Does the cost-optimal home envelope change when invented fuel prices are replaced by EIA state prices?

What it found

Re-runs house-energy's exhaustive 640-package search in six climates with EIA state residential prices (2025 gas, Jan–Jul 2026 electricity) instead of invented ones. The optimum is unchanged in 10 of 12 cases; the 30-year saving over the baseline moves by −$496 to +$549; advanced 2x6 walls still win, and R-49 attics (27–40 y) and U 0.27 windows (74–107 y) still do not pay. Only fuel prices are sourced; component costs are still invented. Stylised.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
• Tests

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Other research topics

Proper scoring & elicitation28Effort & peer prediction9Verification games & slashing19Detection & tolerances14Markets as routers13Prediction-market design9Paying contributors8Decentralised training systems23Digital twins & sim-to-real164LLM chip design loops40Robot manufacturing loops53Ambient AI assistant46Self-replicating manufacturing34Simulation-first design64Engineered clothing45Task-specific AI accelerators40Algorithmic chip-design loops42Open-source purpose-built robots44The software-engineering loop43Adversarial human imitation41Open-source residential construction41Autonomous multi-angle capture34Sensing, imaging and 3D31Energy supply and dense energy storage39Robot societies among people31Agentic co-design of low-cost robots27Laundry-hanging robots25Machine learning on qualitative data23Robots on the building site27Civilizations & group psychology1History & human sciences1

Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.