Mycelium based composites (MBCs) are biocompatible, biodegradable, and compostable materials derived from agricultural, agro-industrial, and forestry residues, adding value to waste materials. They offer ecological benefits by potentially reducing emissions associated with conventional waste management practices. MC production is considered cost- and energy-efficient due to the sourcing of raw materials and minimal manufacturing processes. Previous research and recent pilot projects from Mycohab identified MCs as a solution to environmental and socio-economic challenges in Africa, particularly by repurposing substantial biomass reserves from agricultural waste.
A recent study from Stefania Akromah, Neha Chandarana, Jemma L. Rowlandson and Stephen J. Eichhorn published in Nature.com, assessed the environmental impact of MCBs in the construction sector through a life cycle assessment (LCA), emphasizing the significance of the electrical power source in the culturing and post-processing phases.
The study highlighted the ecological footprint of MCBs, emphasizing the importance of sustainable fuel sources, efficient transport, optimal biomass composition, and water management. The energy mix of countries also plays a crucial role, with higher impacts in fossil fuel-reliant countries (e.g., South Africa) compared to those using more renewable sources (e.g., Democratic Republic of the Congo, DRC).
The study also highlighted the environmental benefits of local production facilities near waste sources and positions MCBs as a more sustainable alternative to traditional materials like concrete. The findings provided insights for developing sustainable practices in MCB production, addressing potential environmental repercussions pre-emptively. Future LCAs should include comprehensive analyses of mechanical properties and socio-economic costs to enhance the sustainability of MCBs in Africa.
Key Recommendations:
Fuel Source:
Electricity used in autoclaves, incubators, and ovens is a major environmental hotspot.
Renewable energy (e.g., solar) can reduce the ecological footprint, but high costs may lead to the use of traditional fuels like firewood and charcoal.
Traditional fuel alternatives can reduce the footprint by 70-80%, but considerations of fuel efficiency and emissions controls are necessary.
Transport:
The environmental impact correlates with travel distance and mode of transport.
Local sourcing is ecologically beneficial.
Efficient transport strategies and compliance with emission standards are crucial, especially in high-emission countries.
Biomass Composition:
Biomass composition significantly influences sustainability; nutrient-rich biomass may have higher environmental impacts.
Future studies should explore the use of expired or slightly deteriorated biomass.
Agricultural waste availability varies by climate and season, potentially impacting consistent MC properties.
Water Consumption:
High water requirements for biomass hydration and sterilization increase the risk of water scarcity.
Water reclamation and treatment systems could mitigate this risk.
Repurposing contaminated water for MC production could present opportunities for sustainability.
Land Use:
Land use impact, although not addressed in this study, can significantly affect environmental sustainability.
Agricultural practices contribute to global GHG emissions and biodiversity loss.
Future studies should consider land use impacts related to biomass sourcing.
Methodology This LCA study, based on ISO 14040 and ISO 14044 standards, aims to identify environmental hotspots of MCB production and compare the life-cycle impact of MCBs to traditional concrete bricks. The study focuses on Ghana and extends to other African countries, considering the energy mix, biomass composition, transport, and water usage. The MCB production model includes biomass sterilization, grain spawn preparation, inoculation, incubation, and drying.
[Image credtis: Mycohab / Scientific Reports (Sci Rep) ISSN 2045-2322]