Restoring kelp, eliminating single use plastic

KelpDid anyone see the coverage of the Earthshot awards presented by the Prince of Wales in Boston earlier this month? They were awards given to organisations, companies or cities recognised as making a significant contribution to dealing with climate change, reviving our oceans, and other similar objectives. You can watch the whole ceremony on BBC iPlayer Earthshot Prize.

The winner in the Building a Waste-Free World category was a London based company founded in 2014 called Notpla (i.e. not plastic!) They have come up with a unique product made from seaweed – or kelp (to use the more scientific term employed by Sussex Wildlife Trust and local universities involved in the Sussex Kelp Restoration Project).

For those of us able to get to the recent Horsham Green Film Festival, the properties of kelp were explored in several short films. One of the brown algae, it has an extraordinary capacity, not only to grow at the rate of up to 30 cm a day but also to draw in millions of tonnes of carbon per year. Its carbon capture is more effective that that of trees – and the communities of such seaweed around our shores  are rightly known by their traditional name ‘kelp forests’.

Sadly they have been greatly depleted by in-shore trawling over recent decades and surveys demonstrated a severe reduction of kelp communities.  However in 2021, a Near-Shore Trawling By-Law banned this practice. And the results just a year later have been spectacular. The film Sussex Kelp Restoration Project shows how researchers from Sussex and Portsmouth Universities have observed kelp forests regrowing and starting to flourish in a number of areas off the Sussex coast.

OK, you will say, what has this got to do with building a waste free world? The answer lies in the technology pioneered by the Earthshot winner Notpla in which seaweed is turned into an organic, biodegradable substitute for single use plastic, a thin film employed in takeaway food packaging and to make consumable liquid sachets, such as those containing Lucozade given out in this year’s London Marathon!

In addition to this, kelp revives our oceans by helping to restore biodiversity (decapods like crabs and lobsters thrive in a kelp-rich sea), filters the sediment that have been dumped by harbour dredging and oxygenates the seawater. And it’s all happening along our own Sussex coast  – and in a few other kelp-rich locations around the world e.g. the Queensland Indigenous Women’s Project which was nominated in the ‘Revive our Oceans’ category of the Earthshot awards.


by Nigel Phillips