Even I go to Chill and Grill with my team, Harshad Khadilkar, Zainul Charbiwala and Deva Seetharam, and Rajesh Kunnath and Deepak Ramakumar, and colleagues from our hardware partner, RadioStudio. We had an idea for Lalit.
By using discarded laptop batteries, we created a device that could power lights, fans and mobile phone chargers. The specific prototype we built was able to provide around 20 Watt-hours of energy. In other words, it can power a 5W DC light bulb for about four hours before running out of charge.
The prototype of the device was built with help from RadioStudio. It took four steps:
- Source laptop battery packs through organized electronic waste (e-waste) collectors
- Disassemble the packs to extract individual cells that could still deliver power
- Connect re-usable cells together to build a refurbished battery pack
- Build a box that contains a charging circuit for the pack of refurbished batteries, converters, and other electronics to power the external devices such as lights and fans.
We estimate the bill of material for the device to be about Rs1000 (about $US16.50) each, when compared to conventional backup solutions such as inverters and diesel generators which usually cost upwards of Rs 10,000 (about $US165). The pricing includes the enclosure, electronics, DC fan and an LED light.
Having installed the device at Chill and Grill, we found that it was able to provide about four hours of backup power when the batteries were fully charged.
Our team also believes that several variants of the device are possible depending on economic and technical feasibility, such as inclusion of a mechanical battery rack instead of a small battery pack; a low battery cut-off indicator; dead battery cell indicators; and the use of other types of battery packs such as cellphone batteries. And we’re also exploring solar energy charging.
The device attempts to mitigate the environmental and economic issues associated with e-waste by providing a means to re-use discarded batteries. In particular, if this technology is adopted commercially at a large scale, it can incentivize organized collection of e-waste. A large chunk of e-waste collection in India is still handled by the informal sector consisting of local garbage dealers or kabariwallas, which is currently unregulated and poses safety and environmental problems.
Back at Chill and Grill, Lalit has been happy with the amount of light he can get from his device. My team is confident that the device will be made commercially available and widely adopted.