PDF Publication Title:
Text from PDF Page: 007
whereby the capital cost is calculated thousands of times using a random set of suitable cost correlations. A probability distribution of costs is then obtained, from which statistics such as the mean and standard deviation (or confidence intervals) can be found. This techno-economic computational model will be fully documented in a forthcoming journal article. Numerous configurations for sCO2-PTES exist, which can employ different combinations of recuperators or multiple storage tanks [10]. In this article, the system is intended to be integrated with a CSP plant that uses an sCO2 recompression cycle as the heat engine and nitrate molten salts for the hot storage. The charging cycle is therefore configured to share the storage components and recuperators in an effort to reduce the cost of the system. The temperature-entropy diagram is illustrated in Fig. 2 and the charging cycle follows the same process as the ideal-gas PTES cycle: the only difference is that two recuperators are used rather than one. Since the expander inlet is close to the carbon dioxide critical point, the minimum temperature of the cycle is higher than in ideal-gas PTES, and as a result a cheap cold storage fluid, such as water, can be used. During discharge, the thermal energy in the hot storage is discharged through an sCO2-recompression cycle. Rather than rejecting heat to the environment, waste heat is instead transferred into the cold storage, therefore completing the PTES cycle. Using cold storage as the heat sink has the advantage that the temperature is more stable (and often lower) than the ambient temperature, and that pumping the liquid storage fluid incurs lower parasitic losses than air fans in an air-cooled heat rejection system. FIGURE 2: Temperature-entropy diagram of sCO2-PTES which uses an sCO2¬ recompression cycle during discharge. TABLE 1: Assumptions made for nominal PTES designs Hot storage Recompressor Cold storage Assumptions Polytropic efficiency, 𝜂𝜂 % 90.0 Pressure loss, 𝑓𝑓 % 1.0 𝑝𝑝 Effectiveness, 𝜀𝜀 - 0.97 Power output MWe 100 Storage duration h 10 4 This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications.PDF Image | Supercritical CO2 Heat Pumps Concentrating Solar Power
PDF Search Title:
Supercritical CO2 Heat Pumps Concentrating Solar PowerOriginal File Name Searched:
77955.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)