Energies, Free Full-Text
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Energies, Free Full-Text
One of the biggest obstacles to economic profitability of solar water heating systems is the investment cost. Retrofitting existing domestic hot water heaters when a new solar hot water system is installed can reduce both the installation and material costs. In this study, retrofitting existing water heaters for solar water heating systems in Swedish single-family houses was theoretically investigated using the TRNSYS software. Four simulation models using forced circulation flow with different system configurations and control strategies were simulated and analysed in the study. A comparison with a standard solar thermal system was also presented based on the annual solar fraction. The simulation results indicate that the retrofitting configuration achieving the highest annual performance consists of a system where the existing tank is used as storage for the solar heat and a smaller tank with a heater is added in series to make sure that the required outlet temperature can be met. An external heat exchanger is used between the collector circuit and the existing tank. For this retrofitted system an annual solar fraction of 50.5% was achieved. A conventional solar thermal system using a standard solar tank achieves a comparable performance for the same total storage volume, collector area and reference conditions.
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Energy systems and 24/7 carbon free energy
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Energy Level Vector Art, Icons, and Graphics for Free Download
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Energies, Free Full-Text
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Garabed free-energy generator. February 19, 1926. -- Referred to
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Accurate determination of solvation free energies of neutral
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Sensors, Free Full-Text
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A Path to Pollution-Free Buildings: Meeting Xcel's 2030 Goals
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Premium PSD Energy text effect
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Molecular dynamics simulations and drug discovery
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Instantaneous Power Theory And Applications To Power Conditioning
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Inner pore hydration free energy controls the activation of big
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Full energy icon with head and battery Royalty Free Vector
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The free energy principle made simpler but not too simple
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1 FREE ENERGY GENERATOR at Lookout Landing provides full coverage
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The free world needs to grow up about energy policy – Orange