GreenOS is an AI-powered SaaS platform for real-time energy and carbon management without sensors. Traditional Building Energy Management Systems(BEMS) face major hurdles, including high installation costs from sensors and devices and a shortage of specialized staff to manage complex operations. Adoption is limited, especially in small to medium commercial and older buildings, often resulting in systems used mainly for monitoring rather than active optimization. GreenOS eliminates hardware requirements through sensorless Non-Intrusive Load Monitoring (NILM) and leverages proprietary deep learning models for accurate device-level energy disaggregation and demand prediction. Its card dashboard, GPT-based chatbot, and automated ESG reporting reduce operational burden and expertise. Our technologies are protected by 10 intellectual property filings and have earned 3 awards from the Ministry of Infrastructure in Korea, reinforcing originality and credibility. GreenOS removes traditional BEMS barriers, making energy and carbon management accessible across diverse environments while driving savings and accelerating carbon reduction.