- General information
NameHelsinki Biochar Project
ThemeClimate adaptation, carbon sequestration, circular economy
CommissionAalto University, City of Helsinki
ColleaguesTuuli Markkanen, Mikko Jalas
The Helsinki Biochar Project set up an experimental local to produce biochar from green waste generated in the city and apply it back into it’s green infrastructure. In this way carbon is sequestered into the soil and increase soil resiliency. Which is a potential climate adaptation tool to create more resilient urban green. During years 2022-23, different kinds of organic waste materials are being tested as potential feedstocks for manufacturing local biochar. The project is set out to spread awareness about the benefits of, and providing practical know-how of using biochar among the city administration and citizens.
What is biochar?
Biochar is a char like material with a high carbon content. It can be added as a soil amendment changing the absorption capacity and structure of the soil. By doing is, biochar is both a means to sequester carbon and has potential to play a role in climate adaptation strategies. Increasing the capacity of urban soils to be more resilient to extreme weather events, such as storms and prolonged periods of drought, could potentially serve as one of multiple means for urban climate adaptation.
Experimental biochar sites in Helsinki
In collaboration with HSY (Helsinki’s waste processing service) and KYMP (the environmental division of the City of Helsinki) various sites were biochar experiments took place. These included: a football field, tram track, urban meadows, soil replacement around existing trees, and perennial plantings.
Because biochar is still a relatively unknown material, the Helsinki Biochar Project aims to increase the awareness of citizens on the potential of biochar. In order to do so, the project strives to set up a series of trials in the Helsinki metropolitan area to demonstrate the various stages of the biochar cycle to citizens, ranging from showcasing the production of biochar from local waste streams, how it works as a means to sequester carbon and finding engaging ways to utilise the material as a climate adaptation tool. The goal of the Helsinki Biochar Project is to demonstrate that converting local waste streams into responses to climate change is not just a distant process for decision makers only, but can be an engaging capability-building activity for citizens as well. During the course of the project we worked with 4 different gardener groups in Helsinki. Biochar experiments were set up during a series of community work days (talkoots), information evenings and a tour to facilitate knowledge exchange between professionals and citizens.
To promote the project in an engaging way amongst citizens and other stakeholders, a small-scale exhibition module was developed. These modules contain conceptual representations of some of the biochar experiments conducted in Helsinki, visualizations of the concept of the project, the potential of biochar in urban environments, the utility of biochar in soils, and samples of the feedstocks. In addition, the exhibition modules can be complimented with the distribution of biochar in the 3L bags containing woodchip biochar from one of the experimental feedstocks; 3 large posters (90x135cm); and an instruction manual on how to use biochar at home. All communication materials are designed according to the visual branding guidelines of the City of Helsinki.