Chalmers students Viktor Skans and Hanna Steinum have received Landshypotek’s essay award for the future of green industries in 2023. The winning thesis is about biochar from harvest residues and the result has great potential for both agriculture and reduced carbon dioxide emissions.
The thesis was written in the master programme Industrial Ecology at Chalmers, and explores how harvest residues can be taken care of and converted into biochar through pyrolysis. The biochar is then spread on to the fields, which contributes to making them more fertile. This in turn can reduce the need for fertilisers and it also forms a carbon sink that reduces the total carbon dioxide emissions from agriculture.
Viktor and Hanna, why did you choose this topic?
“It is a combination of technology and sustainability, which are topics that interest us both. We saw how large amounts of biomass in the form of crop residues are often not utilised in agriculture today. At the same time, the pyrolysis technology exists and is actually relatively simple and could be used by almost everyone”.
Which are the obstacles, why is this not already available to a greater extent in Swedish agriculture?
"The challenge is to get both the logistics and the economy to work together. It is also difficult to measure the effects because each soil is unique. Even if biochar can have positive effects on the fields at one farm, it is by no means certain that it will have the same effect on another. Furthermore, it is an investment that needs to be recouped for each farm. The optimum would be to find models where a number of farms share a pyrolysis boiler in a certain geographical area”.
What do you hope this will lead to?
"Of course, we want more people to recognise biochar and its potential in agriculture. The dream, of course, is that what we are doing can help farmers become innovative pioneers when it comes to reducing carbon dioxide emissions. There is EU funds to apply for these investments and if the Swedish Board of Agriculture and other authorities are proactive, there are great opportunities to reduce Sweden's emissions. Presumably, someone has to take the lead and show that it actually works, and then more people will dare to invest in it”.
The jury's motivation for the winning essay:
"This is an essay that impressively fulfils Landshypotek's criteria for the award. The authors of the paper have tackled a current and important topic that is highly relevant from a development perspective and affects many stakeholders in society.
In a positive and curious way, the study has described the flow of carbon in agriculture and shown the possibilities of biochar - both how it can improve soil fertility and by quantifying the carbon sink that its use can provide.
The authors have applied their results to an agricultural area and shown positive effects on both fertility and the ability to bind more carbon. In a concrete way, they have been able to show how it is applicable in the green industries."