Open source software is software whose source code is publicly available to be examined, modified, and distributed. It's not just a technical matter: it's a collaborative development model that has produced some of the world's most important technological infrastructure (Linux, Apache, MySQL, Python, R, Firefox, Kubernetes). For sustainability, open source plays a fundamental role: it lowers the barrier to accessing tools for sustainable analysis and action, enables global collaboration on common problems, reduces dependence on commercial vendors, and maintains transparency in the methods used for environmental measurement and governance.

Open source tools for calculating emissions

OpenLCA (openLCA.org): the most widely used open source platform globally for life cycle assessment (LCA). Used by universities, NGOs, government agencies, and companies to calculate the environmental footprint of products and services. Includes databases of material flows and emissions. Free and cross-platform. CALIOPE: an open source air quality model developed by the Barcelona Supercomputing Center. Used for air quality forecasts in European cities. GHG Protocol tools: the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD) freely maintain a series of Excel tools and software for calculating greenhouse gas emissions according to the GHG Protocol Standard (the most widely used international standard for corporate emissions reporting). Electricity Maps (electricitymaps.com): a real-time open source map of the carbon intensity of the electrical grid in over 60 countries. Available as an API for developers. Used by cloud companies and consumers to optimize energy loads during hours of lower grid carbon intensity.

Open source software for managing renewable energy

OpenEMS (openems.io): an open source platform for Energy Management Systems (EMS) of buildings and local networks with renewables. Used in Community Energy Systems (CER) to manage energy distribution between local producers and consumers. Home Assistant (home-assistant.io): the most widely used open source platform for smart homes. Integrates thousands of IoT devices and can automatically manage household energy loads based on photovoltaic production. Installable on Raspberry Pi or dedicated servers. Free. pvlib (pvlib.io): an open source Python library for modeling photovoltaic production. Used by researchers, designers, and engineers to forecast the output of photovoltaic systems. OpenDSS (sourceforge.net/projects/electricdss): an open source electrical grid simulator developed by EPRI (Electric Power Research Institute). Used by utilities and researchers to simulate the integration of renewable energy into distribution networks.

Open source software for environmental monitoring

QGIS (qgis.org): the most widely used open source GIS (Geographic Information System) in the world. Essential for visualizing and analyzing environmental geographic data (species distribution, deforestation, water quality, air quality). Open source alternative to ArcGIS (commercial). R (r-project.org): the open source statistical language used by the vast majority of environmental research for analyzing climate and environmental data. Thousands of specialized packages for climatology, ecology, and environmental modeling. Global Biodiversity Information Facility API (gbif.org): an open database with over 2 billion observations of biological species from around the world. Open API for developers. iNaturalist (inaturalist.org): an open source platform for biological citizen science. Millions of users worldwide photograph and identify wildlife species, contributing to a global scientific database on biodiversity. Available as an app.

How to contribute to open source software for sustainability

Contributing to open source for sustainability doesn't necessarily require being a programmer. Ways to contribute: if you're a programmer: contribute code on GitHub (search for "climate change" or "sustainability" in GitHub Explore to find active projects looking for contributors), translation: many open source software projects seek Italian translators, documentation: write guides, tutorials, and FAQs to make software accessible to more users, bug reporting: report issues and anomalies on GitHub, testing: test new versions and provide feedback, donations: many open source sustainability projects are run by volunteers who accept donations through Open Collective or Liberapay. Organizations that coordinate open source climate development: Open Climate Fix (openclimatefix.org, UK), The Green Web Foundation (thegreenwebfoundation.org), ClimateAction.tech (community of tech workers for climate).

The benefits of open source for climate transparency

Methodological transparency is fundamental to the credibility of climate reporting. When a company claims to be "carbon neutral," how do you verify that the calculation is correct? If the tool used for the calculation is open source, any researcher or NGO can verify the methodology, identify errors or manipulations, and reproduce the results independently. This is not possible with proprietary software (black boxes) whose algorithms are not public. For this reason, many ESG (Environmental, Social, Governance) reporting standardization initiatives are pushing toward the use of open source tools or at least toward the publication of calculation methodologies. The U.S. SEC (Securities and Exchange Commission) and the European EFRAG (European Financial Reporting Advisory Group) in their climate reporting frameworks require that methodologies be verifiable.

Open data and sustainability: the most important datasets

Beyond software, open datasets (open data) are fundamental for climate research and action. The most important ones: Copernicus Climate Change Service (climate.copernicus.eu): a European climate monitoring service with satellite data and open modeling. Free for all uses. NOAA Climate Data (noaa.gov): historical and current climate data from the U.S. National Oceanic and Atmospheric Administration. Global Carbon Project (globalcarbonproject.org): data updated annually on global CO2 emissions and carbon budget. Global Carbon Budget data are open access. IEA World Energy Statistics (iea.org/data-and-statistics): global energy statistics. Some sections are free for non-commercial use. EDGAR (edgar.jrc.ec.europa.eu): a European database of greenhouse gas emissions by country and sector. Completely open. Our World in Data (ourworldindata.org): interactive open access visualizations of data on climate, energy, biodiversity, food, built on verified scientific datasets.