Does a temperature-dependent heat-pump COP change how much more a heat pump can cost than gas before gas wins?

What it found

Fits an hourly temperature distribution to each climate's degree days and lets heating COP fall with temperature (an assumed curve, floored at 1), then reruns the break-even premium of house-hvacnpc. Seasonal COP is 4.01 in Miami to 2.30 in Duluth, so the constant 2.5 understated the heat pump in the South: the break-even premium rises to $156, $952 and $1,979 in Miami, Houston and Atlanta and falls to −$8,050 in Duluth. Signs do not change; Duluth spans −$1,961 to −$16,661 across nine curves. The curve is assumed, not sourced, and the normal temperature model is crude. 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.