Food Waste Can now be Used to Power Mobile Phones


Scientists have come up with a device that can digest food waste to produce electrical and heat energy.

A team of researchers from National University of Singapore (NUS) have developed a self-sustaining anaerobic biodigester, which can produce heat and electricity by using food waste as fuel.

Power generated by biodigester

The setup can generate about 200 kilowatt-hours to 400 kilowatt-hours from a single tonne of food waste. The amount of energy generated depends on the composition of food waste. Food with the higher concentration of carbohydrates, proteins and fats generates more biogas; hence, more electrical energy.

Another feature of the system is that it is able to transform about 80 per cent of the food waste fed into it into nutrient-rich digestate, which can be processed to become liquid fertilisers for agricultural and horticultural purposes.

To ensure optimal performance and safety, all the process in the system are monitored and can be controlled. There are sensors that are programmed to send out end-of-process updates and flag any safety concerns in real-time directly to the team via mobile phone alerts. The system even has sensors to trace moisture and gases like hydrogen sulphide.

Setup of biodigester

A mobile anaerobic biodigester is in a 20-foot container and has been placed at Raffles Hall. It aims to treat up to 200kg of food waste daily. The unit takes up two car lots and can be shifted to sites where food waste recycling is required.

It has four batteries that can store the excess electrical energy. These batteries are placed in a mobile phone and tablet charging station situated at the Raffles Hall canteen for complimentary use by students. Researchers claimed that assuming typical usage, the four batteries are able to last about three days. They are now planning to make another unit that can handle a larger volume of food waste — up to 400kg.