Electric Energy Producers Research Articles

Specific solutions for reducing energy consumption in existing and new AAC plants

AbstractThe life cycle analysis of AAC has shown that the majority of CO2 emissions is caused by the binding agents: cement and quicklime. Only 16% are generated during the production process. However, the warning of gas shortages, power black‐out scenarios and the enormous increase in energy costs are now drawing attention to implement more energy‐saving measures into the production process. Considering renewable energy sources, e.g. photovoltaic or wind power, there are legitimate concerns regarding high consumers, like the sand mill or slurry agitators and their load peak, especially when starting the machines. Before installing renewable electrical energy producers, it is essential to minimise the basic load, avoid load peaks and use existing electrical “energy producers”. Although large energy savings like autoclave steam transfer, heat recovery systems, energy saving motors, LED‐lights are already standard in most plants, a lot of energy is still wasted in the industry. This seminar will demonstrate with specific examples additional new energy saving measures like: intelligent start/stop automatic energy recovery or storage energy efficient machine design smart lighting control predictive maintenance algorithms. Each individual measure does not seem to have a big influence but it may come as a surprise how much energy saving potential there is in the sum of these individual measures. Specifically, tested and implemented energy‐saving measures in WEHRHAHN AAC plants will be explained, giving answers to: How can existing AAC plants be even more updated in an energy‐efficient manner? What does a modern, energy‐efficient AAC plant look like?

Power Losses Caused by Load Imbalance in the Central Building of PGRI Semarang University

The use of energy is basically very much needed in everyday life. Energy that is widely used is electrical energy, because electricity is one of the important factors in human life. Some electrical energy producers, in the country use fossil fuel sources such as coal and petroleum, and fossil energy is not renewable. Therefore, the government through the Regulation of the Minister of Energy and Mineral Resources number 14 of 2012 regulates energy management to control energy consumption in order to achieve effective and efficient energy utilization. PGRI Semarang University [L1] as an academic institution uses a lot of non-linear loads for administrative, teaching, laboratory and other supporting activities. Based on the analysis of data obtained at the Center Building of PGRI Semarang University experiencing an imbalance, the condition is not in accordance with the standards and risks increasing power losses. Seeing these conditions, recommendations were obtained that can be implemented at the Center Building of PGRI Semarang University, namely, balancing the load of phases R, S, T to reduce current imbalances. From the load imbalance, there were power losses on the neutral wire of 889,363 kW and power usage for one day in the R, S, T phases of 15,497,991 kW

Elastic-Plastic stress analysis in the pole fixation of an electric generator

Hydroelectric power plants are currently the most efficient large scale electric energy producers. Therefore, there are many opportunities for construction of new hydroelectric power plants throughout the world, which makes the study and design of improved electric power generators a priority. The core equipment of an electric power plant is the electric power generator, which can deliver hundreds of MW of electric power, while withstanding high levels of mechanical and thermal stresses under high rotation speeds. Therefore, the design of the electric generator, especially the rotor component, must ensure structural integrity, safety of operation, and an extended lifetime of 30–40 years. To achieve the safe and reliable operation of the generator, one of its components that must be designed after a detailed and comprehensive stress analysis is the rotor pole fixation. When the hydroelectric generator operates under high stress conditions, due to frequent start-stop cycles, structural elements such as the rotor poles fixations could operate beyond their endurance limit and could be exposed to the risk of failure. This paper presents an elastic–plastic finite element analysis of the mechanical response of the pole fixation, part of an assembly with three hammerheads of a hydroelectric generator rotor, under various loading conditions. The elastic–plastic stress analysis leads to a safe design at much higher operational loads compared to a linear elastic analysis and may be further used to study the effect of crack appearance in the plastic zone, preventing a catastrophic failure of the generator.

On the possibility of obtaining ultra-supercritical steam parameters at Nuclear Power Plants with fast neutron reactors using non-nuclear steam superheating

Nuclear and thermal power plants constitute the largest part of Russia’s power grid (about 67%). Today the world thermal power industry has already begun the transition to ultra-supercritical steam parameters, which makes it possible to increase the efficiency and reduce fuel consumption, and, accordingly, the discharge of harmful substances into the environment. Nuclear power plants (NPPs) need to increase their performance to keep up with other electric energy producers in the market. One of the ways to increase the energy efficiency of nuclear power plants with fast reactors is to improve the thermodynamic cycle. The paper presents computer-simulated steam-cycle arrangements for NPPs with a BN-1200 reactor using non-nuclear superheating of steam, as well as steam compression to obtain super-supercritical steam parameters, and an assessment of the efficiency of using these cycle arrangements.

Analysis of an application possibility of geopolymer materials as thermal backfill for underground power cable system

The circular economy is a closed cycle that allows one to reuse the industrial waste, as well as minimize the energy and resources losses during the production process. This paper presents an innovative idea of the application of a geopolymer cable backfill for underground power cable system installation. The closed cycle, in this case, is formulated as follows: the primary resource is the waste from the combustion of fossil fuels, i.e., fly ash that is utilized to form the geopolymer matrix. The geopolymer then is used as thermal backfill in underground power cable systems. Utilization of combustion by-products in the form of a geopolymer is a highly profitable solution since landfill waste disposal, in this case, generates considerable costs for the electrical energy producers. In typical applications, geopolymers are used as insulators. By adding individual components, the thermal conductivity of 2.0 W/(m K), higher than of typical thermal backfills (Fluidized Thermal Backfill), which value is close to 1.5 W/(m K), is reached. What is very important, geopolymers can absorb water better than typical sand–cement mixtures. As a result, a high thermal conductivity with the temperature increase is maintained. The application of geopolymers as thermal backfills has the potential to improve the flexibility of underground power cable systems, as well as to minimize the material costs of installation. The case study is presented to show the economic benefits of using the combustion by-products as a geopolymer thermal backfill. The finite element method model of an underground power cable system is developed, and optimization of backfill dimensions is provided to minimize the material costs using the geopolymer thermal backfill and to maximize the underground power cable system performance. The main result of this paper is that the application of geopolymers leads to a decrease in underground power cable system costs, compared to traditional backfill (sand–cement mixture). The reason is the higher value of thermal conductivity, which allows selecting a cable with a smaller cross-sectional area. Also, the environmental benefits of geopolymer application for cable bedding are discussed.Graphic abstract

Prosumer’s impact on low voltage distribution networks

The use of renewable energy, within nowadays energy policy, has increased considerably all over the world in order to respond to the increasing energy consumption and to reduce the environmental impact of the electricity generation. At the beginning, the relatively low penetration levels of distributed generation does not produce problems, however, the nowadays massive increase of local power generation have led to new integration challenges in order to ensure the reliability and quality of the power supply. This paper also highlights some aspects regarding the use of the active distribution networks of low voltage to which electric energy producers are connected-the prosumers: advantages and disadvantages for the consumer and for the supplier, technical requirements for connection, identification of the problems of power quality.

Performance of microbial fuel cell double chamber using mozzarella cheese whey substrate

Nowadays the availability of electric energy is decreasing, hence there is a need for innovation of electric energy producer alternative; one of them is microbial fuel cell (MFC). MFC is a bioelectrochemical system generated by bacterial metabolism that utilizes organic substrate. One of the substrates that can be used is whey, a waste generated from cheese production. Therefore, this study aimed to determine the power of potential current and voltage generated from the use of whey cheese as a substrate for bacterial metabolism. In this research, double chamber system was used in microbial fuel cell reactor by using cheese whey as substrate at anode and potassium permanganate as cathode and utilizing membrane nafion 212 as membrane of proton exchange. The variable of experiment was bacteria type. The types of bacteria used in this study were Lactobacillus bulgaricus, Streptococcus thermophillus and Lactobacillus casei. While the operating time used was 100 hours. The highest current produced was 74.6 μA and the highest voltage was 529.3 mV produced by Lactobacillus bulgaricus bacteria. In this study, it was also found that the death phase of the three bacteria was at 70-80 hours.

Economic Dispatch with Integrated Wind-thermal using Particle Swarm Optimization

The Economic dispatch is an important optimization task in power system. Thermal power plants are the major electrical energy producers. Need for renewable energy occurs due to the extinction of fossil fuels. Hence, it is necessary to operate these renewable plants with the thermal plants. In India, especially in Tamilnadu, Wind is the renewable plant which is widely available. The problem with the wind plant is its unpredictability.Hence, better wind thermal coordination economic dispatch method is necessary to integrate wind power reliably and efficiently. In this paper, Particle swarm optimization (PSO) technique is utilized to coordinate the wind and thermal generation dispatch and to minimize the total production cost. Ten units of thermal system incorporating wind power plant is utilized for numerical simulation. Different simulations with and without wind power production are simulated. Simulation result shows the effectiveness of wind power generation in reducing total fuel cost when compared with the genetic algorithm.

Particle Swarm Optimization for the Optimal Wind–Thermal Coordination

The Economic Dispatch is an important optimization task in power system. Thermal power plants are the major electrical energy producers. Need for renewable energy occurs due to the extinction of fossil fuels. Hence, it is necessary to operate these renewable plants with the thermal plants. In India, especially in Tamil N adu, Wind is the renewable plant which is widely available. The problem with the wind plant is its unpredictability. Hence, better wind thermal coordination economic dispatch method is necessary to integrate wind power reliably and efficiently. In this paper, Particle swarm optimization (PSO) technique is utilized to coordinate the wind and thermal generation dispatch and to minimize the total production cost. Ten units of thermal system incorporating wind power plant is utilized for numerical simulation. Different simulations with and without wind power production are simulated. Simulation result shows the effectiveness of wind power generation in reducing total fuel cost when compared with the genetic algorithm.

Insuring unit failures in electricity markets

An electric energy producer participates in futures markets in the hope of hedging the risk of trading in the pool. However, this producer is required to supply the energy associated with all its signed forward contracts even if some of its units are forced out due to unexpected failures. In this case, the producer must purchase some of the energy needed to meet its futures market commitments in the pool, which may result in high losses if the pool prices happen to be higher than the forward contract prices. To mitigate these losses, the producer can take out insurance against the forced outages of its units. Using a stochastic programming model, this paper analyzes the convenience of signing an insurance against unit failure by an electric energy producer and its impact on forward contracting decisions. Results from a realistic case study are provided and analyzed.

A two-stage stochastic programming model for electric energy producers

The bilateral contract selection and bids definition constitute a strategic issue for electric energy producers that operate in competitive markets, as the liberalized electricity ones. In this paper we propose a two-stage stochastic integer programming model for the integrated optimization of power production and trading which include a specific measure accounting for risk management. We solve the model by means of a novel enumerative solution approach that exploits the particular problem structure. Finally, we report some preliminary computational experiments.

The fuel cell yesterday, today and tomorrow

The fuel cell has some characteristics of a battery carrying out direct chemical conversion into electric energy. In relation to classical systems used for chemical energy conversion into electric power, through heat energy and mechanical operation, the fuel cell has considerably higher efficiency. The thermo-mechanical conversion of chemical into electric energy, in thermal power plants is carried out with 30% efficiency, while the efficiency of chemical conversion into electric energy, using a fuel cell is up to 60%. With the exception of the space programme, the commercial usage of the fuel cell did not exist up to 1990, when the most developed countries started extensive financial support of this source of energy. By 1995, more than a hundred fuel cells were installed in the process of electricity generation in Europe, USA and Japan, while nowadays there are thousands of installations, of efficient energetic capacity. Because of its superior characteristics, the fuel cell compared to other commercial electric energy producers, fulfills the most important condition - it does not pollute or if it does, the level is minimal. With such characteristics the fuel cell can help solve the growing conflict between the further economic development of mankind and the preservation of a clean and healthy natural environment.

Advantages of the LV100 as a Power Producer in a Hybrid Propulsion System for Future Fighting Vehicles

The core of any hybrid propulsion system is a high power density, low weight, and fuel efficient electric energy producer. The LV100 recuperated turbine engine is such a system. This engine is well suited to provide electric power efficiently at a volume and weight significantly lower than current systems. Originally designed for vehicular use and environment to drive a Hydrokinetic transmission, the turbine’s high output speed lends itself to incorporate into the engine design an advanced generating device. This LV100 engine-based electric energy producer will provide in excess of 1MW of electric power in a volume of under one cubic meter at a weight of about 2500 pounds at fuel efficiencies comparable to advanced vehicular diesel engines. Recent state-of-the-art improvements in materials and component technology will permit further reductions in volume/weight and increase the system fuel efficiency. The technologies required to reach a volume of under one cubic meter, the system performance projections obtainable by technology upgrades and the program achievements to date are discussed. [S0742-4795(00)03103-3]

The Hausdorff dimension as a tool of step-by-step prediction

Forecasts of the random processes occurring in power systems should be characterized by very high accuracy—inaccurate forecasts always cause serious economic losses for electrical energy producers and distributors. The processes of power demand, electrical energy demand, and development of power networks exhibit self-similar features. This peculiarity enables the Hausdorff dimension to be applied to formulate prediction models of the above-mentioned quantities. The models are characterized by simplicity and high accuracy. This work deals with models of step prediction of random linear and periodic functions characterized by self-similarity. The definition of the Hausdorff dimension and the principles of generating self-similar geometrical forms and formulating the prediction models for self-similar processes are presented. Examples of prediction models and their application in electrical power engineering are given. The problem of predicting power demands in state and local electrical power systems is described in detail. The reader is also provided with an annotated list of English-language papers issued in 1918–1980 concerning the prediction of power demands, as well as the most important American and Polish works of the last few years.

Relationship between desalination processes and electric energy generation

In order to evaluate energy balances in the desalination processes, two simplified models are suggested: the first one for Reverse Osmosis process; the second one for distillation processes. These models are extended all over the involved country because we cannot consider the desalting plant only. We have to put in the picture the role of the electric energy to be tranferred to or from the surrounding country which is an electric energy user and/or producer. Reverse Osmosis is an electric energy consumer. It is competitive if the cost of electric energy is low. Distillation processes heated by steam are electric energy producers because the opportunity to cogenerate steam and electric energy. They are competitive if the sale value of the electric energy is high. The electric energy cost or value related to the country to be considered, is the factor checking the winner of the contest between the two processes.

Electrical-energy producers and distributors meet

Electrical-energy producers and distributors meet