Powering communities with discarded laptop batteries

By Vikas Chandan, Research Staff Member with IBM’s Smarter Energy Group

Located right across Bangalore’s Ramaiah College is Chill and Grill, a fast-food joint that is an easy jaunt for students as well as young working professionals who work in the area. The piping hot evening snacks such as wraps and samosas attracts large crowds. And business has been growing for Lalit, 39, who has been running the eatery for more than five years. While business is good, he’s had a persistent worry – the frequent power outages in the neighborhood. He cannot afford inverters or diesel generators to provide back up power, and sans an alternate, business stops until the lights come back on.

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.

Lalit, on right, with one of his employees at the Chill and Grill.

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 device, targeted at the Bottom of the Pyramid market (a country’s poorest socio-economic group) made famous by the late management guru, C.K.Prahlad, would be particularly useful for rural or semi-urban populations of developing countries like India – and for those like Lalit, who cannot afford to buy high-end power backup options such as inverters or diesel generators. For example, in villages which only get a few hours of power every day, the device could be charged when power is available through a community charging center. It can then be used to run devices during nights when power might not be available, such as lights for children to study. Road-side vendors, who might not have access to power from the grid, could also charge needed devices before leaving home in the morning, and use them at their shops at night.

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.

Battery Pack

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.

The device offers potential business opportunity for companies engaged in rural and semi-urban electrification missions. It doesn’t require much capital investment and is easy to build. It also provides a cleaner and potentially cheaper alternative than burning kerosene lamps, and is also compact, light weight, and portable. Most importantly, the device can power homes and communities at the “bottom of the pyramid” for whom access to reliable power is still a challenge.

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.