Alot of this project in the net and very interesting. It remind me back some of my tennage project.

Here another website where more than thousand project you can choose -> http://www.instructables.com/

Just to share here is my project, 2 solar power spotlights for garden. Lighting time from 7PM to 6AM, 11-12 hours.

Components:-

1) 12v SLA Battery 7ah x 3 units (wired in parallel to provide 21ah, to be replaced with 100ah battery)
http://forum.lowyat.net/index.php?showtopic=1495775&hl=7ah


10 watt LED spotlight x 2 units (modded to work at 12vdc)


Solar Controller
http://www.mudah.my/SLD+T+Solar+Controller...or-11035638.htm


50watt Solar Panel from Solar Power Mart
http://solarpower-mart.com/yahoo_site_admi...ET.26875342.pdf


Misc Other Items
Outdoor wiring
Panel enclosure box
Crimping pliers and crimp head/lugs
Soldering iron
Shrink tubing/wiring tape
Testpen
------------- dan lain-lain!

I'll post picture of the actual setup later

This post has been edited by aaronpang: Jan 10 2012, 03:14 PM

May I know what kind of battery you are replacing? I m in a mis of looking for a battery.

The LED spotlight not come in 12VDC? I see mostly in 12VDC.

Base on my calculation usage of 10wx2x12hr = 240whr. Which require 1104whr battery bank capacity (92amp battery). But need 62.4w solar panel which mean 2x50watt solar panel. Provided 5hr sunlight and 2day backup.

By the way, is that lenglui from solar power mart? I m interest of her than the panel.

damn you guys just, provided all the stuff we need to change all external lights to sun powered..

@ozak so need to pia 5hrs 2 days backup ?

sun shine so little ?

the solar controller dont have input from AC ? as backup ?

5hr is max the sun shine on the panel at certain place. Some country have only 3hr. Not just the sun hr, you need the sun shine angle per your contry longtitude. And panel face south. The rest of the hr sun is not productive or less efficency.

The solar charge controller is for convert the V and A to stable charge the battery. For switching AC backup need another device.

The LED itself are DC, however spotlight from lighting shops work on 110 to 220vac.

When I open up the spotlight there is a a driver that converts mains AC to DC for the LED.

Replacement battery, single 100wh AGM battery from GP.

I picked it up over the weekend but it's not installed yet. Here is the shop I purchased the battery from:-

Volga Battery Specialist
46, Jalan Puteri 5/8, Bandar Puteri Puchong, Puchong, 47100, Puchong, Selangor
Tel 03-8060 5523
Fax 03-8060 5792
HP 016-927 6188

==========================================

Can you help me with this calculation 10wx2x1hr = 20whr.

20whr / 12v = 1.6AH is that correct?

Currently 21AH battery lasts approx 4 hours before lights out, I'm wondering why the battery doesn't last much longer

This post has been edited by aaronpang: Jan 10 2012, 05:35 PM

The calculation should be correct. That is possible your battery not fully charge. And the battery cannot be use till 0 charge as it will shorten the battery life. To makesure the battery last longer, you cannot discharge more than 50%.

Another possible is your spotlight maybe run more than 20watt.

Thanks ozak for the confirmation, it's likely the controller cut-off preventing batteries from deep discharging.

I'll get a multimeter to verify if battery voltage drops too low.

My another mini tiny solar power light project for CNY. He...

Use 2pcs solar light and modify it to power 2pcs tanglung at the car porch. The tanglung light is 2pcs LED which probably 0.6w. Once the sun down, the light will up till next morning and the solar will charge the battery again.





This post has been edited by ozak: Jan 11 2012, 01:48 PM

Nice job re-purposing the solar tanglung lantern, originally what are the lights used for?

Just sharing pictures my installed system, pardon the crappy phone cam pictures.















I didn't know until I collected the battery, it's extremely heavy!


Hope the photos are useful and will motivate others to give solar power a try.

Small scale project like those pictured are easy to setup

This post has been edited by aaronpang: Jan 11 2012, 03:34 PM

How much is the 100AH battery? Why not get a normal Car battery? Say 2x NS60? Will it be cheaper? Or N100

Original of this solar light is a door entrance or garage light. It use motion and day/light sensor to activate..

---

Added on January 11, 2012, 4:15 pmCar battery can't be use for solar as it cannot discharge deep. And when use in solar, it have a short lifespan than the AGM battery.

This post has been edited by ozak: Jan 11 2012, 04:15 PM

Paid RM650 for the GP 100AH battery.

It's a good question, originally I wanted to use a car battery too.

Later I found out flooded lead acid batteries are not suitable for solar applications, same reasons per ozak's reply.

Also if stored in a sealed box, car batteries release flammable gas that can explode.

More info on AGM batteries http://en.wikipedia.org/wiki/VRLA_battery

In terms of lifespans AGM batteries, have longer lifespans.

Checkout the BMW club forums, AGM batteries last up to 5 years

By comparison Kembara batteries need replacing every 1 to 1.5 years

Source:- http://www.bmwclubmalaysia.com/forums/show...511-E60-Battery



=====================================

Found more info http://en.wikipedia.org/wiki/Lead%E2%80%93acid_battery

Starting batteries
Main article: Car battery

Lead acid batteries designed for starting automotive engines are not designed for deep discharge. They have a large number of thin plates designed for maximum surface area, and therefore maximum current output, but which can easily be damaged by deep discharge. Repeated deep discharges will result in capacity loss and ultimately in premature failure, as the electrodes disintegrate due to mechanical stresses that arise from cycling. Starting batteries kept on continuous float charge will have corrosion in the electrodes and result in premature failure. Starting batteries should be kept open circuit but charged regularly (at least once every two weeks) to prevent sulfation.

Starting batteries are lighter weight than deep cycle batteries of the same battery dimensions, because the cell plates do not extend all the way to the bottom of the battery case. This allows loose disintegrated lead to fall off the plates and collect under the cells, to prolong the service life of the battery. If this loose debris rises high enough it can touch the plates and lead to failure of a cell, resulting in loss of battery voltage and capacity.

[edit] Deep cycle batteries
Main article: Deep cycle battery

Specially designed deep-cycle cells are much less susceptible to degradation due to cycling, and are required for applications where the batteries are regularly discharged, such as photovoltaic systems, electric vehicles (forklift, golf cart, electric cars and other) and uninterruptible power supplies. These batteries have thicker plates that can deliver less peak current, but can withstand frequent discharging.[9]

Some batteries are designed as a compromise between starter (high-current) and deep cycle batteries. They are able to be discharged to a greater degree than automotive batteries, but less so than deep cycle batteries. They may be referred to as "Marine/Motorhome" batteries, or "leisure batteries".


This post has been edited by aaronpang: Jan 11 2012, 06:10 PM

Yeah, I know the Car battery problem, thought you only use 50% of the 100Ah.

What is the solar block you have? 100Ah full discharge take a large volume of solar block to recharge back in one day.

Anyone try some wind turbine? Can instal on the roof to generate some power. He...

Thinking some wind turbine project using some servomotor.

if i live in kampung sure install one

No need live in kampung 1. Make small small 1. Than decorate with some leaf make look nice on your roof.

yeah right

in before neighbour complain and MP what ever come and roboh kan...

Need very big fan to generate good electric

Have all this ingredient to make wind turbine lying around. Some spoil servomotor which can use as generator. But don't no how to make a rectifier and some electronicx component to stabilize the voltage.

Just evening try out direct connect with LED. Can light up a LED. But burn out later due to higher rpm.