A recent woodlands blog discussed the millions of Christmas trees that end up as landfill material. This is also true for a material that is generated in cafes and restaurants across the U.K - the ‘waste material’ is coffee grounds. Coffee is the second largest traded commodity after petroleum. One estimate suggests that six million tonnes of spent coffee grounds go to landfill every year. Landfill sites account for a fifth of the UK’s methane emissions; methane is an extremely potent greenhouse gas associated with global warming & climate change.
Some cafes and restaurants offer their coffee grounds to customers - who want to use it in their gardens / compost heaps. However, ‘fresh grounds’ are still high in various chemicals e.g. caffeine, tannins and chlorogenic acid. This material needs to be ‘detoxified’ before it can be used in the garden - this can be done by composting the material (for approximately one hundred days).
Alternatively, this coffee waste can be used or processed to create
- high value chemicals (e.g. chlorogenic acid has been investigated for its possible anti-inflammatory / anti-oxidant effects) or
- an energy source or
- soil conditioner / fertiliser / mulch
Whilst certain recycling / processing initiatives are in their early stages, some having ‘taken off’. For example, the bio-bean initiative. Bio-bean is in the ‘clean energy’ business. They collect waste coffee grounds and use them to create a biofuel - particularly for wood burning stoves . Each tonne of coffee waste can create 5700 kilowatt hours of energy !
By processing some 50,000 tonnes of coffee waste each year, they create COFFEE LOGS. A Coffee Log is made from the grounds of circa 25 cups of coffee; a log burns hotter and longer than kiln-dried wood. According to bio-bean, this recycling of coffee waste results in 80% less emissions than landfill. Coffee Logs can be used for woodburners, stoves and open fires, The company also makes coffee-derived biomass pellets, which are designed for industrial use - and a bio-diesel.
On a more local scale, there are a number of ways of using coffee grounds in a productive way - from repelling insects to tenderising meat, visit.healthline.com/nutrition/uses-for-coffee-grounds for further details.
Thanks to Pexels on Pixabay for featured image