The Potential of Ecological Distributed Energy Generation Systems, Situation, and Perspective for Poland

Poland needs to fulfill its climate goals and become “climate neutral” by 2050. The plan is intricate for the Polish Government because coal-powered power plants generate about 80 percent of electricity in the country. Although policymakers are making an effort to redesign the energy sector, a lot still remains to be done. The viral trend in that transformation involves installing photovoltaic (PV) panels by private, corporate, and self-government investors. For example, the “My energy” support program of the National Fund for Environmental Protection and Water Management has helped finance 220,000 micro-PV installations. The achievement is significant but constitutes only partial success. PV powerplants will not simply replace coal powerplants. That is why the research on the ecological distributed energy generation systems has to be executed. The article presents the research results on ecological distributed energy generation systems, making the transformation of the Polish energy sector possible. The study’s primary objectives were to review the energy situation with particular attention paid to the technologies that could be used as the ecological distributed energy generation systems and draw the scenarios for the sector development. The authors used Desk research, the Delphi method supported with the Computer Assisted-Web Interview (CAWI) technique, and the Weighted SWOT analysis to fulfill the objectives. The findings showed that photovoltaic (PV) systems would be the fastest-growing energy sector even in the perspective of doubling the energy consumption by 2050. Private investors investing in ecological distributed energy generation systems, especially the PV systems mentioned above, and biomass or biogas systems, would significantly help policymakers, including those in Poland, fulfill the climate goals.

Combining Value-Focused Thinking and PROMETHEE Techniques for Selecting a Portfolio of Distributed Energy Generation Projects in the Brazilian Electricity Sector

This article aims to propose a multi-criteria model to support decision-making from a portfolio in selecting technologies for Distributed Generation of Energy (DGE) projects based on the characteristics of the geographic space in Brazil. The decision model involves using multi-criteria to support the evaluation, prioritization, and selection of projects under a multistage decision-making process that fits into a strategic management cycle within the energy sector of Mato Grosso do Sul (Brazil). The over-classification techniques Preference Ranking Organization Technique for Enrichment Evaluations (PROMETHEE) II and V were applied under the Value-Focused Thinking (VFT) approach, reflecting the decision-maker or manager preferences among several conflicting criteria in the investment context of sustainable distributed energy generation projects. Based on real data, a numerical application is employed to view the steps of this decision model and illustrate the adequacy and effectiveness in practical issues of portfolio management.

Synthesis of scheme-cycle designs of absorption water-ammonia thermotransformers with extended degazation zone

The search for new and improvement of existing technical design of energy converter systems for specific consumers requires a reasonable choice of the most rational design for these objects. Thermotransformers that operate on the reverse and mixed thermodynamic cycles, in combination with power plants utilizing renewable and non-traditional primary energy (fuel), are considered to be of interest for small-scale power generation (trigeneration systems), which is consistent with the concept of distributed energy generation. Cold in trigeneration systems is provided by heat-using thermotransformers. This paper reports a method for synthesizing a scheme-cycle designs of absorption water-ammonia thermotransformers that utilize renewable heat sources with a low-temperature potential of 90–250 °С. A "cycle method" was applied to perform the thermodynamic analysis of the cycle of simple absorption thermotransformers with the expansion of the degazation zone with an increase in the temperature of the heating source; the technological schemes for the corresponding cycles have been substantiated. The influence of changing the degazation zone on the energy efficiency of the machine has been established. A scheme-cycle designs of the thermochemical compressor for a thermotransformer with a return supply of solutions to the generator and absorber at " excess temperatures" has been proposed, as a way to improve the cycle energy efficiency. A comparative analysis of the degree of thermodynamic perfection of the considered cycles has been performed using a specific example. The thermodynamic analysis demonstrated that the practical implementation of the scheme-cycle designs "with excess temperatures" could provide energy-saving conditions in small-scale trigeneration systems.

Electrical Energy Flow Algorithm for Household, Street and Battery Charging in Smart Street Development

The world demands a smart and green future in every sector, which directly corresponds to increases in electrical energy demand one way or another. It is unfeasible to attain future energy demand with the present electrical infrastructure. That means more research and development is required. Future energy sources should be intermittent, and, in addition, the energy sector should be more inwards for distributed energy generation with demand side control. In such cases, the smartest and most autonomous system would be essential to deliver an adequate power supply with all electrical properties. A real-time monitoring and control system with a self-healing infrastructure is a forthcoming desideratum. By accepting these challenges, we have designed a smart street. The basic idea of the smart street is presented in this paper as a landing page; the paper is more focused on emphasizing information regarding the electrical energy flow algorithm for the household, street, and street battery storages. This algorithm is helpful for two-way energy flow and the automatic detection of islanding and the grid connection mode. It will be not only helpful for the users but to the utility as well.

The performance analysis of type-2 fuzzy fractional-order tilt integral derivative controller with enhanced Harris hawks optimization

Modern Alternating Current (AC) microgrids (ACMGs) are highly complex because of the indeterminate nature of distributed energy generation and load causes frequency fluctuations. It is essential to maintain the constant power amongst load and generations by the proper design of an efficient controller to stabilize frequency fluctuations. In this paper, the type-2 fuzzy fractional-order tilt integral derivative controller structure is designed and analyzed for frequency control of an ACMG by using an enhanced Harris hawks optimization (EHHO). The modified optimization technique is analyzed employing test functions and compared with similar methods. It is noticed that the modified optimization technique is outperforming the other methods in most of the test functions. The frequency control performance of an ACMG is demonstrated and compared with the original Harris hawks optimization (HHO) and other optimization methods. The proposed type-2 fuzzy fractional-order tilt integral derivative controller tuned with EHHO technique is demonstrated to be effective and superior to any of the alternatives by application to a typical two-area test system.

Laboratory Evaluation of a Phasor-Based Islanding Detection Method

Constantly growing distributed energy generation based on renewable sources creates a number of new challenges for electrical power system operation. One of the challenges is islanding detection. Unintentional islanding, which can cause health and safety hazards for the personnel, is currently being experienced by a growing number of consumers/prosumers especially in the case of photovoltaic inverters. This work presents a new islanding detection method based on synchrophasor measurements. The proposed method works in either a passive or hybrid mode. In a passive mode, a single phasor measurement unit (PMU) in the island region is used. In a hybrid mode, one PMU in the island and another one outside the island are exploited. The proposed method was verified in conducted laboratory tests that confirmed the applicability of PMUs data for effective detection and monitoring of unintentional islanding.

Cyber Attacks in Transactive Energy Market-Based Microgrid Systems

Due to the increasing integration of distributed energy generation in the electric grid, transactive energy markets (TEMs) have recently emerged to balance the demand and supply dynamically across the grid. TEM enables peer to peer (P2P) energy trading and brings flexibility by reducing users’ demand in the grid. It also enhances the system’s efficiency and reduces the pressure on electricity networks. However, it is vulnerable to major cyber attacks as users equipped with smart devices are participating autonomously in the energy market, and an extensive amount of information is exchanged through the communication channel. The potential attacks and impacts of those attacks need to be investigated to develop an attack resilient TEM-based power system. Hence, in this paper, our goal is to systematically identify possible cyber attacks associated with a TEM-based power system. In order to achieve this goal, we classify the attacks during the P2P and flexibility schemes of TEM into three main categories. Then, we explore the attacks under each category in detail. We further distinguish the adversary roles of each particular attack and see what benefits will be received by an adversary through each specific attack. Finally, we present the impact of the attacks on the market operation, consumers, and prosumers of the TEM in this paper.