How do self-cleaning water bottles work?
How it works: 15-second answer
Self-cleaning water bottles use UltraViolet type-C (UV-C) LED technology to eliminate 99.9% of bacteria, viruses, and bio-contaminants. A UV-C light module, located under the cap, emits light at a 250 nm wavelength, destroying the DNA of harmful microorganisms. A sensor ensures the bottle is sealed before the cleaning process begins.
How do self-cleaning water bottles work?
Relevant Components
1. UV-C LED module
An LED circuitry that emits ultraviolet light of type C (wavelength around 250 nm) is placed underneath the bottle cap, attached to it.
This is the primary component of the cleaning process, and it neutralizes the germs in the water. Also, using UV-C light is a medically proven technology being widely deployed in hospitals to decontaminate rooms.
2. Water Bottle
Of course! :D
The cap of the water bottle which has the LED circuitry we just discussed can be charged using a USB cable. The bottle also acts as an insulator, maintaining the water's temperature for a couple of hours. Moreover, a ring light on the bottle cap shows different statuses of the bottle (The green light is steady if it’s fully charged). A single charge will last about a month, apparently.
Figure 1: Charging the bottle cap. Source: Wellrigged
3. Photodiode-like sensor
A sensor detects if the cap is fully closed and ensures the absence of light within the bottle before it starts the cleaning process.
Working Mechanism
The bottle can self-clean itself every few hours. Or, you can also manually press a button to initiate the cleaning process, which would take 60 seconds in normal mode.
Ultraviolet light is used to eliminate 99.9% of bio-contaminants, viruses, and bacteria. UV disinfection technology destroys the DNA of microorganisms, leaving them dead and unable to grow further. The type of UV rays that work best to purify and clean water is UV-C (Ultraviolet rays with a wavelength of around 250 nm). This is determined after testing several times using different wavelengths of UV rays. Only UV-C can effectively kill the DNA of the pathogens.
Figure 2: UV-C LED module under the cap
1. Ensuring a water-tight bottle during cleaning
The photodiode in the water bottle generates a voltage when it’s illuminated, as it is a photo sensor. This is processed by the circuit and the cleaning process is not started when it detects light, as the bottle should be fully closed when the UVC is turned on. These rays are harmful to humans. Basically, it is assumed that the cap is not closed when the photo sensor detects any light.
2. Self-cleaning aspect
The UV LED setup in the cap emits UV-C rays when the button on the top is pushed. To fully clean the water, the interior of the double-walled bottle is designed to reflect the UV-C rays as the light can only travel in straight lines. Also, every few hours, the UV-C LED module automatically emits light to filter the water bottle in a few seconds. The ring light shines blue during this process.
And this is how it works!
