Severn Trent generates clean energy with leftover pumpkins

The company asked members of staff to bring in their unwanted pumpkins, which otherwise would have gone to landfill, so they could be fed to an anaerobic digestion plant to create clean energy.

Severn Trent commercial business manager Chris Jellett said: “Millions of people buy pumpkins to decorate their homes for Halloween but many of those are just thrown away after the event.

“By using our anaerobic digestion plant we can make good use of those pumpkins – in fact one 600g pumpkin could power a lightbulb for 24 hours.”

Severn Trent’s anaerobic digestion plant in Coleshill produces 2.4MWh of energy a year.

“Pumpkins, like all food waste, are packed with energy which with a bit of ingenuity can be unlocked and turned into power,” Jellett added.

“The process works in a similar way to us eating food. Trucks full of food waste are emptied in to the machine which removes packaging and then chews it up and digests it, much like a human body.

“The anaerobic digestion ‘tummies’ process different types of food waste. As that happens, methane gas is produced and collected on the top of the tank, without being released into the air. It’s then sent over to a machine called a combined heat and power unit (CHP), which turns it into green energy to power the works.

“Any leftover material can be used as fertiliser on local fields. The whole digestion process takes around 90 days from the plant to field. And, the best thing is that this carries on 24/7, 365 days a year.”