Intro: This Instructable is about a novel evolution to an existing 'Solar Lighting' concept - originally invented by Brazilian engineer, Alfredo Moser, who's lighting invention (aka Liter of Light) has given free lighting to people in developing (and developed) countries through clever application of chemistry.
How it works:
- It does this by taking a bottle of water;
- adding a little chlorine bleach (c.20ml or 1%vol.);
- cutting a hole in the roof (often corrugated tin sheet);
- inserting the bottle half-way in and glue in place.
- The light from the sun hits the external half of the bottle;
- the light bounces around in the chlorinated water - and 'glows';
- (the chlorine changes the refractive index of clean water, 'partially trapping' the light);
- the internal half of the bottle glows with equivalent light to a typical 55W bulb.
So what's the innovation, here?
- The above only works in the daytime - this 'evolution' also works at nighttime...
- It uses LEDs to create a 'glow' in the Moser Light at night.
How it started: I was part of a team at a Power Hack Workshop looking to develop Off The [power]Grid solutions for electricity in developing countries. We loved Alfredo Moser's invention - but realised it would not work at night. So we wondered if combining it with an LED would make it a great night-light. (And you can appreciate that an evenly dispersed light in your room is nicer than a harsh, dazzling LED).
At the time when Moser developed his light c.2002, the price of LEDs were far too high for developing countries to afford - especially the super-bright kind you get today. However, with charities like Practical Action and Liter of Light exploring new opportunities with the falling price of various technology, LEDs might start to become realistic. Clearly there is lots of questions still to resolve, but I'd appreciate constructive comments from the Instructables community which might help progress this concept.
How this Instructable is set out:
PART 1: How to Make an LED Moser Light.
PART 2: Behind the Scenes: (How we arrived at this idea, and some concepts on generating the electricity (off grid) to power the LED in the first place).
- Please note this Instructable is of my own initiative, and the views expressed here are my own and do not reflect that of the companies mentioned.
- However, in the event of a win in a Contest (here's hoping - please vote!) - naturally, I would donate the winnings/prizes to the charities listed above.
- Usual H&S disclaimer: Be careful, Chlorine/Bleach is nasty stuff - it can damage eyes, skin, clothes, etc. Wear gloves, eye protection and a mask if sensitive to fumes. Read the instructions before use. I'm not responsible for any harm caused by following this Instructable.
Step 1: PART 1a: Making a LED Moser Light
You will need: 2 Ltr Bottle, Epoxy Glue, Drill, 12V Super Bright LED, wires, Battery/Solar Cell...or even your own Power Generator (see Part 2).
1. Add 2 capfuls (~20ml) Chlorine Bleach to your empty 2Ltr water bottle.
2. Fill up with Water. Stand aside and allow to mix/disperse.
3. Take your Bottle Cap. Drill a hole in the middle (wide enough to poke LED wires through).
4. Wire-up your LED* to some cable. Thread through Bottle Cap.
5. Mix up some Epoxy Glue. First glue the LED in place and spread the glue out (but not over) the 'rim'. Allow to dry. In the unlikely case that this 'rim' does not exist in your country, just take care to not go right to the edge - you will see why from the diagram.
6. Mix up some more Epoxy Glue (Super Glue will also work). Glue the other side, sealing the hole and fixing the wires in place. Allow to dry.
7. Take your 2Ltr Bottle and LED-Screw-Cap Assembly together.
Step 2: Part 1b: Installing Your LED Moser Light
continued...
8. If you are confident in your gluing/sealing - mount upside-down, if not, keep it the normal way up and it will not leak, but remember you need another hole to run your cables through the roof as well.
9. You can now your LED Moser Light in your roof the same way as illustrated in the video, or just hang it in a convenient place inside if you just want to run off battery power.
10. Finally, if you are curious to see what other ways of powering this LED we came up with read on to PART 2... *You might want to add search terms such as COB (Chip on Board) and SMD (Surface Mount Device) in your 12V LED Google-searches. Although these do get hot, they are 'cooled' by the water and are very bright.
Step 3: PART 2: Behind the Scenes: Generating Off-the-Grid Power (for Your LED Moser Light)
Electricity generators are nothing new, they convert rotary mechanical energy into electrical energy. For the Power Hack Workshop we took a Wind-Up Torch and made housing for it to function as a 'Hub' for things which would make it spin. We proposed two 'turbines' that would power this generator:
A. Using Aluminium Cans to be cut into turbine blades - for windpower.
B. Using more 2Ltr Bottle as 'scoops' or 'paddles' - for water power.
Arguably a whole range of issues remain unresolved, from the mechanical to logistical, when designing for low-cost Off-the-Grid power solutions. It will be interesting to see where this project goes. Please take a look at the video of the presentation - and feel free to give any support to this project or the charities involved.
Step 4: Appendix: Resources
Much of this workshop was done with Designers and Engineers, and it assumes a fair bit of knowledge of how to make proof of concept models. I happen to run a website dedicated to sharing knowledge on prototyping, I call it Design Modelling and you might find it useful if you wish to create any of the models you have seen here.
Best wishes,
Jude
Power Hack (RS Blog): http://www.rs-online.com/designspark/electronics/e...
Practical Action: http://practicalaction.org/energy
Liter of Light: http://www.litreoflight.co.uk/
Design Modelling (my Blog & contact details): http://www.judepullen.com/designmodelling/electric...
How to make waterproof prototypes out of Correx: https://www.instructables.com/id/Make-Waterproof-Pr...
Update: Moser Related Instructable (woo!): https://www.instructables.com/id/Day-and-Night-Time...

Fourth Prize in the
MAKE ENERGY: A US-Mexico Innovation Challenge
48 Discussions
4 years ago on Introduction
Thanks for all the amazing comments!
I'll be passing these on to A Liter of Light, who are working on next generation Solar Powered Water Bottle Lights.
http://aliteroflight.org/
https://twitter.com/aliteroflight
4 years ago on Step 3
Amazing Idea, I just came to the same solution for the bottles. Do you have a 3D Model for the Motor-Bottle Assembly part?? Thank you and greetings from México City
4 years ago on Introduction
Great work. I've came up with a cheapy version of "liter of light project" Will post at some time. Like your use of faraday principle Keep it up!
4 years ago on Introduction
It's lovely but please there's an important detail. Blue-ish white light at night is a health hazard, so don't use regular white leds, use low CCT (eg 2700K, 3000K) instead. (your brain responds to blue-ish white as if it's daytime).
Here's one link, but I can give you tons more info if you want to follow this up. It would be really bad to inflict a range of first world diseases when trying to alleviate third world hardships.
http://www.ama-assn.org/ama/pub/news/news/2012-06-...
Reply 4 years ago on Introduction
Thanks for the comment. I had heard about these claims and appreciate blue-white light is far from relaxing. Certainly one to keep on the design spec.
4 years ago
Well done and presented.
What about tonic water? It is prevalent wherever malaria is present. The quinine reacts quite well under black light. Use an UV LED.
What about corrosion from the chlorine? Long term testing required.
If you can't put holes in the sheet metal panels, wedge it into the seams or the southern wall.
Reply 4 years ago on Introduction
Or northern wall, when accessible, in southern hemisphere. :o)
Reply 4 years ago on Introduction
Thanks for the comments. Indeed, some good 'testing' has been done with http://aliteroflight.org/ take a look. As for UV and quinine it's an interesting one to test - do pass it on!
4 years ago on Introduction
I must say this is a beautiful, elegant idea.
But not useful in the Third World. Being born and grown there, I can tell you that having an electricity generator (or an electric motor that could be adapted) is something that a person living in a small hut with corrugated metal sheet cannot afford.
Reply 4 years ago on Introduction
I guess the question seems to be about the varying levels of poverty and industrialisation. I certainly would not claim to challenge your experience, but I guess there is an interesting movement around these NGOs around trying to look at cost, distribution and other realities. I imagine there will be a tipping point where altruistic/charitable initiatives will hopefully disengage when local economies are sufficiently established around worthwhile products to solve issues like this. I suspect building economies is more valuable than just hand-outs in the long term. I'm sure there is much ethical debate over whether industries like Mobile Phones in developing countries is empowerment or entrapment, but obviously this would be aiming at the former. How effective it is, is yet to be seen. Thank you again for your comment and contribution.
Reply 4 years ago on Introduction
Let me add a couple of comments:
- I worked ten yrs. long for an NGO around very poor neighborhoods, before moving to Europe. I can only agree with your comments.
- I see your idea as a good beginning for a community project. What's financially not possible for an individual could be reached by a group.
- This brings other issues, more social than technical or financial, regarding cooperation and assuming together advantages and disadvantages (E.g.: wind generator is never that silent). It's part of the game, for sure.
- I know people still working in this direction that could work out an e-generator based on recycled pieces. I'll pass them the idea.
Thanks a lot for posting it!
4 years ago on Introduction
sadly it's all about cost - the advantage of the non-wired bottle lights is that they costs almost nothing, and having light in a windowless shack or back room 10 or more hours a day is a real advance. The next step up for the third world (I work mainly in Haiti) will probably be the 'solar light bulb' concept where tiny panels are built in or come pre-attached, to charge in the day thus giving 4 or 5 hrs of light in the evening to do homework etc. The cost of a wind generator or solar panel and battery, wiring, and the level of technical education makes this type of solution inaccessible - a shame when one 50W panel might power a village of 20 houses if they were close together...
Reply 4 years ago on Introduction
Hi mandythody, Very interested to hear about your experiences in Haiti. You may also want to reach out to Illac Diaz (http://aliteroflight.org/) who is mentioned in this blog, and is working on exactly what you suggest - in fact it's more V2.0. Thanks for your comment.
4 years ago on Introduction
I would suggest taking the LED and sanding it lightly so the plastic becomes white. this will help spread the light more evenly on the medium and make a stronger bound with the glue since the surface is not smooth anymore.
Perhaps you don't even need the medium at all if you simply sand the bottle as well. Or you could use only water instead of having to deal with the risks of working with bleach. That would have to be tested out to find which is better tho.
Reply 4 years ago on Introduction
Good shout in the sanding. Noted. Thanks!
4 years ago on Introduction
Minor change... instead of drilling a 5mm hole for the LED, drill two 1mm holes... then push the LED in from the top. The LED is less likely to get pulled loose, the seal wil be better, and the LED will sit slightly higher in the assembly.
Reply 4 years ago on Introduction
Minor Wins are what this stuff is all about! I totally agree that this is a way smarter solution and better than tying a not in the wires, etc. Good shout. Feel free to take a look at https://twitter.com/aliteroflight if you have any more suggestions as good as this!
4 years ago on Step 3
The instructions are well done, and I'm going to try making one, to see how it fares in service. In thinking about the Hub part, would it be possible to 3-D print the part? This would make it easier to make replacement parts nearby, presuming a town would have a printer and filament handy... (Maybe the curves are too tight for the attachments for the fins/blades? I haven't tried 3-D Printing yet, I'm still reading about it.)
Reply 4 years ago on Introduction
As much as enjoy a good bit of 3D printing, I don't think we are expecting this to be the final concept, rather something injection moulded or fabricated in an even simpler way - the simpler and more robust, the better.
But for your own exploration, I'd certainly give it a go. There's a lot to be learned in CAD about how to manipulate the splines and get the right tolerances for a build. Have fun!
Make: have done a great review of 3D printers, in case you are interested. http://makezine.com/volume/guide-to-3d-printing-2014/
4 years ago on Step 4
Love it! Made some of these for our outdoor BBQ area. Proved to be quite a talking point.