Alfredo Moser

Alfredo Moser is a Brazilian mechanic, and the inventor of the solar bottle bulb, known also as the ‘Moser Lamp’, or the PET bottle lamp.^[1][2] His invention led to the creation of the open-source organization Liter of Light, which offers sustainable lighting to families without electricity access in over 20 countries worldwide.^[3]

Early Life

Moser was born in rural Santa Catarina in 1951 and began his life working as a farmhand.^[4] He later moved to Brasília, where he worked as an auto mechanic. In 1978, he married his wife Carmelinda and then moved to Minas Gerais, settling with his family in Uberaba by 1980.^[5]

The Moser lamp

Conception

According to Moser, his inspiration for the invention emerged as a DIY solution in response to the blackouts during the 2001–2002 Brazilian energy crisis. However, its conception dates back over two decades earlier to his tenure as a car mechanic for a telecommunications company in the late 1970s, which was responsible for overseeing issues related to plane crashes in the Amazon region. During a specific instance, while discussing with his supervisor the challenge of not having means such as a matchbox to start a fire, given the prolonged rescue times in that area, his boss shared with him the technique of placing a small amount of water in a white bottle on the ground, stating that when the water is exposed to sunlight, it could generate enough heat to initiate a fire.

Years later, while overseeing his own workshop, Moser conducted experiments with water-filled bottles positioned on the roof of a dimly lit room. He noted that sunlight refracted through these bottles effectively brightened the otherwise dim space. Later, he started integrating bleach and polyester resin to improve his experiments.^[6]

Usage

After publicizing his findings, Moser was invited to speak at educational conferences. His invention was later embraced by open-source organizations like the MyShelter Foundation in the Philippines and has been replicated since 2012 through the Liter of Light project, which distributes sustainable lighting across multiple countries, benefiting impoverished communities lacking means or access to electricity. The project has further developed a method based on Moser's original invention, utilizing solar panels to power the bulbs. These panels are used in domestic installations and to illuminate streetlights throughout the night.^[7]

In 2011, Illac Angelo Diaz, Executive Director of the MyShelter Foundation, reported that Moser's invention was in use in approximately 140,000 homes in the Philippines alone. Additionally, residents in impoverished areas were able to cultivate crops on small hydroponic farms using the light provided by these bottle lamps.^[8] By 2014, Liter of Light had installed Moser lamps in over a million homes worldwide and expanded its reach across the Americas, Europe, Asia, and Africa by 2017.^[9]

Functionality

Moser's lamp functions without external power, using a plastic bottle filled with water inserted into a hole in the roof. It harnesses sunlight through refraction, providing illumination comparable to a 40 to 60 watt incandescent bulb when sunlight strikes the bottle outside. Below the roof, the sunlight interacts with chlorinated water, changing the light's refractive index and scattering it to effectively illuminate the interior.^[10]

Principle

• Sunlight is refracted through a water-filled plastic bottle, acting as a lens to focus and disperse light.
• The bottle, containing water and a small amount of bleach, is securely installed in a roof tile using polyester resin, ensuring it remains leak-proof even during rainfall.

Components and Installation:

• Bottle: A two-liter plastic bottle filled with clear water and two capfuls of bleach to prevent algae growth.
• Installation: The bottle is installed through the roof with its bottom facing upwards, capturing and refracting sunlight to provide illumination equivalent to a 40-60 watt bulb.
• Sealing: Polyester resin is used to fix the bottle in place, ensuring durability and protection against leaks.

Hybrid Moser Bottle (HMB) System:

• The HMB system incorporates LEDs for nighttime illumination, powered by solar energy stored during the day.
• This system is designed to provide approximately 3.5 hours of light for every 12 hours of solar charging, making it ideal for communities with consistent daylight hours.
• Modifications to the system can be made to accommodate different lighting needs, ensuring versatility and adaptability.

References

• This article draws heavily on the corresponding article in the Spanish-language Wikipedia, which was accessed in the version of 9/2013.