Royal College of Art graduate Yu-Chang Chou has developed a "return and reuse" packaging system to help online retailers reduce waste (+ movie).

After watching his wife throw out perfectly useable packaging from her online shopping purchases, Yu-Chang Chou was inspired to develop a sustainable alternative, using a similar model to the bottle-return system used in many European countries.

The customer would opt for for the packaging when they make their purchase. Once they receive the product, they simply fold and reseal the Repack bag and post it back to a central address, in exchange for a refund of the deposit they paid when ordering.

Royal Mail – the UK's national postage system – would then collect the bags and resell them through local post offices.

"One of my favourite parts of the Repack system is using postboxes as return spots," Chou told Dezeen.

"Letter volume has decreased significantly and is expected to keep decreasing. Therefore in the future, maybe post boxes will become useless. Using postboxes as the packaging return spots for Repack can give them a new life and function."

The Repack bags are made of two parts - an outer bag and an inner cushioning. The external layer is constructed with durable polyester fabric made from recycled PET bottles, which is screen-printed and sewn together. The cushioning is microcellular polyurethane, often used in protective sportswear. Both materials are durable and recyclable.

The bags are expected to last for 200 cycles, after which Royal Mail would be able to repair or recycle them.

"Repack provides packaging as a service in collaboration with existing postal systems rather than as a one-off product," said the designer.

"Using these durable Repack bags to send parcels not only increases packaging efficiency and saves packaging costs per use, but also significantly reduces the environmental impact of producing new packaging."

"Through return and reuse, Repack makes online shopping more environmental friendly and cost-effective for both the retailer and costumer," he added.

Chou worked on the project while studying on the Innovation Design Engineering course at the Royal College of Art and presented the work at the graduate show, which concluded on Sunday.

Other designs at the exhibition included an inflatable bag to keep electronic devices safe and an umbrella made from just six parts.