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High Temperature Heat Pumps: Market Overview, Stateof the Art, Research Status, Refrigerants, and Application Potentials

TL;DR: A review of the state of the art and the current research activities of high temperature heat pumps with heat sink temperatures in the range of 90 to 160°C can be found in this paper.
Abstract: Abstract This study reviews the current state of the art and the current research activities of high temperature heat pumps (HTHPs) with heat sink temperatures in the range of 90 to 160 °C. The focus is on the analysis of the heat pump cycles and the suitable refrigerants. More than 20 HTHPs from 13 manufacturers have been identified on the market that are able to provide heat sink temperatures of at least 90 °C. Large application potentials have been recognized particularly in the food, paper, metal and chemical industries. The heating capacities range from about 20 kW to 20 MW. Most cycles are single-stage and differ primarily in the refrigerant (e.g. R245fa, R717, R744, R134a or R1234ze(E)) and compressor type used. The COPs range from 2.4 to 5.8 at a temperature lift of 95 to 40 K. Several research projects push the limits of the achievable COPs and heat sink temperatures to higher levels. COPs of about 5.7 to 6.5 (at 30 K lift) and 2.2 and 2.8 (70 K) are achieved at a sink temperature of 120 °C. The refrigerants investigated are mainly R1336mzz(Z), R718, R245fa, R1234ze(Z), R600, and R601. R1336mzz(Z) enables to achieve exceptionally high heat sink temperatures of up to 160 °C.
Citations
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Journal ArticleDOI
16 Apr 2021
TL;DR: A novel overview of the considerations for deploying these DAC technologies, including concepts for learning-by-doing that may drive down costs and material requirements for scaling up DAC technologies are provided.
Abstract: Direct air capture (DAC) can provide an impactful, engineered approach to combat climate change by removing carbon dioxide (CO2) from the air. However, to meet climate goals, DAC needs to be scaled at a rapid rate. Current DAC approaches use engineered contactors filled with chemicals to repeatedly capture CO2 from the air and release high purity CO2 that can be stored or otherwise used. This review article focuses on two distinctive, commercial DAC processes to bind with CO2: solid sorbents and liquid solvents. We discuss the properties of solvents and sorbents, including mass transfer, heat transfer and chemical kinetics, as well as how these properties influence the design and cost of the DAC process. Further, we provide a novel overview of the considerations for deploying these DAC technologies, including concepts for learning-by-doing that may drive down costs and material requirements for scaling up DAC technologies.

137 citations

Journal ArticleDOI
TL;DR: In this article, the authors present an extensive review of previous works on several aspects of heat pumps, including their role in the decarbonisation of the heating sector, and their roles in terms of adding flexibility to renewable-rich systems and carbon abatement are examined.
Abstract: Addressing the growing concerns of climate change necessitates the decarbonisation of energy sectors globally. Heating is the largest energy end-use, accounting for almost half of total energy consumption in most countries. This paper presents an extensive review of previous works on several aspects of heat pumps, including their role in the decarbonisation of the heating sector. In addition, themes related to recent technological advances of heat pumps, as well as, their roles in terms of adding flexibility to renewable-rich systems and carbon abatement are examined. Challenges and barriers facing large-scale deployment of heat pumps are identified. Generally, as the share of renewables in the energy mix increases, heat pumps can play a role in addressing a multitude of problems induced by climate change. The potential of heat pumps to abate emissions, however, is highly dependent on the type of technology, location and electricity mix. Heat pumps can be a source of flexibility in the power system and can upgrade waste heat to provide low-cost heating in district heating networks. They are environment friendly and provide a viable pathway for decarbonising the heating sector. However, economic, regulatory, structural and infrastructural barriers exist, which may hinder heat pump integration rate.

124 citations

Journal ArticleDOI
TL;DR: In this paper, the applicability of modern fluids as drop-in replacements for R245fa in existing organic rankine cycle (ORC) systems was investigated, and all three fluids were tested in an ORC system under a wide range of operation conditions.

105 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present the results from a comprehensive bottom-up analysis of the energy use in eleven industrial sectors (accounting for 92% of Europe's industry CO2 emissions), and estimate the technological potential for industry electrification in three stages.
Abstract: The decarbonisation of industry is a bottleneck for EU's 2050 target of climate neutrality. Replacing fossil fuels with low-carbon electricity is at the core of this challenge; however, the aggregate electrification potential and resulting system-wide CO2 reductions for diverse industrial processes are unknown. Here, we present the results from a comprehensive bottom-up analysis of the energy use in eleven industrial sectors (accounting for 92% of Europe's industry CO2 emissions), and estimate the technological potential for industry electrification in three stages. 78% of the energy demand is electrifiable with technologies that are already established, while 99% electrification can be achieved with the addition of technologies currently under development. Such a deep electrification reduces CO2 emissions already based on the carbon intensity of today's electricity (~300 gCO2/kWhel). With an increasing decarbonisation of the power sector (IEA: 12 gCO2/kWhel in 2050), electrification could cut CO2 emissions by 78%, and almost entirely abate the energy-related CO2 emissions, reducing the industry bottleneck to only residual process emissions. Despite its decarbonisation potential, the extent to which direct electrification will be deployed in industry remains uncertain and depends on the relative cost of electric technologies compared to other low-carbon options.

88 citations

Journal ArticleDOI
TL;DR: In this paper, the traditional working fluids used in heat pumps generally have a high global warming potential and produce a significant greenhouse effect when leaked, therefore, low-GWP (GWP) working fluids can be used.
Abstract: Global warming is a major environmental concern, which significantly impacts ecological systems and the safety of coastal cities. To address global warming, effective methods must be adopted to reduce greenhouse gas emissions and the consumption of fossil fuels. Vapor compression heat pumps offer an effective way to recover energy from waste heat sources and reduce primary energy consumption. However, the traditional working fluids used in heat pumps generally have a high global warming potential (GWP) and produce a significant greenhouse effect when leaked. Therefore, low-GWP (GWP

82 citations

References
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01 Jan 1997
TL;DR: This informal consolidated text of the Kyoto Protocol incorporates the Amendment adopted at the eighth session of the Conference of the Parties serving as the meeting of the parties to Kyoto Protocol (Doha Amendment).
Abstract: ____________________________________________ *This informal consolidated text of the Kyoto Protocol incorporates the Amendment adopted at the eighth session of the Conference of the Parties serving as the meeting of the Parties to the Kyoto Protocol (Doha Amendment). The Doha Amendment has not, as yet, entered into force. The informal consolidated text therefore has no official legal status and has been prepared by the secretariat solely to assist Parties. 1 KYOTO PROTOCOL TO THE UNITED NATIONS FRAMEWORK CONVENTION ON CLIMATE CHANGE*

5,435 citations

Book ChapterDOI
01 Jan 2014
TL;DR: Myhre et al. as discussed by the authors presented the contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) 2013: Anthropogenic and Natural Radiative forcing.
Abstract: This chapter should be cited as: Myhre, G., D. Shindell, F.-M. Bréon, W. Collins, J. Fuglestvedt, J. Huang, D. Koch, J.-F. Lamarque, D. Lee, B. Mendoza, T. Nakajima, A. Robock, G. Stephens, T. Takemura and H. Zhang, 2013: Anthropogenic and Natural Radiative Forcing. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Coordinating Lead Authors: Gunnar Myhre (Norway), Drew Shindell (USA)

3,684 citations

Journal ArticleDOI
TL;DR: In this paper, the authors presented the characteristics of medium to medium-high temperature solar collectors and an overview of efficiency and cost of existing technologies for industrial process heat applications in the Mediterranean climate.

513 citations

01 Jan 2009
TL;DR: This eighth edition of the Handbook incorporates the full text of the treaty and an updated list of all decisions adopted by the Meeting of the Parties to the Montreal Protocol (covering policy, legal, non-compliance, science and technology, and other technical issues associated with the implementation of and compliance with the Protocol), along with other relevant information up to 2008.
Abstract: Since the Montreal Protocol came into force in 1989, it has been amended on four occasions and adjusted six times, in order to strengthen its provisions and accelerate the recovery of the ozone layer. In addition, the Parties have adopted a wide range of decisions at their annual meetings of the Parties, clarifying issues relating to the protection of the ozone layer and strengthening the implementation of the Protocol. This eighth edition of the Handbook incorporates the full text of the treaty and an updated list of all decisions adopted by the Meeting of the Parties to the Montreal Protocol (covering policy, legal, non-compliance, science and technology, and other technical issues associated with the implementation of and compliance with the Protocol), along with other relevant information up to 2008. It is the first edition published after the Protocol achieved universal participation by 196 Parties on 16 September 2009. The handbook can be downloaded from: http://ozone.unep.org/Publications/MP_Handbook/MP-Handbook-2009.pdf.

218 citations

Journal ArticleDOI
TL;DR: In this paper, the authors evaluated the performance of low global warming potential refrigerants R1234ze(E) and R12 34ze(Z) for high-temperature heat pump systems in industrial applications.
Abstract: Low global warming potential refrigerants R1234ze(E) and R1234ze(Z) are anticipated to be the refrigerants of choice for high-temperature heat pump systems in industrial applications. Their thermodynamic attributes are thermodynamically, experimentally, and numerically assessed in this study. The thermodynamic assessment indicates that the theoretical coefficients of performances (COP) are maximized at a condensation temperature approximately 20 K below the critical temperatures for each refrigerant. However, when the volumetric capacity is inadequate, the actual COP differs from the theoretical COP because of the large pressure drop. The breakdown of irreversible losses, which are experimentally quantified at a condensation temperature of 75 °C, results in the largest portion of the total pressure drop. The simulation results obtained at condensation temperatures of 105 and 125 °C indicate higher COPs than that at 75 °C for R1234ze(Z). The major factor is the reduction in the irreversible loss caused by the pressure drop. The above assessments demonstrate that R1234ze(Z) is suitable for high-temperature applications rather than in typical air conditioners.

161 citations