Research Project / Biochar Stability

Biochar can contribute to negative greenhouse gas emissions in the form of long-term carbon storage. It is important for the development of the biochar market to strengthen the knowledge around biochar stability in soils over long times and to develop ways of accounting for biochar stability.

This 4-year research project, named Biochar Stability: supporting transparent & reliable carbon removal, is funded by the Swedish Energy Agency. It started in March 2022 and is finishing in December 2025.

Background

Biochar produced from biomass has large potential to provide negative greenhouse gas emissions as a stable carbon sink in soil alongside other climate change mitigation benefits. A hurdle for biochar deployment at scale has been the knowledge about the stability of biochar over longer time periods, also referred to as persistence or durability.

This project aimed at consolidating the knowledge around biochar carbon storage in soils.

Research objectives (as stated in 2022)

  • Knowledge on biochar stability in Swedish agricultural soils
  • Field trials established for long-term evaluation of biochar stability
  • Open database for international research data on biochar stability
  • New models for calculation of biochar stability based on biochar properties and environmental conditions
  • Practical guidelines on how to use the stability models developed

Research outputs (as of 2024-12-06)

Activities on-going and planned

Several activities on-going and new ones are planned in 2025:

  • Laboratory incubations with non-labelled Swedish biochars started in February 2022 have been concluded. Analysis of data is on-going.
  • Laboratory incubations with novel labelled biochar started in September 2023 is on-going. Characterisation and other analyses are on-going.
  • Update of recommendations and review of new research findings is planned for 2025.


*Figure - Incubation equipment, biochar sample, and elemental composition chart*
Figure - Incubation equipment, biochar sample, and elemental composition chart


Timeline and work packages

The project has 5 work packages (WP):

  • WP1: Stakeholders & guidelines
  • WP2: Biochar characterisation
  • WP3: Laboratory incubations
  • WP4: Field trials
  • WP5: Data analysis

The project started in january 2022, and will continue until year 2025:

  • Year 2022: survey & roundtables with stakeholders (WP1) / biochar collection & characterisation (WP2) / experiment design (WP3-4) / litterature data collection, modelling toochain, and first re-analysis (WP5)
  • Year 2023: initial guidelines (WP1-5) / start of incubation (WP3) / start of field trials (WP4) / uncertainty modelling (WP5) / publication of dataset and modelling article (WP5)
  • Year 2024: continued laboratory and field work (WP3-4) / modelling of power and inert pool models (WP5)
  • Year 2025: continued laboratory and field work (WP3-4) / update of recommendations (WP1-5) / publication of other articles (WP2-4)

Project Presentation (dated 2022-06-16)


Contact

For general inquiries: kolinlagringattraknamed@2050.se

*Field trials. Photo: Örjan Berglund*
Field trials. Photo: Örjan Berglund

The team

  • Cecilia Sundberg (SLU, energy and technology) Project leader. cecilia.sundberg@slu.se
  • Elias Azzi (SLU, PhD in biochar systems analysis) Compilation, modelling & analysis of biochar decay data. elias.azzi@slu.se
  • Erik Karltun (SLU, lecturer in soil science at the Soil & Environment Department) Soil and plant interactions with biochar. erik.karltun@slu.se
  • Harald Cederlund (SLU, molecular sciences) Stability characterisation at the laboratory scale. harald.cederlund@slu.se
  • Haichao Li (SLU, Post-doctoral researcher, Soil & Environment Department) Laboratory incubations and field trials. haichao.li@slu.se
  • Helena Söderqvist (2050 Consulting) Knowledge bridge between market & user. helena.soderqvist@2050.se
*Incubation jars. Photo: Harald Cederlund*
Incubation jars. Photo: Harald Cederlund