nxsut 3.0

nxsut 3.0 - Global Environmentally-Extended Supply-Use table in physical units

This repository contains the 2023-2025 releases of nxsut 3.0, the supply-use database for environmental impact analysis built by eNextGen and the SESAM research group of Politecnico di Milano on top of EXIOBASE Hybrid v3.3.18 with MARIO.

How it is built

The original EXIOBASE database is updated in terms of electricity supply (from EMBER) and trade mixes (from ENTSO-E) to represent electricity production and trade of 2023-2025. ENTSO-E provides data only for European countries: development releases - for internal use only - of nxsut included other data from other sources to represent electricity trades for non-EU countries. nxsut 3.0, however, relies only on ENTSOE for licensing purposes. Plus, we did not notice significant differences in electricity carbon footprint of non-EU countries even without applying trade corrections.

Electricity commodity is pooled: this means that, although the original database is in Isard format, a fictitious activity - Electricity - supply - is introduced in each region, absorbing all domestic and imported consumption of electricity of its region. Electricity trade is then represented on the supply matrix, with a "Chenery-Moses-like" arrangement, where in each region, all Electricity - supply activities domestically produce or export a fictitious commodity - Electricity - need. A didactic example is described on the MARIO documentation.

The nxsut building pipeline imports also the procedure provided by Ghezzi et al to introduce +20 new activities related to innovative steelmaking technologies, including hydrogen production. Ghezzi et al also introduce a reallocation of blast furnace gases emissions to the iron and steel manufacturing activity, which makes both electricity and steel carbon footprint more aligned to literature ranges in most regions.

Raw inputs are progressively governed in nxbase, the eNextGen data backbone, and reach this pipeline through nxbase's public read-only API.

Rationale

nxsut core use cases are carbon footprinting and modelling: while the original EXIOBASE Hybrid database refer to 2011, we strongly believe using it in 2026 for these specific purposes still makes a lot of sense, thanks to its physical-unit representation of the global economy and to the workflow we put together to align its result to more recent literature, where it matters most. A blogpost on eNextGen's website shows how electricity carbon footprints from nxsut compares with the most authoritative sources in literature. Carbon footprint of steel are aligned to the one showed in Ghezzi et al. Other work is ongoing - see section below - to make these data easily updatable over time and pragmatically useful for these applications.

Contents

MARIO-readable .txt files for 2023-2025 releases. Just parse them as any other MARIO txt table, following this guide. The code used to generate the database is available on GitHub.

Ongoing work

• A paper on embedding photovoltaic supply chain is currently under review and will be hopefully embedded soon
• Updates of supply and trade mixes is under investigation for other commodities

License

Licensed under Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) - see LICENSE. Share and adapt for any purpose, including commercially, with appropriate credit and under the same license (ShareAlike).
nxsut derives from EXIOBASE Hybrid v3.3.18 (CC BY-SA 4.0), so the ShareAlike term is inherited.