The Photo voltaic Bottle Lamp is a solar-powered mild that reuses a waste plastic bottle by attaching a 3D-printed photo voltaic lamp rather than the outdated plastic cap. It additionally makes intelligent use of the light-refracting properties of water!
I designed this lamp as a low-cost answer for lighting rural properties, changing their dangerous kerosene lamps and on the identical time upcycling a number of the thousands and thousands of waste plastic bottles which can be day by day thrown into the rubbish. These lamps are additionally nice for adorning a backyard, for tenting or touring, or for emergencies when the facility is out.
A Liter of Gentle
My design was impressed by the Moser bottle daylight lamp invented by Brazilian mechanic Alfredo Moser. The idea is that clear plastic beverage bottles full of water might be fastened into the roof of an unlit constructing to refract daylight round a room, equal to a 40W–60W bulb. In 2011, Illac Diaz used Moser’s know-how to begin Liter of Gentle, a grassroots motion to offer photo voltaic lighting to communities all over the world.
The Moser bottle is easy and cheap, but it surely solely works in the course of the daytime. So I designed a photo voltaic bottle cap that may present mild in the course of the night time.
How the Circuit Works
The photo voltaic lamp might be thought of as a standalone photo voltaic photovoltaic (SPV) system and comprises 4 fundamental elements (Determine A
):
• Photo voltaic panel — converts photo voltaic vitality to electrical vitality
• Controller — fees the battery (charger) and drives the load (driver)
• Battery — shops {the electrical} vitality
• Load (LED) — offers the specified mild output
The circuit, proven in Determine 
B on the next web page, might be broadly divided into two components. The charger circuit extracts energy generated by the photo voltaic panel in the course of the day and fees the battery. It’s based mostly on a TP4056 single-cell Li-ion charger module. The LED driver circuit powers the LED, routinely switches it on at night time, and controls the brightness.
Throughout the day, the photo voltaic cell generates voltage and turns ON the transistor Q2, so it doesn’t have the present bias to the bottom of transistor Q1. Q1 is OFF so the LED will exit.
When there is no such thing as a daylight, there’s no photo voltaic present to base Q2 so it is not going to conduct, however on the identical time, transistor Q1 will conduct. Now the battery’s present will circulation to the LED by means of the resistors (R3 or R4).
The three-pin button swap is used to attach both R3 or R4 within the LED circuit. When the pole is related to R3, the brightness is Low (excessive resistance, low LED present) and when related to R4, the brightness is Excessive (low resistance, excessive LED present). You’ll be able to be taught extra in regards to the circuit in my video.
Bottled Sunshine
Take pleasure in your new Photo voltaic Bottle Lamp! You may make a number of comparable bottle lamps and place them round your backyard or garden.
Cost it
• USB charging — Earlier than the primary use, it’s endorsed to cost the battery. You’ll be able to simply cost the lamp by means of a micro USB cable by connecting it to any USB energy supply like a telephone charger. The purple LED signifies that the battery is charging and the blue LED signifies charging is full.
• Photo voltaic charging — You may also cost the battery by putting the bottle lamp in vibrant daylight for a minimum of a day (Determine S
).
TEST IT
Press the button swap to set the specified brightness (Low/Excessive) and take a look at the lamp by masking the photo voltaic cell along with your hand. The sunshine ought to be turned on (Determine T
)!
Place the bottle lamp within the vibrant daylight, and the photo voltaic cell will cost the battery. When the solar goes down, the lamp will likely be routinely switched on (Determine 
U).
MODIFY IT
• Weatherproofing — You’ll be able to apply epoxy spray paint on the joint of the 3D-printed enclosure to make it extra water-proof. Apply conformal coating to the PCB to guard the board and its elements from the setting and corrosion.
• Simpler construct — Use a PVC-wrapped battery with its personal JST connector to keep away from use of terminal plates.
• Gentle mods — Add some cleaning soap answer to the water to diffuse the sunshine extra, or add meals coloring to make the sunshine coloured.
• Roof mount — To mild a room or shed, you may comply with Liter of Gentle’s directions for mounting the lamp on the roof.
Undertaking Steps
