Living in Johannesburg, South Africa means that for security reasons it is advisable to have good lighting. Unfortunately we also have the most corrupt, defunct, useless and degenerative power utility on the planet, or so it seems. This means that with the constant unscheduled blackouts, rolling power outages (they call it Load-shedding!) and "Dirty" power caused by brownouts we tend to go through light bulbs with monotonous regularity.
After coming home from a business trip recently I was dismayed to find that all but one of the outside lights that run along my garden wall had blown. I was running CFL's to try and keep the electricity bill down whilst providing the security of the wall lights but they were proving to be more expensive because they would not last longer than 6 months.
In one of my past Instructables I had mounted a series of solar panels on my garage roof and I was now intent on using them to run a series of LED lighting along the wall. Coupled with a day/night sensor I was confident that I would be able to achieve my goal of reducing my reliance on the incumbent power utility whilst providing greater piece of mind with constant, reliable perimeter lighting.
Many thanks to Mick and Paul Clark from Aerospace Welding for the idea which I gleaned from viewing their (much more professional) efforts.
Step 1: Converting the Old Fittings
I didn't want to spend a ton of money on retail LED fittings when I had perfectly useable fittings already mounted and wired along the entire length off the wall. I decided that I would convert the fittings to handle a custom "Bulb" utilising some aluminium bottles that I had squirrelled away in my workshop. I was fortunate to work as a barman for a friend of mine, Mike, whom had just opened his pub and restaurant franchise "Hogshead". On an average weekend night we went through approximately twenty bottles of these sickly flavoured vodka drinks and I purloined the empty bottles every night knowing that I would find a use for them one day.
Step 2: The Reflectors
I cut the tops and bottoms off of the bottles with my bandsaw and then split them in half to provide me with enough parabolic reflectors to do all of the lights. You will notice that some of the bottles were coated in a clear protective varnish whilst others had a white (titanium oxide?) coating to stop the taste of aluminium from affecting the drinks. I didn't bother with removing this and left them as they were because I didn't think that it would make a difference to the reflected light.
Step 3: Prototype
In my last instructable about the solar panels I showed you the light that I had converted to 12volt CFL that was then running from the solar panels and battery banks and promised that I would do an instructable on that conversion and the day/night sensor build. Unfortunately time and work locations meant that I was never able to get around to that.
Here though I use that rig so that I can test different quantities of LED strips so that I could judge the output and test the ability of the day/night sensor to run the LED's instead of the 12V CFL that I had in there previously. I ended up running three strips of 9 LED's in each. I was very impressed with the outcome and the performance of my home made reflectors.
Step 4: The LED Strips and Stuff
To do the whole wall I needed multiples of everything. It is always tedious to repeat the same process over and over again but there is nothing much else you can do but bite the bullet. Setting up a production line and churning out each component to a ready state is the only way to do it. I ended up sitting on my bed with my craft board in front of me whilst I methodically cut and stripped all the LED lengths and the positive and negative leads for each length of LED whilst watching TV.
Trying to get the red and black wires soldered to the correct side of the trimmed LED strip proved to be a mind numbing job that you needed to concentrate on otherwise you ended up mindlessly soldering the lead onto the wrong side. ZZZZZZzzzzzzzzzzzzzz.......
Step 5: Building the "bulbs"
In some of the "bulbs" I used three lengths of LED's and in others I used two just so that I could see the performance difference. There wasn't one! If I ever do this again I will only use two strips in each bulb as the reflectors worked so well that there was no need for the third strip. The main picture to this instructable has a mixture of lights with 2 and 3 elements in each and I dare anybody to tell me which ones are which.
Each bulb was wired to the electrics that ran the length of the walls and the electrical cable was disconnected from the mains power supply (240V here in SA) and was connected to the Day/Night sensor that was supplied from the battery bank in the garage that was in turn charged by the solar panels on the roof that can be seen in my previous instructable.
Bulbs were attached to the light fitting using a Glue gun to gain a temporary purchase and then I used "No More Nails" poured in to the top crevice so that the marriage was permanent and would not be affected by heat.
Step 6: Cost
Besides time, there was very little cost except for the LED strip. Each 5M reel cost me just under R500 which is approximately $50 and various bits and bobs such as the connectors and glue were probably another R200 ($20). The Day/Night sensor kit was R100 ($10). So for less than $100 the value of my property is increased, I have safety in the form of light and I have a good green energy solution. The lights have been coming on at dusk and going off at sunrise for over 3 months now with zero maintenance or fiddling.
Well worth it. So worth it in fact that I even gave my house number the same treatment, but that is for another instructable some other time :-)