Joule Lamp

[Lynxsteam]

Lots of things you can do with this circuit.  You can also run your positive lead to the Joule lamp through a Torroid, 20 turns and have an isolated secondary of 200.  Off this isolated secondary you can power another bulb, CFL or LED, or even back charge the source battery.  I was able to reduce amp draw on one LED bulb by 20% back charging.  In effect its just diverting energy, but its interesting.

Here is my latest test with the Utilitech LED warm 7.5 watt bulbs.  The watt reading off the house grid was done through a watt meter and it is calibrated.  Please try this yourself and see that these bulbs consume more power than stated on the package, note that my grid voltage is 120 v and that may cause a higher amp draw.  The lightbox is a foil lined cardboard box with a 6 volt PV panel mounted 4" above the bulb lens.  The watt readings for the LJL is done by simultaneously noting battery voltage and amp readings off digital multimeters.  The bulbs are not moved throughout testing.

Note that in this testing the Deep Cycle 12 volt battery was between 12.87 and 12.89 volts while the lights were running.  This is due to the battery having been charged by an outdoor solar panel  for several days. 

I am discovering there are a lot of variables in how many bulbs in parallel, frequency, voltage, amp draw, brightness, two tiers of brightness... Notice in both cases the two bulb input wattage is more than twice the input wattage of one.  But in the house grid test, 2 bulb output wasn't as substantially higher than 1 bulb, as in the LJL case.

[JouleSeeker]

  Those are impressive results with the LJL, Lynxsteam. I like the approach of comparing directly with results from the house grid.

Very well done.

[Lynxsteam]

Thanks Joule Seeker, I am sure your test equipment is much better than mine.  I look forward to pushing the envelope for better performance from these circuits guided by your methodical and empirical approach.

I notice a lot of talk about the efficiency of the 12 volt LED bulbs.  That makes sense because they are designed for twelve volt DC.  What we are trying to do here is use AC which works better for whole house lighting as the voltage drop is much less with AC on long runs.  To get the same whole house performance from DC, very heavy gauge wire would need to be run and that costs $$$$.

It is also possible to design a SJR 2.0 to run one bulb very efficiently, but again my aim with this thread now, is to find an efficient way to run multiple bulbs, either permanently in a home or as a solar powered backup.  I find with the SJR 2.0 E-core that it is really good up to a certain number of bulbs (4-6) and then it self adjusts and wont put out more power.  My small E-core maxes out at about 5 watts.  You could simply have an E-Core mounted in each room with a battery.

The larger LJL Aircores I am experimenting with have hit 40 watts and I still need more bulbs to find the limit.  I also find paralleling more than five bulbs on a circuit is about right.    Down line paralleled bulbs after the fifth appear slightly dimmer.

If the AC is split into branches at the LJL it works better. 

I also think keeping this circuit as simple and foolproof as possible is the best way to go for under-developed countries.  Hopefully the price of LED bulbs will come down in price like digital watches did in the 1970's.

[b_rads]

Interesting those conversations of the going directly to dc lights has come up.  My wife does Arts and Crafts, Festivals, etc., and many times is outside without power.  I am building a simple system to provide some light for this purpose.  The light modules are rated at 0.9watts, however they are only pulling 15mA from my battery.  I should be able to power several of these modules on this system.  This should make a nice backup system for home as well as a functional outdoor light system. 

LED Lights
< $1.50 each

Solar Charger
$11.99 on sale â€" local pickup

12V 5AH Battery
$14.26 local pickup

My observation of the 3 different dc to ac inverters I have built.  Lynx Air Core â€" super easy, reliable, easy to start, very flexible.
RS 12V 450mA â€" Tricky for me to get started. 
Hand wound transformer with trigger coil â€" most efficient for a single bulb, most difficult build of the three.

Brad S 

[NickZ]

  Brad:
   Thank you for that recommendation, it does seam very practical. 
The Led company from Hong Kong also have other bulbs with higher outputs, but with relatively the same W/lm.  I've posted the link below.
  It looks like those one watt led bulbs placed in the different wattage bulbs, are the way to go, and especially at $1.50 or so, per watt, or less. As that is what just a single regular led (little ones) cost here. Magnetman was able to find the small ones on E-bay for just $4 per hundred, or so.
  Although totoalas had mentioned that the 5 watt panels were costing only $30 (including shipping), I had not found them at that price, until now. (link below).
5watt solar panel Monocrystalline cells 12volts | eBay


  The bulbs shown below also are very economical, and are 12v as well. Same company.
  It's going to be very hard to beat that market. Might as well join them, instead.
 
   
12V/110V-220V 3W MR16/ GU10 Warm/Cool White SMD/RGB/SpotLight Lamp Bulb Lighting | eBay