Types Of Prime Movers Research Articles

Multi-criteria evaluation of poly-generation system applied to commercial buildings with various prime movers and building types

The present study evaluates the performance of a poly-generation system applied to commercial buildings. An internal combustion engine (ICE) and solid oxide fuel cell (SOFC) used as prime movers represent different efficiency distributions according to part load ratio variation. Accordingly, discrete results are found in terms of energy, environment, and economy depending on the prime mover type applied to each building. A renewable energy system is combined with the poly-generation system, and the outputs produced from the energy generation units are transferred to the energy storage system and supplied to the demand sources. Through the parametric study and hybrid control method, the stored energy is optimally distributed to the cooling and heating system to maximize the primary energy saving ratio. The major components constituting the poly-generation system are modeled and validated based on experiments and literature to enhance the reliability of the dynamic simulation model. The monthly amounts of replenished and wasted energy are examined, and the magnitude of produced energy contribution to the building self-sufficiency ratio is also identified. When ICE- and SOFC-based poly-generations are applied to the hospital, 30.2% and 45.2% of the primary energy consumption is saved, respectively, compared with the conventional system. For the office, the corresponding systems reduce primary energy consumption by 1.8% and 37.2%, respectively. The economic feasibility of the poly-generation systems is examined considering the current energy project in South Korea.

(Digital Presentation) Fuel Cell and Battery Technologies for a 800kW Ferry: Two Optimized Scenarios

Many countries have set official targets to 100% phase out sales or registrations of new internal combustion engines (ICE) that use gasoline. Battery and fuel cell technologies have been suggested to be the best alternative for the current ICEs to be utilized in cars, buses, trucks, and boats. Although there have been studies to consider fuel cells and batteries for the cars, there are limited number of studies to consider these technologies for ferries. Different types of prime movers have been utilized to run the boats, however, most of the studies in the field are related to either the usage of fuel cell or battery as the prime mover of the boats, while the integrated system can improve the low range of batteries by maintaining high acceleration and fast re-fueling time.Two well-known types of industrial Li-Ion batteries in the market are Nickel Manganese Cobalt (NMC), and Lithium Titanite Oxide (LTO). Among the existing Li-Ion batteries in the market, LTO enjoys from the highest performance, lifespan, and safety by higher costs, whereas NMC provides acceptable performance with low costs and high specific energy. In comparison to the batteries, proton exchange membrane fuel cells (PEMFCs) have faster refueling time and higher ranges, hence the integration of batteries and fuel cells can provide the needs of ferries.In this study, the possibility of integrating the fuel cell technology and the battery is evaluated to provide 800kW electricity. PEMFC modules are integrated with a Li-Ion battery to have high ranges and efficiencies in fast refueling times for ferry applications. An optimization model was developed using the open source Julia programming language to determine the best combination of the batteries and fuel cells considering the size, weight, hydrogen consumption, and overall efficiency as the output parameters. The dynamic model captures the characteristics of the system by the changes in time and considers the impacts of batteries’ charging/discharging status on the overall performance. Two different novel scenarios are suggested to provide 800kW power for a ferry with a total length of 50.8m to transport 780 passengers considering the Lausanne-Evian round trip, which is 24km, in 70 mins. LTO and NMC type Li-Ion batteries are selected for these two different scenarios while PEMFC is the selected type of fuel cell for this ferry.Dynamic models have been developed in the MATLAB software for both the battery and fuel cell modules. Based on the presented flowchart in Fig. 1, a quasi-static optimization model has been utilized for the power split. Results indicate that the total size, and hydrogen consumption of around 8 , and 36.1 kg/h, respectively, are needed in the first scenario to reach the maximum power of 800kW with 49.5% overall efficiency. The operating power of the integrated battery and fuel cell system is between 80kW to 720 kW, which is 10% to 90% of the maximum power. In the second scenario, the corresponding values of the size, and hydrogen consumption are around 8.23 , and 36 kg/h to reach the same power by the overall efficiency of 49.6%. The first scenario uses 8 modules of PEMFCs and one module of NMC while the second scenario uses LTO as the battery with the same number of PEMFCs. Fig. 2 also shows the transient performance characteristics of the integrated system in the first scenario considering the output power and the hydrogen consumption of the fuel cells, in addition to the output energy and the state of charge of the batteries. Figure 1

Increasing the Efficiency of OEC with Use of Principle of Superposition and Thereby Increase Share of Wave Energy in Renewable Energy Resources

The quest for new renewable resources is at pinnacle in recent times. We have majorly 3 approaches Viz. [1] Finding new type of renewable resource. [2]Increase the use of already available renewable resources. [3] Increase the efficiency of prime movers so as to increase net power output by available quantity of renewable resources. This paper throws the light on unique idea of integrating the principle of superposition of waves and WEC. WEC or Wave Energy Convertor is a type of prime mover which was devised by OCEANLINX based in Australia. It basically works on compression of air column due to water column. The main drawback of wave energy is that it cannot be used in areas where waves are short and possess less energy. The new idea projected in this paper mainly addresses this issue and thus imparting the power to nations whose geographical location offers them generally short waves. Now they can also generate green energy and thus pushing world towards achieving goals of sustainable development.

Cogeneration Supporting the Energy Transition in the Italian Ceramic Tile Industry

Ceramic tile production is an industrial process where energy efficiency management is crucial, given the high amount of energy (electrical and thermal) required by the production cycle. This study presents the preliminary results of a research project aimed at defining the benefits of using combined heat and power (CHP) systems in the ceramic sector. Data collected from ten CHP installations allowed us to outline the average characteristics of prime movers, and to quantify the contribution of CHP thermal energy supporting the dryer process. The electric size of the installed CHP units resulted in being between 3.4 MW and 4.9 MW, with an average value of 4 MW. Data revealed that when the goal is to maximize the generation of electricity for self-consumption, internal combustion engines are the preferred choice due to higher conversion efficiency. In contrast, gas turbines allowed us to minimize the consumption of natural gas input to the spray dryer. Indeed, the fraction of the dryer thermal demand (between 600–950 kcal/kgH2O), covered by CHP discharged heat, is strictly dependent on the type of prime mover installed: lower values, in the range of 30–45%, are characteristic of combustion engines, whereas the use of gas turbines can contribute up to 77% of the process’s total consumption.

Flow investigation of cross-flow turbine using CFD method

Cross-flow turbine is one of prime mover type that is simple, capable to extract water power and easy to be manufactured. The runner is working at 2 stages. The need of high momentum has lead researchers to design water nozzle, blades, as well as the set-up between nozzle and runner. High momentum water nozzle and cross-flow runner has been designed individually with the same design criteria. Unfortunately, experimental testing may not gain specific flow pattern inside the nozzle and the runner. The purpose of this study is to investigate the flow pattern inside the nozzle, runner using CFD method, Ansys 2019 R3 academic version. The CFD simulation done 3-dimensionally with 5 nozzle inlet velocity variations: 2 m/s, 3 m/s, 4 m/s, 5 m/s and 6,487 m/s. The fluid is assumed to be 1 phase, using mesh with 17.750 nodes, inlet fluid pressure 1,05 Pa, and temperature 24,85°C. The results showed that the lowest velocity and pressure for variation 1 at 1st stage (v1) = 6,65 m/s and (p1) = -11931,5 Pa, and the highest velocity and pressure at 1st stage (v5) = 21,72 m/s and (p5) = -127521 Pa. At 2nd stage, variation 1 and 5 resulting velocity (v1) = 1,78 m/s and (p1) 593,264 Pa, (v5) = 5,83 m/s and (p5) = 6360,32 Pa respectively. The main different of the flow pattern between 5 inlet velocity variations is the final flow thickness inside the runner get thicker at higher velocity, which is assumed to gain more rotational velocity.

Effect of Prime Mover's Characteristics on the Survivability of a Synchronous Generator-Based Distributed Energy Resource During Transient Overload Conditions

Recently, prime-mover stalling phenomenon was observed in a synchronous generator-based distributed energy resource (DER) for large step load changes during experimental testing at the Consortium for Electric Reliability Technology Solutions Microgrid. It is found to highly impact the generator's survivability during transient overload conditions. The stalling occurs in synchronous generator-based DER because of a sustained imbalance between electrical load demand and mechanical power available from the prime mover, thus depleting the generator's stored kinetic energy. In particular, mechanical power capability of the prime mover and stored kinetic energy in the rotating mass are the causal factors. This article evaluates two different types of prime movers—reciprocating engine and combustion gas turbine—for the DER survivability. The characteristics of these two commonly used prime movers are investigated during transient overload conditions by simulation case studies using PSCAD/EMTDC software.

Selection of prime mover for combined cooling, heating, and power systems based on energy savings, life cycle analysis and environmental consideration

Selection of prime mover type was investigated for use in combined cooling, heat and power systems. Selection was determined from comparison of performance criteria for economic, energy and emissions savings. Simulations were run for three different types of prime movers in one climate zone and compared to a reference case with a typical separate heating and power system in the same climate zone. A hybrid load following method was implemented, with a suggested improvement. Performance parameters were compared and results indicated emissions and energy savings for all three prime movers. The prime mover types were reciprocating internal combustion engine (ICE), micro-turbine and phosphoric acid fuel cell. The climate zone was chosen to be a cold, humid climate represented by Chicago, IL. Economic savings were seen for both the ICE and micro-turbines. Emissions savings for carbon, nitrogen-oxides and methane, for all three types, were greater than 9%, 12%, and 13%, respectively. Primary energy consumption savings for all three were greater than 8%.

Design and optimization of a thermoacoustic heat engine using reinforcement learning

The thermoacoustic heat engine (TAHE) is a type of prime mover that converts thermal power to acoustic power. It is composed of two heat exchangers (the devices heat source and sink), some kind of porous medium where the conversion of power takes place and a tube that houses the acoustic wave produced. Its simple design and the fact that it is one of a few prime movers that do not require moving parts make such a device an attractive alternative for many practical applications. The acoustic power produced by the TAHE can be used to generate electricity, drive a heat pump or a refrigeration system. Although the geometry of the TAHE is simple, the behavior of the engine is complex with 30þ design parameters that affect the performance of the device; therefore, designing such a device remains a significant challenge. In this work, a radical design methodology using reinforcement learning (RL) is employed for the design and optimization of a TAHE for the first time. Reinforcement learning is a machine learning technique that allows optimization by specifying 'good' and 'bad' behavior using a simple reward scheme r. Although its framework is simple, it has proved to be a very powerful tool in solving a wide range of complex decision- making/optimization problems. The RL technique employed by the agent in this work is known as Q-learning. Preliminary results have shown the potential of the RL technique to solve this type of complex design problem, as the RL agent was able to figure out the correct configuration of components that would create positive acoustic power output. The learning agent was able to create a design that yielded an acoustic power output of 643.31 W with a thermal efficiency of 3.29%. It is eventually hoped that with increased understanding of the design problem, in terms of the RL framework, it will be possible to ultimately create an autonomous RL agent for the design and optimization of complex TAHEs with minimal predefined conditions/restrictions.

Comparison of different scenarios in optimal design of a CCHP plant

Optimal design of a combined cooling, heating and power (CCHP) generation system is presented in this paper. The goal of this study is to compare different outcomes which might be obtained during CCHP equipment selection due to following different scenarios: (1) when selecting the type of prime mover (PM, such as gas turbine or gas engine or diesel engine), what differences could be obtained when the selected nominal power of all PMs is similar (SNP) or they be selected non-similar (NSNP)? (2) What differences could be reached when selling electricity to the grid is feasible (SELL mode) or not (NO SELL mode)? (3) What differences are going to occur when PMs could run at variable partial load (VPL) during a year or constant partial load (CPL) during a year? Particle Swarm Optimization (PSO) method was applied to select the CCHP equipment by maximizing the relative annual benefit (RAB) as the objective function. Optimization results for our case study showed that NSNP-NO SELL-VPL scenario showed 15.41%, 10.80%, and 5.23% growth in optimum value of RAB in comparison with that for SNP-NO SELL-VPL scenario for gas engine, diesel engine and gas turbine, respectively. Furthermore, for our case study, NSNP-NO SELL-VPL scenario showed advantage over NSNP-NO SELL-CPL case, with 26.80%, 27.72%, and 13.60% higher RAB values when gas engine, diesel engine, and gas turbine were selected. Finally, differences were 12.37%, 23.76%, and 11.09% when SNP-NO SELL-VPL and SNP-NO SELL-CPL scenarios were compared.

4E analysis and multi-objective optimization of CCHP using MOPSOA

Thermal modeling and optimal design of combined cooling, heating, and power generation system are presented in this article. Selecting the type and number of prime movers, their nominal power and operational strategy, the heating capacity of backup boiler and storage tank, the cooling capacity of electrical and absorption chillers as well as electric cooling ratio (the ratio of electrical chiller capacity to the demand cooling capacity) were considered as nine design parameters. Three types of prime movers including gas turbine, diesel engine, and gas engine were studied in this article. Multi-objective particle swarm optimization algorithm was applied to obtain the maximum actual annual benefit and exergy efficiency simultaneously. Actual annual benefit included the energy, economy, and environmental parameters, therefore with adding exergy parameters, 4 E analysis of combined cooling, heating, and power system was performed. The combined cooling, heating, and power system could run in two operation modes, named economical and electricity tracking modes. In the former case, it was allowed to sell the excess electricity to the network and in the latter, it was not allowed to sell the excess electricity to the grid. It was observed that actual annual benefit for the gas engine was higher than two other cases in economical mode. In electricity tracking mode, the gas engine and gas turbine were more profitable. In addition, the trends of optimum values of design parameters versus actual annual benefit and exergy efficiency in economical mode were investigated and the results were presented. Finally, the results of applying the assumptions of constant and variable running load of prime movers during a year were compared.

Optimum Sizing of the Prime Mover in a Medium Scale Gas Turbine CHP System

Optimum selection of prime movers in combined heat and power (CHP) systems is of crucial importance due to the fact that inappropriate choices reduce the benefits of CHP systems considerably. In the selection procedure, the performance characteristics of prime movers as well as economic parameters should be taken into account. In this paper, a thermo-economic method for selecting the optimum nominal power and planning the operational strategy of gas turbine as the prime mover of a medium scale (500–5000 kW) CHP system is presented. Appropriate relations for estimating thermodynamic and economic parameters of the system in the context of net annual cost criterion are introduced. Three modes of operation have been considered, namely, two-way connection (TWC) mode, one-way connection (OWC) mode, and heat demand following (HDF) mode. In TWC mode, buying electricity from the grid and selling the excess electricity to the grid are allowed. OWC mode is a situation in which it is only possible to buy electricity from the grid. In HDF mode, buying electricity from the grid and selling electricity to the grid are allowed. HDF mode of operation is considered to have the minimum waste of energy due to the fact that prime movers work in a condition at which the excess produced heat is minimal. As a way of dealing with the environmental concerns, the impact of carbon tax has also been studied. The proposed method has been used for a case study. It was observed that the optimum nominal powers in TWC mode, OWC mode, and HDF mode are 3.5 MW, 3.4 MW, and 0.8 MW, respectively. Furthermore, in order to determine the sensitivity of results to parameters such as cost of electricity, cost of fuel, and carbon tax, a comprehensive sensitivity analysis was conducted. It is noted that the proposed method may be used for other types of prime movers (such as internal combustion engines) as well as various sizes of combined heat and power systems.

A new method of real-time physical simulation of prime movers used in energy conversion chains

This paper focuses on exploring a new method of real-time replication of the dynamic behaviour of prime movers that drive rotating generators involved in energy conversion chains. Their behaviour depends on the mover’s mechanical characteristics and dynamical properties, such as inertia or friction coefficient, which are seldom known precisely. Being also dependent on the variations of the primary energy resource, not always controllable in its natural environment, this behaviour must be simulated by using a smaller and cheaper mover, whose model is sufficiently known such that to render it fully controllable. This paper explores the possibility that the desired real-time replication be achieved by means of a new method of tracking the mover’s rotational speed. To this end, various controllers, both linear and nonlinear can be employed. The design steps are provided for a PI controller, as well as for two nonlinear controllers, while focusing on the practical aspects of controller implementation. Their performance results are assessed comparatively on an experimental rig for two types of prime movers: one whose mechanical torque-speed characteristic is linear and a cross-flow water turbine, having a nonlinear torque-speed characteristic.

Distributed Generation Interface to the CERTS Microgrid

This paper focuses on the energy storage system and the power electronic interface included in microsources of the CERTS microgrid. CERTS stands for the Consortium for Electric Reliability Technology Solutions. The consortium was formed in 1999 to research, develop, and disseminate new methods, tools, and technologies to protect and enhance the reliability of the U.S. electric power system and efficiency of competitive electricity markets. To provide the plug-and-play feature and the power quality requirements of the CERTS microgrid, all microsources regardless of their prime mover type must have a unified dynamic performance. This necessitates attaching an energy storage module to some or all of the microsources. The storage module is attached to the prime mover through a power electronic interface that couples the microsource to the microgrid. Details of the energy storage module, the power electronic interface and the corresponding controls are described. Performance of an example microsource, which includes a synchronous generator, a storage module and an electronic interface, is studied. Dynamic performance of the example microsource when operating in the CERTS microgrid is evaluated based on digital time-domain simulations in the EMTP-RV software environment. Effectiveness of the storage module, the electronic interface and the corresponding controls in enhancing the microsource performance is verified.

Helmholtz-like resonators for thermoacoustic prime movers

In a thermoacoustic prime mover, high acoustic output power can be achieved with a large-diameter stack and with a cavity with a large volume attached at the open end of the resonator containing the stack. The combination of resonator and cavity makes the device Helmholtz-like, with special characteristics of the resonant frequencies and quality factor, Q. Analysis of its acoustic behavior based on a model of a closed bottle presents features that are useful for the development of such prime movers for energy conversion from heat to sound. In particular, the arrangement produces in the cavity a high sound level, which is determined by the Q of the system. Comparison with a half-wave resonator type of prime mover, closed at both ends, shows the advantages of the Helmholtz-like device.

Selecting the prime movers and nominal powers in combined heat and power systems

Combined heat and power (CHP) systems have many economical and environmental benefits. Generally, selection of these systems is being performed using the time-dependent curves of the required electricity and heating load during a year. In the selection of a CHP system, the operation of this system at off-design point also should be studied. In this paper, a new and relatively quick method for selecting the number of each type of prime mover, and determining their nominal power and operational strategy considering specific electrical and heating loads is presented. Three types of prime movers which are studied in this paper are gas turbine, diesel engine, and gas engine. It was found that the ambient conditions, electricity and heating loads, fuel type, its heating value and price, and price of buying and selling electricity, affect the results considerably. The operational strategy was also studied in two economical and electricity tracking modes. In the former case it was allowed to sell the excess electricity to the network. In the latter, the engine had to operate to supply just the required electricity. The appropriate required boiler heat capacity was estimated in the two above mentioned cases.

A general technoeconomic and environmental procedure for assessment of small-scale cogeneration scheme installations: Application to a local industry operating in Thrace, Greece, using microturbines

Abstract The present paper describes a proposed general systematic procedure for small-scale combined heat and power (CHP) exploitation (where “small-scale CHP” refers to CHP installations with electric capacities up to 1 MW). The mentioned systematic procedure is implemented through a developed computer code and may be applied to any such small-scale project in order to assess its suitability based on technoeconomic and environmental considerations. A dynamic database based on small-scale CHP units (available in the world market) and their pertinent technical, economical and environmental features is created and, in conjunction with the developed program, is used for determination of a suitable CHP unit (or system) size and the selection of the associated proper prime mover type for any project of interest. Using well-known economic criteria, the economic analysis is performed, including the sensitivity analysis of the considered project based on the main key system parameters. In terms of the socioeconomic analysis, a carbon tax (CT) scenario is considered, and its effect on the economic behavior of the project is investigated. Last, with respect to environmental considerations, the program calculates, for any such project, the avoided main pollutants and the fuel savings when a CHP system is applied. As a case study, a small textile industry operating in the Eastern Macedonia-Thrace Region of Greece is considered, and its associated (electrical and thermal) data are used as input data to the proposed computer program. In this application, two microturbine units are selected and thoroughly evaluated, and the pertinent simulation results are presented and discussed accordingly.

Cogeneration Efficiencies and Economics

ABSTRACT The magnitude of cogeneration plant efficiency cannot, by itself, prove the plant's feasibility. The most reliable way to determine the feasibility of a cogeneration plant is to compare its performance versus a conventional scheme of generating electric power by a utility and obtaining thermal energy (steam, hot water) from a boiler. For such a purpose, and for comparison of different types of prime movers (steam turbines, gas turbines, combined cycles, and reciprocating engines), the most convenient way is to convert the electric power output into thermal units, and to base the comparison on HHV.

Information on micro-enterprises involved in cassava and palm oil processing in the Osun and Ondo states of Nigeria

Micro-enterprises involved in post harvest processing play a key role in the economies of less developed countries as a basic source of goods, income and employment especially for women. A study was undertaken to assess the capacity and technology needs of women agro-processors in Osun and Ondo states with a view to better understand their characteristics, problems and needs. This paper reports on some general information about agro-allied micro-enterprises that are useful to project planners and assisting agencies. The number of micro-enterprises established by individuals in the food processing sector has increased significantly over the last ten years. Group owned enterprises are usually government assisted and these groups need training in the art of business management. Infrastructural facilities at processing centres are inadequate. Inadequate supply of water affects the process and product hygiene and environmental cleanliness especially during the dry season and requires urgent intervention. Half walled structures are recommended for food micro-enterprises for effective ventilation. The sex of the machine operator is dependent on the type of prime mover. Petrol engines are operated by women and diesel engines by men. The study revealed a poor operational and maintenance practices of equipment by operators and this has reduced their functional life span to about five years. With proper training, the functional life of these equipment can be prolonged. Mode of transporting raw materials to the processing centres is grossly inadequate and limits the quantity of materials available for processing resulting in under utilisation of equipment capacity. Recommendations are made that can enhance the programme of donor/government agencies in achieving their objectives taking into consideration the information provided by the study.

Generator synchronizing industry survey results

This report presents the results of an extensive survey of electric utility practices for synchronizing a generator to the power system. The survey was constructed to collect data defining the present electric utility practice of synchronizing, the types of schemes used, why they were selected, and how they have performed. The survey also collected data detailing the number of machines equipped with a manual, semiautomatic, or automatic synchronizing scheme. This data is categorized by generator prime mover type and load classification.

INDUCTION GENERATORS-A PROSPECTIVE

Abstract The growing popularity of the induction machine operating as a generator for low cost electric power generation from renewable energy sources such as micro-hydro, wind etc., has attracted the attention of technologists all around the world. In this paper, the modes of operation of the induction generators, potential applications, types of prime movers and detailed schemes for electric power generation are described. The technology status on generating systems alongwith cost effectiveness involving induction generators are given to suit them for wide variety of situations. Generating schemes for constant speed and variable speed prime movers are discussed using squirrel cage and slip-ring induction machines with other controlling equipments. The suitable guidelines are also given for the design of electrical parts of generating system.