‘Super Rev’ or Super Reefs, is a Danish project that aims to re-establish 55 square kilometres of reefs off the country’s coast. Behind the work is the international group of artists examining whether it is possible to create a stone reef from newly-developed concrete. The expectation is that the construction industry can use the experience for future coastal protection projects, bridges, tunnels, and offshore wind farms, which function as stone reefs for seaweed and animals. The objective is to help increase marine biodiversity.
“Marine ecosystems have been put under pressure due to climate change, overfishing, reef degradation, and far too many nutrients from agriculture and buildings. Therefore, it is necessary to conduct research into innovative materials that can promote marine biodiversity. In the long term, we hope that the large-scale infrastructure projects of the future will not only be designed to produce green energy and develop sustainable climate protections—but that they will also contribute to strengthening marine life,” says Wolfgang Kunther, who is a materials scientist at DTU Sustain.
The project functions as a home for marine animals, as a scientific experiment, and as a work of art. Crown Prince Frederik of Denmark inaugurated the work in 2021. In the same year, the artists received the Crown Prince Couple’s Cultural Award for using art to put important issues such as sustainability, the lives of other species, and climate challenges on the debate agenda in both Denmark and internationally.
“The work is not just a restoration project—we’re also interested in developing new ways of building in the future with focus on the needs of other species. It’s a huge task which we can’t perform alone—but we can achieve great things through partnerships and collaborations,” says Malene Natascha Ratcliffe, CEO of Superflex.
Concrete not only releases CO2 in the manufacturing process and during heating—it also absorbs CO2. Some call it a sponge effect because the concrete soaks up CO2 just like a sponge. The effect is due to a slow process that occurs when the cement solidifies and reacts with the CO2 present in the atmosphere and in the sea. This creates the same kind of limescale known from, for example, bathroom limescale deposits.
“In the vast majority of concrete structures used for maritime infrastructure projects, concrete is used together with steel reinforcement. But when reinforced concrete is affected by seawater, the reinforcing steel begins to rust—the only question is when this happens. With the type of concrete structure we’re testing, we don’t expect that it’s necessary to use steel. This means that the useful life will be longer than for conventional concrete structures in seawater. This has a great environmental benefit,” says Wolfgang Kunther.
He continues to state: “This is a whole new way of looking at concrete structures. Both in terms of biodiversity and concrete development. We do not cast standard materials. Therefore, we must ensure that the materials last. We need to know what happens if we replace part of our familiar concrete with something new. Especially if we’re talking about large infrastructure projects that should last for 100 years without major repair interventions. In this way, you could say that we’re pioneers.”
