What was our motivation?
Lindeborg’s farm got its pyrolysis reactor back in fall 2017. It is one of the first farms in Sweden equipped with a such a reactor to provide heating to its premises and produce biochar. Our case study was performed in 2018-2019, at a time when little data from the plant were available and some operational challenges were reported, in particular during warm winter days. Therefore, the research focused on combining LCA to simulations of the operation of small-scale reactors at the farm level.
Azzi ES, Karltun E, Sundberg C (2021) Small-scale biochar production on Swedish farms: A model for estimating potential, variability, and environmental performance. Journal of Cleaner Production 280:124873. DOI: 10.1016/j.jclepro.2020.124873
The work was presented at a conference and several workshops. Download presentation slides below:
The modelling was performed in python, using brightway2 and ficus. The files are available on GitHub at P2_farm_biochar.
Watch a presentation of the article.
Several small-scale pyrolysis plants have been installed on Swedish farms and uptake is increasing in the Nordic countries. Pyrolysis plants convert biomass to biochar for agricultural applications and syngas for heating applications. These projects are driven by ambitions of achieving carbon dioxide removal, reducing environmental impacts, and improving farm finances and resilience.
Before policy support for on-farm pyrolysis projects is implemented, a comprehensive environmental evaluation of these systems is needed. Here, a model was developed to jointly: (i) simulate operation of on-farm energy systems equipped with pyrolysis units; (ii) estimate biochar production potential and its variability under different energy demand situations and designs; and (iii) calculate life cycle environmental impacts. The model was applied to a case study farm in Sweden.
The farm’s heating system achieved net carbon dioxide removal through biochar carbon sequestration, but increased its impact in several other environmental categories, mainly due to increased biomass throughput. Proper dimensioning of heatconstrained systems is key to ensure optimal biochar production, as biochar production potential of the case farm was reduced under expected climate change in Sweden.
To improve the environmental footprint of future biochar systems, it is crucial that expected co-benefits from biochar use in agriculture are realised. The model developed here is available for application to other cases.
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