solar, just for lights

Inevitability

Inevitability

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<info>this thread spawned from the thread "running off a generator : why the UPS?"</info>
Ok, so the other thread got me thinking... maybe I should get a solar setup just for running the lights at home.

So, how do I go about this task? I'd appreciate your help/advice and checking of my calcs/assumptions...
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Power requirement:
Right now there are 10 light sockets at home running fluorescent bulbs. I'm gonna assume absolute maximums below...
20W lights x 10 = 200W max power.
200W x 6hrs max per day = 1.2kWh required per day
Let's call it 1.5kWh (with a power buffer)
To get 1.5kWh in 6 hours of sunlight, I'll need a 250W panel.
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Options?
- Can I just get 12V LED lights and power them directly off a battery? Advantages? Disadvantages?
- If I wanted to keep the CFL bulbs , I'd need an inverter right?
- Do I need a pure sine inverter for CFLs, or will the square / modified sine inverters work?
- What does a decent 200W inverter cost?
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Batteries:
- normally, I would think : "Car battery"
- what about this...
The_Traveller said:
<snip>
ask for LiFePO4 batteries as they will last forever.
Click to expand...
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Cost:
- 250W panel = R3k
- inverter?
- batteries?
- 12V LED bulbs which are equivalent of a 15W CFL?
 
Personally I would stick with the 240 volt as you would need to re look your wiring and switches if you run 12v DC to make sure they can sustain the currents involved with LED/CFL lights you may be ok but its another thing to work out.

We have run cfl's on modified sine inverters but they dont like it and dont last as long as they should so I would go with a pure sine inverter. You have also made the assumption that you will get the full 250W for a full 6 hours this is very unlikely but in your use case it is also very unlikely that all the lights will be on all the time.

The nice thing though is that you can add batteries/inverters/panels to the existing system so its not as if you absolutely have to be 100%certain of your needs as its easy to add more later on.

You also need a solar controller that can charge the batteries and protect them from draining too far but for a small system like this they are only a few hundred rand.

The best bet is to phone around and find a place with the best pricing on the big items and then go and have them put it all together for you. You also need to work on the DB board so you would need someone certified to install it all.
 
I am looking at doing the same, I need 200w if I switch on every light I have in my house, so I think I will get away with a 150w inverter. Going to wire into the Db with a change over switch for in case I run out of juice.

Beachless said:
Personally I would stick with the 240 volt as you would need to re look your wiring and switches if you run 12v DC to make sure they can sustain the currents involved with LED/CFL lights you may be ok but its another thing to work out.
Click to expand...

I looked at this, but the running 12v to anything with a decent wattage becomes a serious pain, the amperage goes so high you will basically need welding leads going into the house.

In the meantime I have installed a couple of LED strip lights, totals only 4w for the bathroom and lounge, so I am running it of a old alarm transformer and battery.
 
also interested to see this, mainly just want to power the plugs in my bedroom & a 12000btu Aircon :p
 
Personally I'd replace the lights with 5th Gen LED lighting (COB / Filament LED)

Average 6W power use per bulb for a 60W equivalent, and next to no heat.

Example 15630658753_38a0da5f78_o_d.jpg
 
heartbroken said:
Might be cheaper to build a pool than powering that beast from solar.
Click to expand...

http://www.sednaairesa.co.za/ just came accross these guys they do a specific solar aircon

Can one recommend some solar security flood lights. One where you buy a flood light with a small solar panel & battery that powers it. I see the average use is about 8 hours on a charge.
 
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lsheed_cn said:
Personally I'd replace the lights with 5th Gen LED lighting (COB / Filament LED)

Average 6W power use per bulb for a 60W equivalent, and next to no heat.

Example View attachment 191059
Click to expand...

I was quoted R215 for a 3W dimmable arora candle globe. It is equivalent to 40w.

I currently have 40W globes in my living room and it can get quite bright. (You'll be saving 3W lol :p)
 
They're a relatively new item - although the markup on that is roughly 500% odd (I know what they cost, and I know the import charges/ duties, so thats a heavy heavy markup).

I can bring in if people want to do a group buy.
I already brought a bunch and sold to others earlier this month.
 
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these led bulbs are too expensive. who has a big variety? I have found like for like replacements not to be the same. the lights are not as bright as the cfl's. the bayonets are hard to come by as well. going to makro and im hoping they have a bigger variety.
 
CamiKaze said:
I can get it for R215, yeah it's expensive...

22 bulbs for my living room alone.
Click to expand...
Well it doesn't look like money is an object for you then.

I don't think I will spend that much just for one room's lighting. Noddamoer!
 
OP, there are so many threads right now on inverters, batteries, solar setups etc. People, including myself, having given lengthy, detailed replies with calculations and tips in them.

Please search the forum and read all of them first as it has been repeated many times already.

Try these threads:

http://mybroadband.co.za/vb/forumdi...oad-Shedding-Generators-UPS-Alternative-Power

http://mybroadband.co.za/vb/showthread.php/677925-Buying-a-UPS

http://mybroadband.co.za/vb/showthread.php/678137-Inverter-recommendation
 
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