In: Proceedings of the Estonian Academy of Sciences: official publication of Tallinn Technical University and the Estonian Academy of Sciences = Eesti Teaduste Akadeemia toimetised = Izvestija Akademii Nauk Ėstonii. Engineering = tehnikateadused = techničeskie nauki, Band 3, Heft 2, S. 75
This work was partially funded by the Ministerio de Ciencia, Innovación y Universidades de España (RTI2018-093849-B-C31). The author would like to thank the Catalan Government for the quality accreditation given to her research group GREiA (2017 SGR 1537). GREiA is a certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme.
Thermal energy storage technologies need to be further developed and need to become an integral component in the future energy system infrastructure to meet variations in both the availability and demand of energy. The main objectives of project HEATSTORE are to lower the cost, reduce risks, improve the performance of high temperature (~25°C to ~90°C) underground thermal energy storage (HT-UTES) technologies and to optimize heat network demand side management (DSM). This is primarily achieved by 6 new demonstration pilots and 8 case studies of existing systems with distinct configurations of heat sources, heat storage and heat utilization. It will advance the commercial viability of HT-UTES technologies and, through an optimized balance between supply, transport, storage and demand, enable geothermal energy production to reach its maximum deployment potential in the European energy transition. HEATSTORE is a project under the GEOTHERMICA – ERA NET Cofund and contributes to achieving the several objectives of accelerating the uptake of geothermal energy by 1) advancing and integrating different types of underground thermal energy storage (UTES) in the energy system, 2) providing a means to maximize geothermal heat production and optimize the business case of geothermal heat production doublets, 3) addressing technical, economic, market, environmental, regulatory and policy aspects that are necessary to support efficient and cost-effective deployment of UTES technologies in Europe. The 3-year project started in 2018 will stimulate a fast-track market uptake in Europe, promoting development from demonstration phase to commercial deployment within 2 to 5 years, and provide an outlook for utilization potential towards 2030 and 2050. The HEATSTORE consortium brings together 23 contributing partners (mix of scientific research institutes and private companies) from 9 countries. ; HEATSTORE (170153-4401) is one of nine projects under the GEOTHERMICA – ERA NET Cofund aimed at accelerating the uptake of geothermal energy. The GEOTHERMICA project is supported by the European Union's HORIZON 2020 programme for research, technological development and demonstration under grant agreement No 731117. ; Postprint (published version)
In this research, cooling system optimization using thermal energy storage (TES) in shopping center buildings was investigated. Cooling systems in commercial buildings account for up to 50% of their total energy consumption. This incurs high electricity costs related to the tariffs determined by the Indonesian government with the price during peak hours up to twice higher than during off-peak hours. Considering the problem, shifting the use of electrical load away from peak hours is desirable. This may be achieved by using a cooling system with TES. In a TES system, a chiller produces cold water to provide the required cooling load and saves it to a storage tank. Heat loss in the storage tank has to be considered because greater heat loss requires additional chiller capacity and investment costs. Optimization of the cooling system was done by minimizing the combination of chiller capacity, cooling load and heat loss using simplex linear programming. The results showed that up to 20% electricity cost savings can be achieved for a standalone shopping center building.
Abstract The industrial cold stores can act as thermal energy stores that can store the energy as passive thermal energy. The cold stores have intentions to contribute with flexible consumption but need some knowledge about the potential. By cooling the cold stores and the goods further down when the energy is cheaper, there is a potential of an attractive business case, especially if the elspot price can be predicted further into the future. The cold stores can provide flexibility by load shifting to the energy grid by moving their extensive energy use to off-peak hours. To fulfill the potential, it is necessary to measure some data in the cold stores to be able to control them and ensure food safety. A case study was tested and revealed that by cooling further in periods of low-cost electricity could results in 30% savings. With proper elspot price forecasting this percentage could reach up to 40%. Theoretically, by utilizing the full capacity of cold stores in Denmark for thermal energy storage, it is possible to use 2% of the average wind electricity production.
It is well known that there is a need to develop technologies to achieve thermal comfort in buildings lowering the cooling and heating demand. Research has shown that thermal energy storage (TES) is a way to do so, but also other purposes can be pursued when using TES in buildings, such as peak shaving or increase of energy efficiency in HVAC systems. This paper reviews TES in buildings using sensible, latent heat and thermochemical energy storage. Sustainable heating and cooling with TES in buildings can be achieved through passive systems in building envelopes, Phase Change Materials (PCM) in active systems, sorption systems, and seasonal storage. ; The work partially funded by the Spanish government (ENE2011-22722 and ULLE10-4E-1305). The authors would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. PIRSES-GA-2013-610692 (INNOSTORAGE). Alvaro de Gracia would like to thank Education Ministry of Chile for Grant PMI ANT1201.
The objective of the present work was to research the storage behavior of a fluidized bed filled with a granular phase change material (PCM) with a small particle diameter (d(p) = 0.54 mm). The performance of the fluidized bed was compared to that of well-known storage methods such as fluidized beds with sand and packed beds based of sand and PCM. For this purpose, heating experiments were conducted in a cylindrical bed with air as the working fluid. The influence of the bed height and flow rate on the storage and recovery efficiencies of the fluidized bed of PCM was analyzed. Additionally, the stability of the PCM during various charging-discharging cycles was studied. The results indicate that this PCM is an alternative material that can be used in fluidized bed systems to increase the efficiency of storing thermal energy in the form of latent heat. Under the experimental conditions tested in this study, higher charging efficiencies were observed for fixed and fluidized beds based on PCM than those of sand. High gas velocity and low bed height shorten the charging time but also reduce the charging efficiency. The cycling test shows that the PCM is stable under bubbling conditions up to 15 cycles, which corresponds to approximately 75 h of continuous operation. ; This work was founded partially by the Spanish Government (Project ENE2010-15403), the regional Government of Castilla-La Mancha (Project PPIC10-0055-4054) and Castilla-La Mancha University (Project GE20101662). ; Publicado
Thermal energy storage (TES) is recognised as a key technology for further deployment of renewable energy and to increase energy efficiency in our systems. Several technology roadmaps include this technology in their portfolio to achieve such objectives. In this paper, a first attempt to collect, organise and classify key performance indicators (KPI) used for TES is presented. Up to now, only KPI for TES in solar power plants (CSP) and in buildings can be found. The listed KPI are quantified in the literature and compared in this paper. This paper shows that TES can only be implemented by policy makers if more KPI are identified for more applications. Moreover, close monitoring of the achievements of the already identified KPI needs to be carried out to demonstrate the potential of TES. ; The work is partially funded by the Spanish Government (ENE2011-28269-C03-02, ENE2011-22722). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREA (2014 SGR 123) and research group DIOPMA (2014 SGR 1543). The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° PIRSES-GA-2013-610692 (INNOSTORAGE).
Existing commercial parabolic trough power plants use thermal oil as a heat transfer fluid, with working temperatures in the region of 400 °C. In order to achieve more efficient generating systems, a second generation of parabolic troughs that operate at temperatures higher than 400 °C is being developed. One possibility Abengoa Solar is assessing is the use of direct steam generation (DSG) inside parabolic troughs in order to achieve higher temperatures; in a first stage heating up to 450 °C and in a second stage heating up to 550 °C. For the future market potential of parabolic trough power plants with DSG, it is beneficial to integrate thermal energy storage (TES) systems. Different TES options based on the most known technologies, steam accumulators, molten salts (MS), and phase change materials (PCM), are presented and compared in this paper. This comparison shows as main conclusion of the study that a combined system based on PCM-MS has a clear advantage in the ratio with 6 or more equivalent hours of storage, while with lower than 6 h, steam accumulators are considered the best option. ; The work partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER)). Prof. Luisa F. Cabeza would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). This project has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under Grant agreement N°PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 657466 (INPATH-TES).
Der saisonale Versatz von Angebot und Nachfrage im Wärmesektor kann über Speicherlösungen ausgeglichen werden. Für die jahreszeitliche Speicherung von Wärme und Kälte sind Aquiferspeicher (ATES) als vielversprechende Lösung vermehrt in den Fokus gerückt. Mit derzeit jeweils nur einem betriebenen Niedrigtemperatur- (NT) und Hochtemperaturspeicher (HT) fristet die Technologie in Deutschland allerdings noch immer ein Nischendasein. Diese Studie liefert einen Überblick über die aktuelle Entwicklung der Aquiferspeicherung in Deutschland und diskutiert Stärken und Schwächen sowie Chancen und Risiken. Trotz eines großen Nutzungspotenzials wird der Markteinstieg in Deutschland durch fehlende Anreizprogramme, mangelnde Kenntnisse sowie nicht vorhandene Pilotanlagen erschwert. Die Speichertemperaturen von HT-ATES (>50°C) erhöhen dessen Nutzungsmöglichkeiten, haben aber verstärkte technische und legislative Risiken zur Folge. Eine kommerzielle ATES-Nutzung in Deutschland ist daher nur möglich durch die Anpassung genehmigungsrechtlicher Anforderungen, die Schaffung von Fördermaßnahmen, die Umsetzung von Demonstrationsanlagen und die Darlegung von deren wirtschaftlichen und ökologischen ...
AbstractChina is committed to the targets of achieving peak CO2 emissions around 2030 and realizing carbon neutrality around 2060. To realize carbon neutrality, people are seeking to replace fossil fuel with renewable energy. Thermal energy storage is the key to overcoming the intermittence and fluctuation of renewable energy utilization. In this paper, the relation between renewable energy and thermal energy storage is first addressed. Then, the classifications of thermal energy storage and Carnot batteries are given. The aim of this review is to provide an insight into the promising thermal energy storage technologies for the application of renewable energy in order to realize carbon neutrality. Three types of heat storage methods, especially latent heat storage and thermochemical heat storage, are analyzed in detail. The application of thermal energy storage is influenced by many heat storage properties, such as temperature range, heat storage capacity, cost, stability, and technical readiness. Therefore, the heat storage properties for different heat storage technologies are reviewed and compared. The advantage and challenge of different heat storage technologies and Carnot batteries for carbon neutrality processes are analyzed. Finally, the prospects of different heat storage technologies are summarized.