ThinKing November 2022: Cooling trees on façades improve the urban climate

08.11.2022

The GraviPlant – a smart planter elevates green façades to the next level, literally! It makes it possible to plant façades with small trees one level above the regular green façade.

A lightweight technology award for green façades? No, that would be too simple. The GraviPlant – a smart planter elevates green façades to the next level, literally! It makes it possible to plant façades with small trees one level above the regular green façade. A variety of lightweight technology ideas keep the weight of the tree planter itself low. In addition, the idea for trees growing horizontally on façades with automated gardening care generates a multi-layer lightweight technology system for the urban space, while cooling and protecting the building and improving the city climate. Because of this, the ThinKing for November 2022 is being awarded to Visioverdis 2.0 GmbH for the GraviPlant.

The State Agency for Lightweight Technology Baden-Württemberg is pleased to present this innovation with its ThinKing Award for the month of November 2022. Every month, Leichtbau BW GmbH promotes innovative lightweight technology products and services in Baden-Württemberg under this label.

At a glance:

• Reducing the CO₂ footprint: Greening urban façades improves the service life of the building, saves CO2 and produces oxygen.
• Energy-saving: Energy costs for the building’s air conditioning can be cut in half.
• Tapping into lightweight technology potential: Heat insulation and sound protection using greening supports resource-saving building methods.

The first time you see the GraviPlant, you may be tempted to turn your head 90 degrees – after all, plants growing horizontally are not normally a part of our reality. Tree-like bushes grow from these planters not vertically, but rather at a right angle to the façade to a depth/height of approximately two meters.

“The GraviPlant is a combination of plant and technology. The bush is turned slowly on its anchor so that experiences gravity on all sides and grows horizontally – its growth is also decelerated”, says Dr. Alina Schick, strategic management and product planning consultant for Visioverdis 2.0 GmbH, explaining how the plants grow horizontally.

Façade cooling and sound protection save energy and materials

The GraviPlant brings ecology and technology to urban spaces: better thermal and sound insulation for façades, which can thus be constructed with more efficient use of materials and in line with lightweight building principles. Compared to unshaded buildings, green buildings cut energy costs almost in half per year and square meter thanks to evaporation cooling¹. Marco Schmidt, Technical University of Berlin, Institute of Architecture, Section Building Technology and Design prove this through years of research. The biggest contributor to these savings is lower energy consumption for building cooling during the summer. 

Climate protection and improved climate

However, a green façade does more than just act as a heat shield. In addition, the plantings provide building materials a self-regenerating protective cover that guards them against weather, air pollution, and UV radiation. This extends the service life of the building envelope, reducing its CO2 footprint. In addition, the plants filter pollutants out of the air and water and produce oxygen for improved air quality. CO2, in contrast, is bound up in the biomass and removed from the environment. Fine dust is also bound up and removed via rain water.

Combined with near-wall greening systems, it is even possible to cover a façade in multiple green layers, since sunlight can penetrate through the horizontal growth to the near-façade greening. Ecological diversity, and the presence of an ecosystem of bushes, trees, and plants of different heights improve both the system's cooling effect and its impact on human well-being.

A smart planter design

The GraviPlant itself supplies the plant with the ideal levels of water and nutrients through a specified, automated, and digitally controlled process. The planter, designed as a pot-in-pot system, supplies and turns the stem of the bush. The inner pot – which holds the plant – contains the substrate, sensors, and roots. It is attached to a static unit, which is fastened in the façade and covered. It contains the motor, water tank, gears, hollow axle, and electronic components, for instance. Insulated openings are provided in the façade where the GraviPlant is installed and supplied with water and electricity. A technical and plant health check is conducted twice a year.

Further lightweight technology potential

From first draft to the current stage of development, Visioverdis 2.0 GmbH has already been able to reduce the weight of the GraviPlant filled with substrate from 160 kilograms to less than 100 kilograms. The empty weight is currently around 37 kilograms. The company has achieved this reduction primarily through an improved layout, which allowed the size of the system to be reduced. The technical components for the current version of the GraviPlant take up a space of 42 x 42 centimetres, and are 60 centimetres long. “Currently we are using stainless steel, but we are looking for a more sustainable, rigid, and lightweight material that is also resilient enough to make the GraviPlant even lighter” says Dr. Alina Schick. “The next step in development will also be to find lighter non-organic substances for the substrate, since this makes up a large percentage of the weight”.

About Visioverdis 2.0 GmbH

Visioverdis 2.0 GmbH develops green tech products for the urban environment. The company combines the potential of plants and technology to create innovative and forward-thinking solutions. By doing so, this start-up from Baden-Württemberg supports municipalities, project planners and builders in making cities greener, offering them new options to implement climate adaptation strategies and plan building projects that fulfil urban sustainability objectives.