International Green and Sustainable Computing Conference
Quantum Reinforcement Learning for Air Conditioning Control Based on Variational Quantum Circuits
Harshitta Gandhi, Zhipeng Deng
Abstract
We present a novel approach integrating quantum neural networks with reinforcement learning (RL) for house air conditioning control. Our framework employs a quantum deep Q-network (QDQN) RL implemented with PennyLane, leveraging parameterized variational quantum circuits (VQC) as function approximators for Q-values. The agent interacts with simulated indoor thermodynamic modelling, incorporating thermal capacity, heat transfer, and outdoor temperature variations. The action space consists of discrete air conditioning power levels, and the reward function balances comfort, energy, and switching penalties. To stabilize training, we introduce a target network, experience replay, and epsilon-greedy exploration. QDQN encodes the state vector into quantum rotations and applies multi-layer entangling gates, providing a potentially richer representation of the environment compared to classical networks. The QDQN agent uses VQC architecture. It incorporates data re-uploading, parameterized rotations, and strongly entangled qubits to effectively capture inter-feature correlations. We demonstrate the algorithm on episodes with outdoor conditions in both winter and summer conditions, showing convergence to policies that maintain indoor temperatures within setpoint bounds with zero violation rate. To validate the framework in a real-world noise setting, the quantum pipeline is simulated on the IBM Marrakesh system, featuring a 156-qubit Heron r2 processor with a median two-qubit (CZ) error of approximately 2.59 × 10− 3. Our results highlight the promise of quantum RL for real-world controls.