Technical University of Cluj-Napoca

About: Technical University of Cluj-Napoca is a education organization based out in Cluj-Napoca, Romania. It is known for research contribution in the topics: Robot & Control theory. The organization has 4186 authors who have published 8436 publications receiving 53588 citations. The organization is also known as: Universitatea Tehnică din Cluj-Napoca.

Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids

Abstract: In this paper, we investigate the use of decentralized blockchain mechanisms for delivering transparent, secure, reliable, and timely energy flexibility, under the form of adaptation of energy demand profiles of Distributed Energy Prosumers, to all the stakeholders involved in the flexibility markets (Distribution System Operators primarily, retailers, aggregators, etc.). In our approach, a blockchain based distributed ledger stores in a tamper proof manner the energy prosumption information collected from Internet of Things smart metering devices, while self-enforcing smart contracts programmatically define the expected energy flexibility at the level of each prosumer, the associated rewards or penalties, and the rules for balancing the energy demand with the energy production at grid level. Consensus based validation will be used for demand response programs validation and to activate the appropriate financial settlement for the flexibility providers. The approach was validated using a prototype implemented in an Ethereum platform using energy consumption and production traces of several buildings from literature data sets. The results show that our blockchain based distributed demand side management can be used for matching energy demand and production at smart grid level, the demand response signal being followed with high accuracy, while the amount of energy flexibility needed for convergence is reduced.

Electric vehicle battery technologies: From present state to future systems

Abstract: Electric and hybrid vehicles are associated with green technologies and a reduction in greenhouse emissions due to their low emissions of greenhouse gases and fuel-economic benefits over gasoline and diesel vehicles. Recent analyses show nevertheless that electric vehicles contribute to the increase in greenhouse emissions through their excessive need for power sources, particularly in countries with limited availability of renewable energy sources, and result in a net contribution and increase in greenhouse emissions across the European continent. The chemical and electronic components of car batteries and their waste management require also a major investment and development of recycling technologies, to limit the dispersion of electric waste materials in the environment. With an increase in fabrication and consumption of battery technologies and multiplied production of electric vehicles worldwide in recent years, a full review of the cradle-to-grave characteristics of the battery units in electric vehicles and hybrid cars is important. The inherent materials and chemicals for production and the resulting effect on waste-management policies across the European Union are therefore reported here for the scope of updating legislations in context with the rapidly growing sales of electric and hybrid vehicles across the continent. This study provides a cradle-to-grave analysis of the emerging technologies in the transport sector, with an assessment of green chemistries as novel green energy sources for the electric vehicle and microelectronics portable energy landscape. Additionally, this work envisions and surveys the future development of biological systems for energy production, in the view of biobatteries. This work is of critical importance to legislative groups in the European Union for evaluating the life-cycle impact of electric and hybrid vehicle batteries on the environment and for establishing new legislations in context with waste handling of electric and hybrid vehicles and sustain new innovations in the field of sustainable portable energy.

Control and Performance Evaluation of a Flywheel Energy-Storage System Associated to a Variable-Speed Wind Generator

Abstract: The flywheel energy-storage systems (FESSs) are suitable for improving the quality of the electric power delivered by the wind generators and for helping these generators to contribute to the ancillary services. Supervisors must be used for controlling the power flow from a variable-speed wind generator (VSWG) to the power grid or to an isolated load. This paper investigates the control method and the energetic performances of a low-speed FESS with a classical squirrel-cage induction machine in the view of its association to a VSWG. A test bench is developed, and experimental results are presented and discussed