A fascinating and informative podcast from TSP. Steven Harris goes over a lot of info about the differences in batteries. Steven Harris on Battery Back Up Systems Part 1 of 2 | The Survival Podcast What is being built:
interesting setup....but I would have thought that there would be more lumens to the watt by using an LED array than a single incandescent light bulb.
There would be, but a single LED equivalent bulb runs between 35 and 90 bucks! LEDs use a lot less power, but incandescents are dead cheap. On the other hand, Malibu garden lighting is 12VTdc and you can run a string of them for quite a while of a car battery. i have a simple solar/battery/ switched light string at our hunting cabin for the stairs in the dark. Works quite well at night.
Try LED Lights, Bulbs & Accessories - SUPER BRIGHT LEDS - I built a solar powered flood light using two standard 500 watt halogen fixtures (throw the bulb away), each containing 4 leds mounted on an aluminum bar for heatsinking. These were powered by devices available on this web site called a buck puck, which limits the current through the leds and allows controls, such as dimming (believe me, you need it!) The whole mess is powered by 4 twenty watt solar panels that I had laying around and I purchased two 12 volt sealed lead acid batteries 33AH each (pricey). They are connected in series (24 V system). Add a charge regulator and you have a semi-portable, powerful light source totally independent of cords generators or connection to the main solar power source. I also added a photocell control (on at dusk, off at dawn). So during the day, the batteries recharge from the solar panels and at night, the batteries power the light, which I leave on all night. It simply works, all by itself, automatically. With that size battery, I figured the light could run for about a week continuously, 24 -7 if there were no sunlight to recharge the batteries during the day. I use it on my remote property when I'm there. It covers about a 1600 - 1800 sq foot area with enough light to play horseshoes, and I didn't use the brightest leds available.
Sorry - New monkey here - Pic of lightstand. The large metal box near the bottom of the pole is a 40mm ammo can used to hold the batteries and charge controller. The buck pucks and photocell are contained in the 4x4 rainproof electrical box. The fixtures are held with 1/2" EMT rigid conduit. The center pole is 2 inch EMT rigid conduit ($13 at Home Depot for a 10 foot section, galvanized). The solar panel mounts are made from an old bed frame. The supports are angle iron purchased at the hardware store. If you look closely you can see the 4 LEDS in the fixtures. The LEDS themselves were about $3 each, but the buck pucks to run them are about $20 each. If needed, two more LEDS can be added to each fixture without changing any other components or wiring. As it is it's bright enough.
Early morning. The solar panels are adjusted to catch the late morning to full afternoon sun, although normally the batteries are nearly full charged by about 1:00 or 2:00 PM from an all night run. The switch on the side of the box turns the system off, runs the lights at full bright, or it can be set to dim. I run them on dim all night which provides enough light in case I have to get up and dispose of some beer.
