Finnish start-up Rens Original developed waterproof and odour-resistant slip-on shoes made of recycled coffee.

Every day, 2 billion cups of coffee are consumed worldwide, the coffee grounds of which contribute to the production of methane, a major contributor to climate change. In addition, 3 million plastic bottles are bought every minute.

The idea for Rens shoes was born out the desire to make shoes that are both sustainable and look good. Each pair of shoes is made of 300g of locally sourced and recycled coffee grounds. The coffee is dried, pulverised and blended with recycled post-consumer plastic (the equivalent of 6 500 ml (20 oz) bottles per pair of shoes) to create a flexible yarn, which is odour-proof, anti-bacterial, quick-drying, and UV light blocking. The yarn is then knitted into a 4-way stretch upper of the shoe.

Despite being knitted, the shoes have been made completely waterproof with what the company calls AquaScreen Tech membrane, rather than using a coating or treatment. The technology allows air to pass through, but protects against water penetration. Rens claims the shoes are as watertight as rubber boots, but while being breathable.

And what about water coming from the inside? The coffee yarn is moisture wicking and fast-drying. Your foot sweat is absorbed int the material and released through the fibres, out of your shoe. Plus, the coffee is odour-proof, so no stinky feet.

The lightweight shoes are available in a range of colours. They are on Kickstarter for a few more hours, where the company has already made over 2,700 per cent the goal.

Photos: Rens Original