

http://www.gooutdoors.co.uk/hubi-10k-p367087

Actually a book called Emergency Power for Radio communications by an American called Michael Bryce is well worht a look. He has a whole chapter devoted to "keeping the lights on" including why you may not want to have light.

Regards

appin