Open Access

The environmental performance of insulation materials for liquid hydrogen storage tank application is important to the development of sustainable supply chains. As new materials keep evolving, there is a need to assess their environmental impact. Therefore, this study investigates the environmental sustainability and circularity of cryogenic insulation concepts, namely vacuum insulation panels (VIPs), exclusively focussing on their core materials. Employing a cradle-to-grave life cycle assessment model, the VIP core materials are investigated with a special focus on glass bubbles. Based on the results, the global warming potential of the considered core materials, namely, glass bubbles, silica aerogel, fumed silica, expanded perlite, glass fibre, and polyurethane foam is 9.21∗10^−2, 7.00, 2.50∗10^−1, 3.63∗10^−2, 6.68∗10^−2, and 1.88 kg CO2 eq. per functional unit, respectively. In general, silica aerogel and polyurethane foam are the least environmentally friendly materials, while the most sustainable is expanded perlite, followed by glass fibre, glass bubbles, and fumed silica.

Developing a sustainable hydrogen supply chain is important in facilitating the energy transition towards climate neutrality. Hydrogen in its free form can be stored and transported either as a gas or a liquid. Due to gaseous hydrogen's comparatively low energy density, liquefied hydrogen (LH 2) is often preferred, especially with regard to long-distance transportation and storage in bulk. A notable challenge associated with LH2 is the inherent requirement to preserve it at a low temperature of -253°C. Consequently, the utilisation of thermally insulated tanks is necessary to minimise LH 2 evaporation. There is a lack of literature on the environmental impacts of insulation materials and concepts for cryogenic storage tank applications in the hydrogen supply chain. Hence, this study investigates a novel concept, namely vacuum insulation panels (VIPs), focusing on their core materials, with a view to assessing their environmental sustainability and circularity. A cradle-to-grave life cycle assessment (LCA) model is employed to investigate six distinct VIP core materials, namely, silica aerogel, rigid polyurethane foam, expanded perlite, glass fibre, fumed silica, and glass bubbles (hollow glass microspheres), with a special focus on the latter. The LCA results show that polyurethane foam and silica aerogel rank low in environmental performance, making them less suitable as primary choice. Expanded perlite is the most environmentally friendly material option, followed by glass fibre, glass bubbles, and fumed silica. Improvements to the environmental impact of glass bubbles can be achieved via the implementation of closed-loop recycling in their life cycle.

The NICOLHy project aims to develop a novel insulation concept based on Vacuum Insulation Panels (VIP) that enables the safe, cost- and energy efficient storage of large quantities of LH2. Such large scale LH2 storage technology is necessary for establishing a hydrogen economy with dimensions between 40.000 m³ and more than 200.000 m³ of LH2. However, new design concepts are needed because the currently available technologies used in small and medium storages today are not suitable for up-scaling. The main problems prohibiting the up-scaling are the long production time due to the process chain, the low failure tolerance and the spherical shape, which reduces the payload in technical applications by up to 50% compared to other shapes. The novel concept will change these conditions by a system which is modular, open-form, time-and cost efficient while production, operation and service, multi-failure tolerant and applicable for onshore and offshore applications. The presentations shows details to the concept and presents several safety concerns the project has to deal with. This document contains all presentations from NICOLHys second Stakeholder Meeting.