Internet of Things deployments create complex environmental impacts across manufacture, operation, networking and end-of-life. Quantifying those impacts requires metrics that capture greenhouse gas emissions, energy use, material flows and waste, and that are applied with standardized lifecycle methods. The International Organization for Standardization ISO 14040 and ISO 14044 provide the methodological backbone for such assessments, guiding transparent Life Cycle Assessment procedures.
Core lifecycle metrics
The most transferable metric is Global Warming Potential expressed as carbon dioxide equivalents per device or per device-year; this follows standard LCA practice and enables comparison of manufacturing, usage and network emissions. Complementary energy metrics include Cumulative Energy Demand and energy intensity per data unit such as joules per gigabyte, which help separate device standby and active consumption from network and cloud processing. Material-focused measures include material criticality and primary resource depletion, which track the mass and scarcity-weighted impact of rare earths and conflict minerals embedded in sensors and modules. End-of-life performance is quantified by recycling rate, collection rate, and recycled content percentage, metrics emphasized in the Global E-waste Monitor by Christopher C. Forti United Nations University to highlight the scale and management gaps in electronic waste. Metrics for circularity and durability — such as average product lifetime, repairability score and fraction of components designed for reuse — translate design choices into measurable lifecycle outcomes.
Relevance, causes, and consequences
These metrics matter because IoT impacts arise from distinct causes: high-volume manufacturing in global supply chains, continuous energy draw of always-on devices, and network/cloud processing that shifts emissions to data centers and transmission infrastructure. Fatih Birol International Energy Agency has highlighted how network and data center energy trends affect overall sector emissions, making per-GB energy metrics especially relevant. Consequences are environmental and social: greenhouse gas emissions, increased e-waste burden with informal recycling risks in many territories, and pressure on mineral supplies in culturally and geopolitically sensitive regions. Regional electricity mix, regulatory regimes, and informal recycling practices strongly influence metric outcomes and policy choices. Combining standardized LCA outputs with operational measures like energy intensity per user and circularity indicators gives the most actionable picture, enabling manufacturers, operators and regulators to target design changes, extend product life, and improve recycling to lower the overall lifecycle footprint.