arXiv AI

The Language-Energy Divide: Measuring Energy Costs of Multilingual LLM Inference

The paper investigates the energy costs of multilingual large language model (LLM) inference, revealing significant disparities across languages. Using the ML.Energy framework, the authors find that energy consumption per output token can differ by up to 8.3×, and total energy for a fixed request set can vary up to 179×, with English being the cheapest and Pashto the most expensive. The study attributes these differences to higher per-token costs for complex or rare scripts and longer outputs for low‑resource languages, and notes that high‑energy languages also tend to have lower task accuracy.

arXiv AI
2d ago

AssameseLM-E2B: An Open-Weight Assamese Language Model for Efficient Consumer-Grade Deployment

The paper introduces AssameseLM-E2B, a 2‑billion‑parameter language model tailored for the low‑resource Assamese language, and its instruction‑tuned variant AssameseLM-E2B‑it. Built on the Gemma‑4 architecture, it uses an expanded byte‑level BPE vocabulary that cuts tokenization overhead by nearly 500 % compared with multilingual baselines, and employs a parameter‑efficient Continual Pre‑Training pipeline with Hybrid LoRA followed by supervised fine‑tuning on a balanced, multi‑domain dataset. Evaluation shows strong performance with a Bits‑per‑Byte score of 0.7488 on FLORES‑200, a 96.7 % RAG score, and 100 % refusal accuracy on adversarial prompts, highlighting the effectiveness of parameter‑efficient adaptation for locally deployable models under constrained resources.

By Pragyan Phukan
arXiv AI
Oct 26

Green Code or Costly Code? Evaluating the Energy Costs of Iterative LLM-Based Code Optimizations

Large Language Models (LLMs) are increasingly used to optimize code for performance, but this study shows that such optimizations often increase energy consumption rather than reduce it. Across 11 open‑source models and 1,000 benchmark problems, inference energy ranged from 0.79 to 8.68 MJ, and 42 of 44 configurations produced code that used 4% to 886% more energy than human‑written reference solutions. Mixture‑of‑Experts architectures and token‑limit constraints can reduce inference energy, yet performance‑optimized code remains energy‑heavier, indicating that speed and sustainability are not always aligned goals.

By Sadra Emami, Benjamin Weigell, Mohammad Reza Mousavi, Gunel Jahangirova, Hugo Araujo, Bernhard Bauer
arXiv Computation and Language
Sep 3

How Do Prompt Variations Affect Energy Consumption in On-Device LLMs?

The paper investigates how prompt design influences energy consumption in on-device large language models (LLMs). It examines two prompt properties—cognitive load and phrasing pattern—across various datasets, models, and devices, using phase-level profiling to separate prefill and decode energy. Findings show that cognitive load mainly affects energy per token, while phrasing pattern influences energy mainly through token usage, and that prompt design reshapes the energy-quality trade‑off differently for each model.

By Wei Hu, Xiaolong Tu, Dawei Chen, Yitao Chen, Kyungtae Han, Haoxin Wang
arXiv AI
Oct 31

The Real Cost of Context: Predicting Compute Time and Energy Consumption in LLM Prefill and Decode Phases

The paper investigates how token length affects compute time and energy usage in Large Language Models, focusing on both prefill (input) and decode (output) phases. It finds that decode energy scales linearly with output length, while prefill energy shows both linear and quadratic scaling with input length, highlighting the importance of large input contexts in agentic workflows. The study also demonstrates that compute time can reliably proxy energy consumption when direct measurements are unavailable, providing a framework for more sustainable AI deployment.

By Lars Krupp, Daniel Gei{\ss}ler, Francisco M. Calatrava-Nicolas, Stefan Gerd Fritsch, Paul Lukowicz, Jakob Karolus