Performance Assessment of a Novel Transcritical CO2 Pumpless Rankine Cycle for Small-Scale Solar Power Generation in Building Stocks
Source abstract
Abstract
This study introduces a novel transcritical CO2 pumpless Rankine power generation cycle based on the thermal compression concept, utilizing low-temperature renewable sources. The investigated theoretical system consists of a 5 kWe unit incorporating the aforementioned working cycle coupled with a 50 m2 evacuated tube solar collector arrangement installed on the rooftop of a multifamily house in Athens, Greece. The proposed innovative configuration is parametrically analyzed for different hot water inlet temperature levels ranging from 70 to 120 °C and its efficiency is compared to the typical Organic Rankine Cycle (ORC) topology employing different conventional refrigerants. The energetic assessment is made using validated mathematical models developed in MATLAB integrating the CoolProp library. The derived results show that the investigated topology increases the performance figures compared to the baseline system for all the examined refrigerants, leading up to over 15% thermal efficiency enhancement for operation under low heat source temperatures. Finally, the year-round operation of the proposed system generates up to 5221 kWh/year for the building.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Thermodynamic and Exergetic Analyses of Power and Cooling Systems · Adsorption and Cooling Systems · Refrigeration and Air Conditioning Technologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Energy and Environmental Research Laboratory, Department of Agricultural Development, Agri-Food and Natural Resources Management, National and Kapodistrian University of Athens, 34400 Psachna, Greece
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