Practitioner Calculates Real Electricity Costs for Running Qwen3.5 27B Locally — Compares to API Pricing

r/LocalLLaMA·low signal

A detailed r/LocalLLaMA post (79 upvotes, 50 comments) calculated the actual electricity costs of running Qwen3.5 27B locally using vLLM, measuring tokens/second for both prompt processing and generation alongside real power consumption. The analysis compared local inference costs per million tokens against API pricing ($0.195–$0.30/M input, $1.56–$2.40/M output on OpenRouter), providing the kind of empirical data local-inference builders need for ROI calculations on hardware purchases.