Can tomatoes be used to generate electricity?

Estimates are that Australians throw out around 4,000,000 tonnes of food a year. On top of that is the food that never makes it to a consumer’s basket because it passes a use-by date, and then there is the food that doesn’t make it to the retailer because it doesn’t meet standards. The amount of food we waste is staggering and if we want to make moves toward sustainable living then more frugal use of food is a must. Inevitably however there will be some food waste, which is where things like composting make such powerful sense. Imagine, though, if we could find even wider uses for food waste such as, oh I don’t know, using tomatoes to generate electricity?

There is theoretically enough tomato waste generated in Florida to power Florida's Disney World for 90 days.

This opportunity is exactly what has been found by researchers looking for ways to make use of spoiled and damaged tomatoes which, if not composted, will make their way into landfill and produce methane (a greenhouse gas). The researchers created a microbial electrochemical cell that uses bacteria to break down and oxidise organic material.

Experiments showed that bacteria interacting with tomato waste releases electrons that can be captured by the fuel cell and become a source of electricity. The lycopene so richly supplied in tomatoes also proved to be an excellent mediator to encourage the generation of electrical charges from the damaged fruits.

It was also found that tomato waste was actually better than using pure “substrates” to generate electricity. At the moment the output generated by the tomatoes is quite small; 10mg of tomato waste produces 0.3 watts of electricity. However, increasing the scale of the electrochemical cells and further refining the process could improve output. As an example, the researchers say that there is theoretically enough tomato waste generated in Florida to power Florida’s Disney World for 90 days.

Needless to say, the excitement around this is electric.