Numerical comparison and sizing of sensible and latent thermal energy storage for compressed air energy storage

Kaya, Mine
Intermittent and variable characteristics of renewable energy systems can be compensated by energy storage systems (ESS). There is a wide range of ESS specialized for different applications. Compressed Air Energy Storage (CAES) is often used for wind power plants due to high power rating at the discharge and long discharge duration. CAES takes ambient air and pressurizes through a compressor and stores compressed air in a volume when supplied energy is greater than demand. If demand exceeds supply, CAES is discharged by drawing compressed air from storage, running turbine after heating compressed air by external heat source (fuel). Thermal Energy Storage (TES) is another ESS, which is generally coupled with solar thermal energy systems. TES systems can store sensible or latent heat in a storage medium. A feature of TES is capability of being used with CAES. External heat source can be eliminated by TES by storing thermal energy of air at the compressor exhaust to be used to heat air before turbine. CAES with TES systems are named as Adiabatic CAES (A-CAES) and comprise of a compressor, TES, air storage and a turbine. In this study, TES of an A-CAES system is modeled and effect of TES on CAES is investigated. Performance of individual TES is analyzed for different heat storage mediums - latent and sensible -, tank and heat storage medium dimensions. Aim of the present study is to model a TES, which is capable of storing maximum heat in a minimum volume and shortest duration and implement the promising designs to CAES and investigate the performance of overall system by means of efficiency and total work output using MATLAB.


Kaya, Mine; Tarı, İlker; Baker, Derek Keıth (2016-11-17)
Compressed Air Energy Storage is a promising large-scale storage system in part because of its high power rating during discharge. But it is not the cleanest way of storing energy due to the necessity of an external heat source (typically the combustion of natural gas) to heat the air at the turbine inlet. This problem can be overcome with Thermal Energy Storage by storing the thermal energy of air at the compressor exhaust in order to be used for heating air before turbine. In this study, a numerical trans...
Exergetic optimization of generated electric power split in a heat pump coupled poly-generation system
Kilkis, Birol I.; Kılkış, Şiir (2007-01-01)
This study analyzes environmental, energy, and economical benefits of a ground source heat pump, coupled poly-generation system by incorporating exergy into the energy efficiency analysis. Two additional terms, namely the rational exergy efficiency and the coefficient of performance were introduced to the primary energy savings equation in the European Union Directive 2004/8/EC. Based on the new equation, an optimization algorithm was developed, which can quantify the environmental, energy and economy benef...
Numerical investigation of a stand alone solar hydrogen energy system effects of PEFC degradation
Ender, Ozden; Tarı, İlker (null; 2015-08-12)
An existing stand-alone solar energy system producing hydrogen for energy storage is numerically investigated focusing on the degradation of Polymer Electrolyte Fuel Cell (PEFC) and its effects on the overall performance of the system. The system consists of Photovoltaic (PV) panels, polymer electrolyte based electrolyzers, H2 and O2 storage tanks and a commercial PEFC stack. A PEFC is numerically investigated both as new and as degraded (for about two years). Using a variety of observed degradation pattern...
Experimental analysis of energy storage device using phase change material integrated with a milk storage system
Nıma, Bonyadı; Somek, Suleyman Kazım; C Cıhan, Ozalevlı; Baker, Derek Keıth; Tarı, İlker (null; 2015-08-12)
Phase change materials (PCMs) have the advantage of storing latent heat at constant temperature and can possess higher energy storage densities in comparison to materials storing sensible heat. Due to these features, latent heat Thermal Energy Storage (TES) devices using PCMs are widely used to store heat in thermal systems. The aim of this study is to experimentally investigate the performance of water PCM in an improved milk storage cooling cycle integrated with a TES device. In this prototype, water is u...
Development of a methodology for sizing and assessment of wind integrated advanced adiabatic compressed air energy storage system (aa-caes)
Taştankaya, Koray; Tarı, İlker; Baker, Derek Keıth; Department of Mechanical Engineering (2014)
Renewable energy usage has become widespread and gained world-wide importance lately. In order to get high quality power from renewable energy sources to the grid, bulk energy storage system will be required as a buffer, due to the intermittent nature of renewable energy. Advanced adiabatic compressed air energy storage (AA-CAES) technology is uniquely different from conventional energy storage techniques for renewable energy in that it captures and stores the heat generated during the compression cycle and...
Citation Formats
M. Kaya, “Numerical comparison and sizing of sensible and latent thermal energy storage for compressed air energy storage,” M.S. - Master of Science, Middle East Technical University, 2015.