Hourly Price-Based Demand Response for Optimal Scheduling of Integrated Gas and Power Networks Considering Compressed Air Energy Storage

Gas-fired plants are becoming an optimal and practical choice for power generation in electricity grids due to high efficiency and less emissions. Such plants with fast start-up capability and high ramp rate are flexible in response to stochastic load variations. Meanwhile, gas system constraints affect the flexibility and participation of such units in the energy market. Compressed air energy storage (CAES) as a flexible source with high ramp rate can be an alternative solution to reduce the impact of gas system constraints on the operation cost of a power system. In addition, demand response (DR) programs are expressed as practical approaches to overcome peak-demand challenges. This study introduces a stochastic unit commitment scheme for coordinated operation of gas and power systems with CAES technology as well as application of an hourly price-based DR. The introduced model is performed on a six-bus system with a six-node gas system to verify the satisfactory performance of the model

Evaluation of Peak Shifting and Energy Saving Potential of Ice Storage Based Air Conditioning Systems in Iran

Thermal energy storage (TES) system has been introduced as a practical facility for shifting load from peak hours to off-peak hours. Because of different energy consumption during day and night, peak and off peak period is created on load curve. Ice storage technology which is a kind of TES system, is implemented in different points of the world with the purpose of solving load shifting problem. The basic process of this technology is storing energy in the ice during off-peak hours, utilizing an air conditioning unit in which the stored energy will be utilized during day. Utilization of ice storage system is a good solution for optimizing consumption of gas and electrical energy, which will be effective in urban pollution reduction. This paper aims to introduce load shifting problem and the implemented procedures to overcome this problem from the past, analyzing ice storage system as a solution to this problem. Moreover, feasibility of the ice storage technology on a case study in Iran is discussed to show the performance and efficiency of the technology. The obtained results for the case study show that by utilizing ice storage system the consumption and the paid cost will be reduced with respect to conventional system

Optimal generation scheduling of large-scale multi-zone combined heat and power systems

Combined heat and power (CHP) technology can simultaneously satisfy heat and power loads. The objective of optimal production scheduling of CHP plants is finding optimal schedule of heat and power plants according to the constraints of network and component. In this research, the solution of CHP economic dispatch (CHPED) in large scale is investigated considering different scenarios. Firstly, the CHPED is tested on a 48-unit system to obtain minimum total operation cost, which includes the operation cost of thermal plants, CHP units and boilers, and the obtained optimal solutions are compared with recent publications. Then, a novel framework for a large-scale multi-zone CHPED problem is introduced, where each zone is responsible of providing the associated heat load. Finally, the multi-objective CHP dispatch problem is studied for handling two competing objectives consisting of operation cost and emissions of pollutant gases. The emission of pollutant gases includes the greenhouse gases emitted by thermal plants, CHP units and boilers. The model is tested on a three-zone 48-unit system for verifying the performance and effectiveness of the model. An annual cost saving of $1,939,534.08 can be attained by using the applied method for the 48-unit CHP system in comparison with the reported results in recent studies