Cryptocurrency mining as a novel virtual energy storage system in islanded and grid-connected microgrids

Recently, significant development has occurred in the field of microgrid and renewable energy systems (RESs). Integrating microgrids and renewable energy sources facilitates a sustainable energy future. This paper proposes a control algorithm and an optimal energy management system (EMS) for a grid-connected microgrid to minimize its operating cost. The microgrid includes photovoltaic (PV), wind turbine (WT), and energy storage systems (ESS). The interior search algorithm (ISA) optimization technique determines the optimal hour-by-hour scheduling for the microgrid system, while it meets the required load demand based on 24-h ahead forecast data. The control system consists of three stages: EMS, supervisory control and local control. EMS is responsible for providing the control system with the optimum day-ahead scheduling power flow between the microgrid (MG) sources, batteries, loads and the main grid based on an economic analysis. The supervisory control stage is responsible for compensating the mismatch between the scheduled power and the real microgrid power. In addition, this paper presents the local control design to regulate the local power, current and DC voltage of the microgrid. For verification, the proposed model was applied on a real case study in Oshawa (Ontario, Canada) with various load conditions.

Impact of energy storage system and distributed energy resources on bidding strategy of micro-grid in deregulated environment

Tri-level expansion planning for transmission, energy storage, and renewable energy considering carbon emission limitation

A microgrid (MG) is a discrete energy system consisting of an interconnection of distributed energy sources and loads capable of operating in parallel with or independently from the main power grid. The microgrid concept integrated with renewable energy generation and energy storage systems has gained significant interest recently, triggered by increasing demand for clean, efficient, secure, reliable and sustainable heat and electricity. However, the concept of efficient integration of energy storage systems faces many challenges (e.g., charging, discharging, safety, size, cost, reliability and overall management). Additionally, proper implementation and justification of these technologies in MGs cannot be done without energy management systems, which control various aspects of power management and operation of energy storage systems in microgrids. This review discusses different energy storage technologies that can have high penetration and integration in microgrids. Moreover, their working operations and characteristics are discussed. An overview of the controls of energy management systems for microgrids with distributed energy storage systems is also included in the scope of this review.

The planning and design of multi-energy complementary energy system is the primary key technology to ensure its safe, economic and reliable operation. Since the multi-energy complementary micro-grid contains various energy sources such as heat source and power source, and various types of energy-using loads such as heat load and electric load, the source, network and load have strong coupling relationship, and the renewable energy sources such as solar and wind have strong volatility, and the system operation scenarios are complex and diverse, it is difficult to apply the conventional planning methods directly. Therefore, in this paper, we propose a multi-energy complementary micro-grid planning method that considers the coordinated interaction of source, load and storage in detail, fully accounts for the uncertainties on the source and load sides and the coordinated coordination of multiple energy flows, establishes a user-side demand response model, which fully considers the operational constraints of interruptible load, transferable load and user satisfaction; proposes a dual-layer planning method, and proposes a black-box time-consuming solution method for the solution of the dual-layer optimization model, which effectively ensures the rapid solution to obtain the planning capacity of renewable energy sources, cogeneration units, thermal and electrical energy storage systems and other devices.

The growing share of renewable energies needs more flexible services to balance their intermittency and variance. The existing coal fired units and electrical energy storage (EES) systems may play an important role in delivering flexible services. The value of their flexibility services, along with the value of renewable energies, has to be analyzed from the perspective of the power system, in which the capacity costs and operation costs of renewable energy power units, EES systems, and thermal power generation units have to be taken into consideration. An optimal model is built to analyze the renewable energy integration and the flexibility services delivered by the EES systems and thermal power units in a power system. Taking the existing thermal power units and EES systems in North China Power Grid as an instance, the overall cost of the grid is examined for the penetration of renewable energies and flexible service provision. The results show that the growing shares of renewable energies are affected by their capacity credits and flexibility sources in the grid, and that the potential of thermal power units to provide flexible services will be reduced due to the replacement of renewable energies for thermal power generation. The results also indicate that the thermal units may be dispatched to have priority to delivering flexible services for the renewable energy integration, and that the curtailment of renewable energies may be regarded as one type of flexible service. According to these results, policy and strategy recommendations are put forward to weigh the role of existing coal-fired units and EES systems in providing flexible services, and to improve their compensation mechanism and their coordination.

Role of optimal sized dual energy storage based microgrid for ancillary service support to utility grid

An increase in the installed capacity of renewable energy sources in power system may lead to frequency deviation problems due to their intermittent nature and subsequent mismatch between generation and demand. Therefore, new components should be used to provide frequency regulation, and thus assure stable frequency. One of the solutions is the integration of energy storage systems and flexible loads. This paper investigates the dynamic influence and performance of thermostatically controlled electric water heaters and battery energy storage systems for frequency regulation in an interconnected two-area power system with high penetration of variable renewable energy generation.

The evaluation of renewable energy policies across EU countries and US states: An econometric approach

The paper made an extensive analysis of power generation in the territory of the Republic of Crimea. A special issue is the use of renewable energy sources (RES), in particular wind (WPP) and solar power plants (SPP). The current power generation capacities of the republic are determined and the power deficit is shown, which is currently covered by the electricity of the energy system of the Krasnodar Territory. One of the most important features of the development of the modern world is the increased attention of the world community to the problems of rationality and efficiency in the use of energy resources, the introduction of energy saving technologies and the search for renewable energy sources. In 2021, the countries of the Middle East and Europe increased the capacity of wind and solar power plants several times over. In India, installed renewable energy capacity has exceeded 100 GW. In June-July 2021, solar power generation in the European Union reached a record level and amounted to 39 TWh, an increase of 28%. For most European countries, renewable energy accounts for more than 15% of electricity generation in general. This is due to the fact that in the main markets, renewable, in particular solar electricity, is significantly cheaper than the energy of gas and diesel power plants.For Russia, the southern districts and coastal zones are effective geographical areas for the use of WPPs and SPPs. Thus, the Republic of Crimea is a geographically favorable place for the development of alternative energy.The technical and economic characteristics of SPP and WPP are determined, the current own wind and solar generation is considered in detail. The ways of development and permissible capacities of renewable energy sources in the Crimea are determined. According to the requirements for the systems of regulation, control and protection of renewable energy sources (RES) during their operation as part of the Unified Energy System of Russia, the use of alternative sources of electricity together with the main grid is permissible with their total capacity equal to 20% of the maximum load of the region. Therefore, the development and distribution of renewable energy in the Crimea has a huge potential. The applied systems for integrating RES into the overall energy system are considered, their shortcomings are identified.For the further development of RES in the Crimea, it is proposed to use a model of intelligent integration of SPPs and WPPs into the energy system of the peninsula using solid-state transformers. The use of power transformers for the transmission of electricity from RES to the network significantly reduces the flexibility of the system and eliminates the control of energy parameters. To increase the control capabilities of the output power to the network, as well as to reduce energy costs during voltage transformation, it is proposed to use solid-state transformers (SST) at the inverting stage. The use of SST changes the general principle of power transfer from RES to the network to the following: the DC voltage accumulated in the batteries of WPP and SPP is fed through a high-frequency inverter to a pulse transformer, where it rises to the voltage of the power line. Then it is rectified and inverted to the required mains frequency. Modern power semiconductor components may well provide such a model for integrating RES into the grid. The proposed model is distinguished by the presence of effective control of energy parameters, as well as high efficiency.

Large scale electrical energy storage systems in India- current status and future prospects

Batteries or silos: Optimizing storage capacity in direct air capture plants to maximize renewable energy use

Benefits of transmission switching and energy storage in power systems with high renewable energy penetration

Renewable energy sources are widely acknowledged as the optimal substitutes for conventional energy outlets globally. Countries are endowed with diverse renewable resources, including solar, wind, biomass, hydro, and tidal energy. Despite this abundance, there exists a substantial disparity between the demand and supply of electrical energy, with numerous regions still facing insufficient access to power. The integration of various renewable energy sources in remote and isolated locations forms a Microgrid (MG), catering adequately to local energy requirements. These microgrids have the capability to function seamlessly alongside conventional grids. Hybrid MG system, incorporating Photovoltaic (PV) with battery storage and a Wind Turbine (WT), emerges as a practical solution for electrifying remote areas in islanded mode. The WT’s installed capacity is chosen to meet critical load requirements during periods of non-availability of renewable sources. The battery's capacity is selected to cover the transition period between renewable sources or as a backup source, ensuring cost-effectiveness over WTs. The application of Adaptive Particle Swarm Optimization (APSO) has demonstrated favorable outcomes compared to existing PSO algorithms, enhancing control efficiency. In a grid-connected MG system, the integration of distributed PV generation has notably improved the voltage profile, reducing overall losses. Consequently, the presented MG systems provide both technically and economically viable solutions for ensuringcontinuous electricity supply in isolated and grid-connected systems. This approach not only mitigates pollution but also allows for the possibility of capacity addition, fostering sustainable growth in these regions.

Energy management and operational planning of renewable energy resources-based microgrid with energy saving