Furniture made of recycled plastic and fabrics made from plastic bags are among winners of the Ro Plastic Prize competition.

German designer Alexander Schul won the design category of the contest set up by Milanese gallerist Rossana Orlandi, which challenged designers to develop new ways of recycling and reusing plastic.

His Substantial furniture collection – comprising a chair, a lamp and a side table – is made entirely from recycled plastic.

Schul created the pieces using sheets of high-impact polystyrene. The designs are intended to be universal, practical and easily manufacturable on a large scale, using efficient production methods.

"Considering the fact that only around 40 per cent of the plastic in Europe gets recycled, this design offers an opportunity to raise that percentage," said Schul. "Part of the problem could thus be transformed into added value."

Hend Riad and Mariam Hazem from Reform Studio won the home textiles category for their Plastex project – a line of colourful textiles made of reused plastic bags.

By incorporating this material into everyday products such as stools and chairs, the studio hopes to realign the perception of plastic bags, not as trash, but rather as a valuable resource.

Precious Plastic, an initiative led by Dutch designer Dave Hakkens, topped the conscious innovation projects category.

In addition to designing a series of machines made for recycling plastic, Precious Plastic has also produced a series of open-source video tutorials showing viewers how to make the machines themselves.

Designed using basic materials, tools, and universal parts, the machines can be built all over the world by anyone. They include a shredder machine, an extrusion machine, an injection machine and a compression machine.

Dezeen is media partner for the Ro Plastic Prize. It forms part of Orlandi's Guiltless Plastic initiative, a project aimed at changing the perception of plastic and ensuring the material is used responsibly.

Winners of the competition were chosen by an international jury, which included Dezeen founder and editor-in-chief Marcus Fairs, trend forecaster Li Edelkoort and Google's head of hardware design Ivy Ross.

They were announced during a ceremony in Milan last night, at the Museo Scienza e Tecnologia Leonardo da Vinci di Milano, coninciding with Milan design week.

Each winner received a prize of €10,000.

Orlandi praised Schul's project, which she believes could help raise awareness and encourage change.

"I hope to succeed with this project in further stimulating the sensitivity of individuals to such a serious topic, spurring them to change their lifestyle: avoiding the abuse of plastic and its incorrect disposal before it contaminates both sea and land," she said.

The competition attracted over 300 entries submitted from across the globe, submitted by an array of applicants, from children and universities, to cooperatives and design studios.

No prize was awarded in the packaging solutions category, as judges felt the submissions failed to meet requirements. However a new contest will be launched for this category by outlet operation firm Value Retail, in partnership with the Bicester Village Shopping Collection.