Projects / Programmes
Advanced heat storage materials for integrated storage solutions
| Code |
Science |
Field |
Subfield |
| 1.04.03 |
Natural sciences and mathematics |
Chemistry |
Inorganic chemistry |
| Code |
Science |
Field |
| P003 |
Natural sciences and mathematics |
Chemistry |
| Code |
Science |
Field |
| 1.04 |
Natural Sciences |
Chemical sciences |
porous silicates, zeolites, heat-storage materials, adsorbents, heat-storage system, heat and mass transfer, numerical modelling
Researchers (16)
Organisations (4)
Abstract
Thermal energy storage is recognized as one of the crucial technologies for enabling more efficient use of fossil fuels and renewable energies by providing the supply-demand balance. In this context, thermochemical heat storage (TCS), which utilise the reversible chemical and physical sorption of gases, mostly water vapour, in solids, is considered as the only storage concept with a potential for long-term, also seasonal, low-temperature heat storage (up to 150 oC) of high enough storage density to be also economically attractive. Under the influence of a heat supply in TCS, water is desorbed from the material that is then stored separately (an endothermic phenomenon referred to as the charging or activation of material). When water vapour and sorbent are put into contact, there is a heat release (an exothermic phenomenon referred to as a material’s discharge or deactivation). The TCS has the potential to make extensive use of a solar thermal energy and low temperature residual heat from industry, thus leading to a low carbon energy society. The essential breakthrough, which is still necessary for commercialization of sorption heat storage systems is to optimize the storage material to achieve a high energy density in the storage tank in the conditions (Dp, DT), which can be generated in the system. Namely, despite the fact that some materials show remarkable results for heat storage in the laboratory testing regarding the maximum storage density (our material with a density of 240 kWh/m3 is one of the best in the world), the dynamics of the process is in most of the known cases inadequate for effective use. Therefore, the aim of proposed project is to move the development of sorption heat storage systems to a higher level with the design, optimization and scale-up of materials by considering also the dynamics of the process in the particular storage design (numerically and experimentally) and, consequently, redefine requirements concerning their properties. The development will be focused on systems, which utilize low-temperature solar energy. The materials proposed are porous aluminosilicates with lower aluminium content prepared by controled dealumination procedures with or without further treatment with inorganic salts for optimal extra-framework metals' distribution. The development of new sorbents with exactly controlled chemical composition and structural properties will be based on energy-efficient, safe and environmentally friendly production of materials. The proposed "bottom-up" approach of materials engineering, both at the molecular level as well as the system/heat storage tank, will be realized by aligned action of scientists and experts in various fields. The results of the proposed work are expected to trigger further research in the innovative synthesis procedures of porous materials and in the use/testing of new materials in other applications, i.e. aside from long-term storage for solar energy, large impact is expected to be found in load shifting applications (for heat pumps and poly-generation systems) within the context of smart energy infrastructures. The expected impacts beyond the project are investments in material production facilities and in system manufacturing as well as activities in systems maintenance.
Significance for science
The proposed project approach is expected to have great impact on renewable heat technology and on the efficiency of the existing heating technologies. The first scientific outcome of this project will be a better understanding of the realatons between material synthesis procedures, structural properties and macroscopic properties that are important for thermal energy storage, which still represent a bottleneck in the TCS development. This will result from a proposed work plan including a circuit: synthesis, structural characterization, storage performance characterization and process and system modelling. Specific questions concerning to the role of porosity, specific surface and chemical composition on water mass and heat transfer, and the influence of the synthesis procedure on the quality of inorganic cations dispersion in the porous matrix, will be addressed.
These tasks will be framed by targeted objectives that are oriented by the application (the focus on solar heat storage). Furthermore, the result of the project will be optimized materials or/and optimized procedure that takes into account the global cost effectiveness.
The collaboration between partners from different research groups with long expertise will lead to future common synergies trying to obtain new innovative solutions. The consortium will be able to carry out the project through its access to state-of-the-art experimental and computational facilities, and the industrial partners will know how to bring selected material into the market. The project objectives are related to Slovenian and EU energy roadmaps.
Significance for the country
The proposed research within the project will be performed in energy-related and environmental areas, which have recently attracted world-wide attention. An effective heat storage is one of the primary research focuses in Slovenia and Europe, as it is crucial for the wider use of solar thermal energy and waste heat for heating, cooling and hot water preparation. The share of energy used in EU-27 households for heating purposes only is between 40% (Southern Europe) and 80% (Northern Europe), of which more than 75% is still covered using conventional fossil fuels such as coal, oil or natural gas. In Slovenian households more than 65% of final energy demand in recent years was for space heating and additional 15% for domestic hot water. After the entry into force of the Nearly Zero Energy Building (NZEB) concept in 2020, close to passive buildings will become the standard in a lot of European countries so that the total market is expected to rise up to 1 000 000 housing units. The concept of NZEB also includes the requirement of use of local renewable energy which strengthens position of the seasonal storage technology. The storage materials needs are evaluated to up to 2 800 000 tons/year. The same rise is expected from the system manufacturing and maintenance activities. On the other hand, an accelerated market deployment of solar thermal systems with TCS in EU is expected to lead to primary energy savings from fosil fuels to 400 TWh per year by 2030, resulting in a significant reduction of greenhouse gas emissions.
The scientific outcomes are expected to have a significal economic impact; they will make possible the development of industrial activities in the field of storage materials production and reduce investment risks. With other words, focus on materials performances, raw materials and production costs should make these materials competitive enough to be used in seasonal storage systems. In this way, our industrial partner can improve competitiveness through innovative products on the domestic and foreign markets. The optimised materials will also boost further R&D activities in heat storage systems conception in the fortcomming years.
Most important scientific results
Final report
Most important socioeconomically and culturally relevant results
Interim report,
final report
