District heating and cooling networks play a crucial role in modern urban energy systems by centralizing the generation and distribution of thermal energy, thereby potentially reducing energy consumption and environmental impacts. However, the environmental performance of district heating and cooling networks is highly dependent on the technologies used for heat and cooling generation. This study conducts a comprehensive life cycle assessment of three key technologies: natural gas boilers, heat pumps, and cooling towers, with the primary goal of developing empirical relationships between nominal power and environmental burdens. The life cycle assessment follows the International Organization for Standardization 14040 and 14044 standards, utilizing data from the Ecoinvent 3.10 database and the Environmental Footprint 3.1 method. The functional unit is defined as the heating and cooling supplied to district heating and cooling networks for 7 000 equivalent hours for heating and 1 760 equivalent hours for cooling per year, calculated over a 60-year service life and a 50-year study period, with replacement in mind. The functional unit was selected to establish an empirical relationship between the nominal power of energy generation systems and their associated environmental burdens. This relationship will facilitate the assessment of environmental impacts during both the embodied and operational phases of these systems. The environmental profiles analysed included the 16 impact categories of the Environmental Footprint 3.1 characterization method with a focus on climate change, freshwater ecotoxicity, and ozone depletion. The results indicate that the use phase is the primary contributor to climate change for natural gas boilers (99%), heat pumps (94.5%) and cooling towers (99%), while the raw material acquisition and manufacturing phases are significant contributors in embodied environmental impact for all generation systems. This study established empirical relationships between energy system power and environmental impact, aiding in the development of future assessment tools for district heating and cooling networks.
Le reti di teleriscaldamento e teleraffrescamento svolgono un ruolo cruciale nei moderni sistemi energetici urbani, centralizzando la generazione e la distribuzione di energia termica, riducendo così potenzialmente il consumo di energia e gli impatti ambientali. Tuttavia, la performance ambientale delle reti di teleriscaldamento e teleraffrescamento dipende fortemente dalle tecnologie utilizzate per la generazione di calore e raffreddamento. Questo studio conduce una valutazione del ciclo di vita (LCA) completa di tre tecnologie chiave: caldaie a gas naturale, pompe di calore e torri di raffreddamento, con l'obiettivo primario di sviluppare relazioni empiriche tra la potenza nominale e i carichi ambientali. La valutazione del ciclo di vita segue gli standard ISO 14040 e 14044, utilizzando dati dal database Ecoinvent 3.10 e dal metodo Environmental Footprint 3.1. L'unità funzionale è definita come il riscaldamento e il raffreddamento forniti alle reti di teleriscaldamento e teleraffrescamento per 7.000 ore equivalenti per il riscaldamento e 1.760 ore equivalenti per il raffreddamento all'anno, calcolati su una durata di servizio di 60 anni e un periodo di studio di 50 anni, considerando la sostituzione. L'unità funzionale è stata selezionata per stabilire una relazione empirica tra la potenza nominale dei sistemi di generazione di energia e i loro carichi ambientali associati. Questa relazione faciliterà la valutazione degli impatti ambientali sia durante le fasi incorporate che operative di questi sistemi. I profili ambientali analizzati includevano le 16 categorie di impatto del metodo di caratterizzazione Environmental Footprint 3.1, con particolare attenzione ai cambiamenti climatici, all'ecotossicità dell'acqua dolce e potenziale di riduzione dello strato di ozono. I risultati indicano che la fase di utilizzo è il principale contributore ai cambiamenti climatici per le caldaie a gas naturale (99%), le pompe di calore (94,5%) e le torri di raffreddamento (99%), mentre le fasi di acquisizione delle materie prime e di produzione sono contributori significativi all'impatto ambientale incorporato per tutti i sistemi di generazione. Questo studio ha stabilito relazioni empiriche tra la potenza del sistema energetico e l'impatto ambientale, aiutando nello sviluppo di futuri strumenti di valutazione per le reti di teleriscaldamento e teleraffrescamento.
Empirical relationship between nominal capacity of generation system to environmental burdens.
Maheshwari, Anoop
2024/2025
Abstract
District heating and cooling networks play a crucial role in modern urban energy systems by centralizing the generation and distribution of thermal energy, thereby potentially reducing energy consumption and environmental impacts. However, the environmental performance of district heating and cooling networks is highly dependent on the technologies used for heat and cooling generation. This study conducts a comprehensive life cycle assessment of three key technologies: natural gas boilers, heat pumps, and cooling towers, with the primary goal of developing empirical relationships between nominal power and environmental burdens. The life cycle assessment follows the International Organization for Standardization 14040 and 14044 standards, utilizing data from the Ecoinvent 3.10 database and the Environmental Footprint 3.1 method. The functional unit is defined as the heating and cooling supplied to district heating and cooling networks for 7 000 equivalent hours for heating and 1 760 equivalent hours for cooling per year, calculated over a 60-year service life and a 50-year study period, with replacement in mind. The functional unit was selected to establish an empirical relationship between the nominal power of energy generation systems and their associated environmental burdens. This relationship will facilitate the assessment of environmental impacts during both the embodied and operational phases of these systems. The environmental profiles analysed included the 16 impact categories of the Environmental Footprint 3.1 characterization method with a focus on climate change, freshwater ecotoxicity, and ozone depletion. The results indicate that the use phase is the primary contributor to climate change for natural gas boilers (99%), heat pumps (94.5%) and cooling towers (99%), while the raw material acquisition and manufacturing phases are significant contributors in embodied environmental impact for all generation systems. This study established empirical relationships between energy system power and environmental impact, aiding in the development of future assessment tools for district heating and cooling networks.| File | Dimensione | Formato | |
|---|---|---|---|
|
Master_s Thesis_Anoop_10898534.pdf
accessibile in internet per tutti
Dimensione
1.96 MB
Formato
Adobe PDF
|
1.96 MB | Adobe PDF | Visualizza/Apri |
I documenti in POLITesi sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/10589/234820