The Heat is On

Abstract

This thesis investigates the material demand, critical components, and supply risks associated with the large-scale deployment of heat pumps in the Netherlands towards 2050. As the decarbonisation of the built environment accelerates, the electrification of heating through heat pumps is expected to play a central role. However, this transition will significantly increase the demand for a range of materials, some of which are critical or have supply chains vulnerable to disruption.

The study combines bottom-up data from Environmental Product Declarations (PEP Ecopassports) of commercial heat pump systems with the HESTIA model, a dynamic stock-flow model developed by the Netherlands Environmental Assessment Agency (PBL), to estimate material flows for different types of heat pumps under national climate and energy policy scenarios. The analysis includes both hybrid and all-electric systems across a range of capacities and configurations.

Key materials identified include copper, aluminium, steel, and plastics, along with critical raw materials such as neodymium, lithium, and specific refrigerants. Special attention is given to components like compressors, heat exchangers, printed circuit boards, and permanent magnets, which often contain strategic or scarce elements. The study assesses these materials and components for criticality based on European Commission classifications, recyclability, geopolitical risk, and production concentration.

Beyond quantifying material demand, the thesis evaluates the implications of supply constraints and explores potential strategies for circularity. This includes the reuse of components, design for disassembly, improved recycling infrastructure, and substitution with less critical materials. Expert interviews and industry reports are used to validate assumptions and identify barriers and opportunities in the implementation of these circular approaches.

The results highlight a growing tension between rapid electrification goals and the limited scalability of material supply chains. Without proactive strategies, the Netherlands risks exposure to international supply shocks, environmental pressures from virgin extraction, and the accumulation of waste. The findings emphasise the need to integrate circular economy principles early in the heat pump market's expansion and to align energy transition planning with resource availability.

Overall, this research provides a comprehensive material flow analysis for Dutch heat pumps, identifies key risks, and outlines circular pathways to mitigate them. It offers actionable insights for policymakers, manufacturers, and energy system modellers working to future-proof the transition to low-carbon heating.