Life Cycle Assessment of Hemp Cultivation and Use of Hemp-Based Thermal Insulator Materials in Buildings

Abstract

The aim of this research is to assess the sustainability of a natural fiber, such as hemp (Cannabis sativa), and its use as thermal insulator for building applications. The sustainability of hemp was quantified by life cycle assessment (LCA) and particular attention was given to the amount of CO2eq of the whole process, and the indicator greenhouse gas protocol (GGP) was selected to quantify CO2eq emissions. In this study also CO2 uptake of hemp was considered. Two different allocation procedures (i.e., mass and economic) were adopted. Other indicators, such as Cumulative Energy Demand (CED) and EcoIndicator99 H were calculated. The production of 1 ha yielded 15 ton of hemp, whose global warming potential (GWP100) was equal to about -26.01 ton CO2eq: the amount allocated to the technical fiber (20% of the total amount of hemp biomass) was -5.52 ton CO2eq when mass allocation was used, and -5.54 ton CO2eq when economic allocation was applied. The sustainability for building applications was quantified by considering an insulation panel made by hemp fiber (85%) and polyester fiber (15%) in 1 m(2) of wall having a thermal transmittance (U) equal to 0.2 W/m(2)_K. The environmental performances of the hemp-based panel were compared to those of a rockwool-based one.

Energy and environmental assessment of industrial hemp for building applications: A review

“…A considerable number of authors have worked on the assessment of both energy and environmental performances of these products. For instance, Zampori et al [75] performed an LCA of the production (technical fibre and woody core) and use of hemp for the evaluation of the impact generated by the manufacturing of a hemp mat with a thermal conductivity of 0.044 W/m K. The study included assessment of the inventory flows and environmental burdens associated with the cultivation of 1 ha of land and of the sustainability of two walls, where the insulating performances were guaranteed alternatively by hempbased or rock-wool insulating panels. The authors used mass allocation considering that, as also clarified in the previous sections, hemp cultivation delivers the following three co-products: woody core; fibre; and, dust.…”

Multiple Criteria Assessment of Insulating Materials with a Group Decision Framework Incorporating Outranking Preference Model and Characteristic Class Profiles

“…For all materials but hemp fibres, Ecoinvent Database (Ecoinvent 2010) was used as a source of foreground and background data related to both production and assembly processes as well as to the transport, electricity and fuel consumption. Instead, for the hemp processes the underlying data was derived from Zampori et al (2013).…”

Hemp Fiber Reinforced Composites: A Review

“…Stefania Manzi1 et al [6] studied panels, obtained by bonding hemp hurds with different binders, characterized by a reduced environmental impact, exhibited very promising properties, both in the case of the low density panels, intended as composites for building thermal insulation, and high density panels, designed as possible substitutes for formaldehyde-bonded wood particle panels. Balciunas et al [7] and Zampori et al [8] found that in hemp-based composites for the building industry, hemp hurds are generally bonded with Portland cement, slaked lime or organic polymers. Julia Cigasova et al [9] dealt with the use of hemp hurds as organic filler in building material.…”