The impact of heatwave-driven air conditioning adoption on electricity demand: A spatio-temporal case study for Germany

TL;DR

This study introduces a new method to estimate how heatwave-driven adoption of air conditioning in Germany could significantly increase electricity demand, especially during peak hours, posing challenges for power grid stability.

Contribution

The paper develops a novel high-resolution approach to estimate AC-related electricity demand during heatwaves, combining diverse data sources for detailed spatial and temporal analysis.

Findings

Peak demand could increase by over 12.9 GW during heatwaves.

Urban hot-spots may experience demand increases up to 5.2 MW per km².

Pronounced afternoon peaks coincide with reduced solar power generation.

Abstract

Intensifying heatwaves driven by climate change are accelerating the adoption of mobile air conditioning (AC) systems. A rapid mass adoption of such AC systems could create additional stress on electricity grids and the power system. This study presents a novel method to estimate the electricity demand from AC systems both at the system level and at high temporal and spatial granularity. We apply the method to a near-future heatwave scenario in Germany in which household AC adoption increases from the current 19% to 35% during a heatwave similar to the one of July 2025. We analyze the effects for 196,428 grid cells of one square kilometer across Germany, by combining weather data, census data, socio-demographic assumptions, mobility patterns, and temperature-dependent AC activation functions. We find that electricity demand of newly purchased mobile AC systems could increase the peak load by over 12.9 GW, with urban hot-spots reaching 5.2 MW per square kilometer. The temporal pattern creates a pronounced afternoon peak that coincides with lower photovoltaic generation, potentially exacerbating power system stability challenges. Our findings underscore the urgency for proactive energy system planning to manage emerging demand peaks.