Hemp can store CO2 as efficiently as wood in raw materials for the construction industry, and should meet EU certification criteria for carbon credits, a new report from Germany suggests.
The report found that carbon removal through hemp is in a range similar to that for fast-growing spruce, Douglas fir and birch trees – both on a gross and net basis.
Based on existing scientific literature, the report was compiled by nova-Institute, a research organization based in Hürth.
“For hemp, the amount of carbon stored in the raw materials which can potentially be used in the construction and insulation industry is found between 9.5 and 11.4 t CO2eq/ha (gross), with the main sensitivity being the straw yield per hectare,” the report notes. “Higher straw yields result in more stored carbon per hectare, whereas the opposite holds for lower yields.”
Gross refers to total carbon captured by hemp in the field. Net figures for hemp subtract any greenhouse gases generated from planting, harvesting, decortication and transporting hurd, fiber and dust, while for wood it takes into account emissions resulting from debarking and transport to the next processing facility.
According to the paper, net carbon removal rates range from 5.5 to 11 tons per hectare for both hemp and wood.
The European Commission’s Directorate-General for Agriculture and Rural Development (DG AGRI) is aware of the potential environmental benefits of hemp, which is “an interesting option” under the EU’s proposed carbon removal certificate framework, according to the report. That framework recognizes carbon benefits derived from nature-based solutions, such as restoring forests, soils, and innovative farming practices; long-lasting products and materials; and technology such as bioenergy with carbon capture and storage, or direct air carbon capture and storage.
“The aim of the EU carbon removal certification framework is to scale up carbon removal activities and fight greenwashing by empowering business to show their action in this field,” according to the nova-Institute report. “The proposal sets out a voluntary EU-wide framework to certify carbon removals generated in Europe. It sets out criteria to define high-quality carbon removals and the process to monitor, report and verify the authenticity of these removals. To receive certification, the carbon removals will need to be correctly quantified, deliver additional climate benefits, strive to store carbon for a long time, prevent carbon leaks, and contribute to sustainability.”
EU plan and goals
The circular economy action plan of the EU aims to cut the carbon footprint of buildings through “circular renovation” initiatives that promote green infrastructure and the use of organic building materials that can store carbon.
A total of 939 million tons of greenhouse gas were emitted by European states in the fourth quarter of 2022, a 4% decrease compared to Q4 2021, when 978 million tons were released, according to Eurostat. The construction industry contributes an estimated 5 to 12% of member state CO2 emissions.
The EU has a goal of reaching climate neutrality by 2050.