Deliverable D6.6 - Integrated sustainability assessment report

ēQATOR project reports

Authors: Sonja Haertlé, Hanna Karg, Guido Reinhardt, Heiko Keller, Nils Rettenmaier

The ēQATOR project is developing electrically-heated catalytic reactors for the transformation of biogas (a mixture of methane and carbon dioxide) to synthesis gas (a mixture of carbon monoxide and hydrogen). Synthesis gas, or ‘syngas’ is a common chemical building block for a variety of products, including methanol.
Renewable methanol is considered an important fuel for hard-to-abate transport sectors and a key platform chemical for the defossilisation of products and services. The ēQATOR concept enables the production of renewable methanol from biogas derived from biomass residues and biogenic waste. Biogas is converted into syngas via catalytic reforming, followed by the actual methanol synthesis in a second step. To utilise as much of the biogenic carbon contained in the biogas as possible, ēQATOR has developed concepts for the electric heating of this energy-intensive process and for the integration of hydrogen produced using renewable electricity.

As part of the project, an integrated life cycle sustainability assessment was conducted to support informed decision-making for both technology development and policy frameworks. The aim of this study was to evaluate the potential sustainability benefits of renewable methanol produced using the ēQATOR concepts, compared with methanol derived from natural gas and to compare different ēQATOR variants using various heating and reforming concepts, as well as different biogas substrates. Another important goal of the study was to identify optimisation potentials to determine focal areas for the further development of the ēQATOR concept. The study joined three separate, complementary assessments of the classic pillars of sustainability – (techno-)economic, environmental and social – into an overall picture and analysed them collectively to provide an integrated view of the sustainability implications associated with the ēQATOR concept. The results are considered in the context of the United Nations Sustainable Development Goals (UN SDGs).

In all analyses, a common set of scenarios was evaluated, based on mass and energy balances derived from detailed process models, representing potential future variants of electrically heated methanol production from biogas and renewable electricity on a scale of 500 Nm3 biogas input per hour. The scenarios encompass two different heating concepts (resistive heating and microwave heating), two different reforming concepts (dry reforming and mixed reforming), two different biogas substrates (manure and the organic fraction of municipal solid waste), as well as two implementation scenarios (either the substrate was used for energy production prior to the installation of an ēQATOR plant, or it was spread on fields or composted).

The main result obtained from the comparison of the ēQATOR systems with conventional or even improved future fossil methanol production is that methanol based on biogas and renewable electricity is associated with a significantly lower carbon footprint. Other environmental impacts and social risks are comparable for both systems. While the ēQATOR concept offers greater raw material sovereignty, it cannot compete with fossil methanol under the current regulatory framework due to raw material prices and economies of scale. It is very likely or likely that an implementation of an ēQATOR system would positively contribute to reaching UN SDGs 3, 9 and 12-15.