GenAI interfaces like ChatGPT , Google Gemini , and Claude are clean and instant. But behind every prompt lies power-dense GPU clusters drawing electricity and evaporative cooling water.

To bring physical transparency to AI interactions without tracking users or slowing down the browser, I built EcoPrompt — an open-source, 100% client-side Chrome extension (Manifest V3).

🌿 What EcoPrompt Tracks

When you hit Enter on ChatGPT, Gemini, or Claude, EcoPrompt displays a non-intrusive in-page toast estimating:

🍃 Carbon Footprint (g CO₂e): Real-time emissions based on datacenter PUE and energy grid averages.

💧 Water Consumption (mL): Direct evaporative cooling plus indirect electricity water draw.

⚡ Active Energy (Wh): Compute energy required for prompt prefill and decode cycles.

💶 API Cost Equivalence: Baseline token computation rates across model tiers.

🛠️ Technical Constraints & Architecture Choices

Building a extension for developers required strict design decisions:

1.…