Optimization of phase change material integration in residential building envelopes in cold climates: energy and economic performance analysis
Notice bibliographique
Résumé
Phase Change Materials (PCMs) are increasingly explored in building energy research for their ability to reduce indoor temperature fluctuations and lower energy demands through latent heat storage. This thesis investigates PCM integration in residential building envelopes across Canadian cold climates, combining energy performance optimization with economic feasibility assessments. Two projects are presented: the first focused on identifying energy-optimal PCM configurations for a residential building under constant and intermittent operations, while the second expands the investigation into multi-objective optimizations across multiple cities and envelope types, considering techno-economic trade-offs. The first project examines a single-family residential prototype located in Edmonton, Alberta, under two typical internal operation schedules: constant (24-hour conditioned) and intermittent (nighttime-only). A co-simulation platform integrating EnergyPlus and GenOpt is used to optimize the midpoint melting temperature (Tₘ) of interior-installed PCMs for annual heating, cooling, and total energy load minimization. Results show that interior installation significantly outperforms exterior placement due to better thermal coupling with indoor spaces. The optimal Tₘ values were found to be 21.71 °C for steady and 22.04 °C for intermittent operation, achieving total energy savings of 6.65 percent and 5.21 percent, respectively. Cooling energy savings were notably higher under intermittent operation, reaching up to 28.42 percent, reflecting increased PCM activation during unoccupied daytime periods. Daily and hourly simulation analyses further demonstrate the materials' buffering effect in transitional seasons. While winter savings remain modest due to limited phase-change activation, PCM layers substantially enhance indoor thermal stability, supporting improved occupant comfort and energy demand flexibility. These results highlight the importance of aligning Tₘ with thermostat settings, ideally within 0.5 °C of the heating setpoint or 1 °C to 2 °C below the cooling setpoint. The second project develops a techno-economic optimization framework for PCM-integrated multi-family buildings, applied to four representative Canadian cities: Vancouver, Toronto, Montreal, and Edmonton. Thirteen PCM-related design variables, including temperature-enthalpy curves, installation positions, and layer thickness, are optimized using the NSGA-II coupled with EnergyPlus simulations and a custom data-logging mechanism in MATLAB. Results reveal a consistent trade-off between the source energy use and total cost, forming a concave Pareto front. Optimal solutions favor interior PCM placement, narrow melting ranges between 1 °C and 3 °C, and midpoint melting temperatures between 21 °C and 24 °C. A key contribution of this work is the detailed HVAC analysis, particularly regarding cooling performance. PCM-enhanced envelopes reduce peak cooling loads, extend cooling durations, and flatten daily load profiles, promoting thermal load redistribution to off-peak hours. This redistribution supports the use of part-load-efficient HVAC systems and helps alleviate peak period demand, although the overall coefficient of performance (COP) showed minimal increase under the single-speed DX cooling system. Cooling system sizing simulations show that PCM application can reduce design capacities by up to 25 percent. However, economic analysis indicates that most current PCM configurations remain cost-prohibitive with high payback periods, but mild PCM use cases exhibit improved cost-effectiveness. Benefit-cost ratio analysis across cities and envelope types identified the investment priorities for different cities and envelope types, favoring high utility price cities and exterior wall assemblies. Break-even price analysis further indicates that viable PCM unit costs should fall below 1 Canadian dollar per kilogram to enable broader adoption. In conclusion, this thesis presents a comprehensive evaluation of PCM-enhanced residential building envelopes in cold climates. By combining energy and economic optimization, it provides practical insights into how PCM design, building operation patterns, and HVAC interactions influence performance and cost. The findings support future development of energy-flexible, thermally stable, and cost-efficient building design strategies.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,002 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».