Algae curtains sequester as much CO2 as 20 large trees – every day

A group in the UK has designed algae curtains that could act as a carbon credit for architecture.

Shelter is a basic human need, but certain buildings are burning the planet. The cement we use to construct buildings around the world accounts for up to 8% of heat-trapping carbon dioxide emissions, according to a recent Chatham House report. And we’re unlikely to stop using it any time soon. That’s because cement is the second most widely utilised natural resource on earth after water.

Enter algae curtains.

Alage Walls

Designed by Photo.Synth.Etica, a collaborative group from the UK made up of ecoLogicStudio, UCL’s Urban Morphgenesis Lab and the University of Innsbruck’s Synthetic Landscapes Lab, the curtains are made with a bioplastic filled with a serpentine line of algae. AlgaeClad, which is comprised of modules of ETFE, comes with an aluminium frame. The designers told My Good Planet the curtains will last for up to five years, while the more rigid AlgaeClad would last up to 30 years.

So how does it work?

As air meanders up through the cladding, algae microbes gobble up the pollution, converting it into biomass that can then be used to make more bioplastic. The system also releases oxygen, a bonus for air quality. Algae curtains and cladding can capture and store up to one kilogram of carbon dioxide per day, according to ecoLogicStudio. That’s roughly the same level of carbon sequestration performed by 20 large trees.

Algae Walls a

If we can’t quit cement (which should be the end goal given the numerous, cleaner building materials being developed on a daily basis), at the very least these can be added to either new or existing buildings to offset their carbon footprint — like a carbon credit for construction and architecture.

Algae curtains made their first debut last year in Dublin, at the Climate Innovation Summit 2018. Photo.Synth.Etica draped 16 2 x 7 metre modules over the first and second floor of the main façade of the Printworks building at Dublin Castle to demonstrate how it works. Honestly, the prototype won’t earn any major beauty awards, but does serve as an excellent example of what we can do when we turn to science and design to answer some of our most critical climate challenges.

In the Anthropocene age, a non anthropocentric mode of reasoning and deploying cutting-edge technologies based on digital and biological intelligence could be at the core of urban design and stimulate our collective sensibility…,”  Photo.Synth.Etica notes in a press release. “Smart cities, smart homes, autonomous vehicles, robotic factories, etc. dominate the current panorama of popular futuristic scenarios,” the group adds “but they all desperately need spatial and architectural re-framing to engender beneficial societal transitions.” And it turns out, they’re not alone in seeing the benefits of algae.

In an article published in the journal Earth’s Future, researchers note that while bioenergy carbon capture and storage (BECCS) could help reduce atmosphere CO2 concentrations, doing so competes for arable land and freshwater. Not so with algae. “The synergistic integration of algae production, which does not require arable land or freshwater, with BECCS (called “ABECCS”) can reduce CO2 emissions without competing with agriculture,” the researchers note. Algae offers other services too.

Researchers at the IKEA-backed experimental lab SPACE 10 have demonstrated how algae can be used to combat malnutrition, help end deforestation by replacing soy protein in livestock and poultry feed and clean industrial wastewater — among other things. SPACE 10 made a big splash internationally in 2017 with their four-foot tall Algae Dome, a giant food-producing bioreactor they displayed right outside their living laboratory in Copenhagen, Denmark. Combined, these projects elevate algae’s profile from mere microbe to a life-changing tool in the fight against climate change, food insecurity and pollution. But there’s still a way to go.

Algae Wall My Good Planet

As they continue to work with their partners to refine their algae offerings, which would cost anywhere from 300 euro per square meter to 2000 euro, depending on the “morphological complexity of the system and material employed,” ecoLogicStudio’s Marco Poletto says they have received significant interest from both the private and public sector.

The main motives for private companies are branding, corporate sustainability and improved building performance,” he says. “Public entities are interested in promoting our innovation to help them meet their policy targets and SDGs. Also we are in the process of raising capital to scale up our operations and are looking for hi-end manufacturing partners.” And they’re working on a variety of other futuristic projects too.

These include a photosynthetic sculpture for the Centre Pompidou in Paris, a research project that substitutes the use of water with biogel as the algae medium, and 3D printing techniques to prototype architectural photobioreactors. In all cases, the group’s goal is to reduce, as much as possible, the environmental impact of human beings on urban environments. Which we think is a worthy goal.

Photography: ©NAARO
Tafline Laylin
Tafline Laylin

Tafline Laylin is a freelance editor and journalist best known for her coverage of “green design” and environmental issues in the Middle East. Based in Washington State, she is currently researching truly restorative design solutions to the planet’s mounting ecological challenges.