Static Coefficient Research Articles

MODEL EVAKUASI KERAMAIAN DALAM GEDUNG MEMILIKI BEBERAPA PINTU KELUAR DENGAN MEMPERHATIKAN KEPANIKAN INDIVIDU

The purpose of this study is to determine the effect of panic on evacuation time. Evacuation is the movement of individuals from a place in danger to a safer place. Evacuation is usually done when there is an emergency such as an earthquake, fire or attack, which will make the movement of individuals difficult. Individuals who are in an emergency will feel panic. The panic that occurs will cause individuals to lose their way to a safer place such as an exit. This research is a basic or theoretical research. The evacuation model uses cellular automata that simulates the behavior of individuals in cells for the evacuation process. This model considers the panic factor in the evacuation process which will affect the steps taken by individuals. Individual steps based on transition probabilities will obtain evacuation time. The parameters used are static coefficient, dynamic coefficient, and panic coefficient. Simulation using software by entering the grid size, obstacle position, exit position, individual position and parameters. Based on the simulation results, it is obtained that the increase in individual panic, the longer the evacuation time

EFFICIENCY OF POLYMER MATERIALS IN HIGHLY LOADED SYSTEMS IN THE AVIATION INDUSTRY

The static coefficient of friction was calculated on an inclined plane tribological stand. Different specimens and masses loading the system were used during the experiment. Surface-to-surface contact was tested in a pin-on-plate setup. The tested polymer pairs were POM on POM, PA6 on PA6 and PET on PET. The variables in the experiment were different pressures acting on the friction pair, and dry and lubricated friction was tested. Static coefficients of friction for each case was calculated and the surface quality of the pin and plate was measured by profilometer and optical microscope. The coefficient of static friction was higher for lubrication friction than the dry friction. It was also observed that the coefficient of friction decreases with increased load. POM – POM pair had the lowest coefficient of friction under dry conditions, while for lubricated friction, PA6 – PA6 had the most stable increase of friction coefficient.

Static friction measurement methodology for the assessment of performance of industrial valves at high temperatures: Case study for a nickel-based alloy coating

High static friction between functional surfaces poses a serious challenge for industrial valves, particularly for those used in the advanced ultra-supercritical power generation industry that requires raising the steam temperature to 760 °C. In this context, we established the static friction measurement methodology by evaluating the effects of temperature, loading time, and number of static cycles on the evolution of the static coefficient of friction up to 800 °C. This methodology was applied on a nickel-based solid lubricant coating that appears an attractive candidate to withstand very harsh environments. The tribological behavior is explained in terms of a competition of three mechanisms governing the static friction processes: micro-welding or sintering of asperities, creep of asperities, and formation of lubricious oxides.

Ontogenetic and static scaling of antler mass in White-tailed Deer (Odocoileus virginianus)

Abstract Antlers are a costly trait that require skeletal reserves to grow to a large size. Thus, insight into variation in antler size requires understanding the connection between antler and body size, which can be summarized through ontogenetic and static scaling relationships. Both types of scaling relationships are also needed to examine the influence of factors besides body mass on antler growth at different ages and whether the effects of these factors diminish with age. Dietary and maternal effects might decline with age as individuals attempt to mitigate size deficits. We examined the potential effects of diet and maternal attributes of dam (mother) age at birth and litter size on body–antler mass relationships throughout ontogeny and at discrete ages. Data on age, maternal characteristics, body mass, and antler mass were gathered from captive, pen-raised White-tailed Deer (n = 168) that consumed either a low-energy (1.77 kcal/g) or standard-energy diet (2.65 kcal/g) from the time they were weaned until they perished by 5.5 years of age. Both types of scaling relationships were estimated with linear mixed-effects models to account for repeated measurements of males, dams, and sires. Diet affected ontogenetic scaling relationships. Males eating the low-energy diet had faster antler growth when young and lighter in body mass than when they were older and heavier—whereas males fed the standard-energy diet had a similar rate of antler growth across the range of body masses. A Bayesian Information Criterion model selection analysis indicated that diet and litter size (singleton, multiple births), but not dam age at birth influenced static scaling relationships. Static scalar coefficients up to 3.5 years of age were positively allometric (>1.0), but isometric (1.0) in 4.5- and 5.5-year-old males. Furthermore, diet and litter size influenced both intercepts and slopes in only the youngest males (1.5 years) indicating that dietary and maternal effects can diminish with age. Body–antler mass relationships are complex. Young males that are small because of maternal effects, for example, might still be able to mitigate smaller body and antler sizes at older ages.

Determining the dynamic characteristics of a class B fire in the case of extinguishing by water spray

The object of this study is a class B fire, which is extinguished with sprayed water. The subject of the study is the characteristics of class B fires when they are extinguished with sprayed water. Diffusion burning of a flammable liquid is considered as such a fire, and its extinguishing is carried out by cooling the flame. Heat and oxygen balance equations are used to build a mathematical model describing the fire extinguishing process. The components of the heat balance equation are the power of heat during heat release due to the chemical reaction of liquid combustion and the power of heat dissipated to the environment. The second component takes into account heat removal due to radiation, convection, and evaporation. The component of removed heat due to evaporation takes into account the Sreznevsky constant. The mathematical model that describes the process of extinguishing a class B fire is built in the class of models belonging to differential equations with constant coefficients. Analytical expressions were obtained for these static and dynamic coefficients, which include thermophysical, kinematic, and geometric parameters of the flame and fire extinguishing agent. To determine these characteristics, the constructed mathematical fire model was transformed using the integral Laplace transform. The dynamic characteristics of the fire were obtained in the time domain – the transient function of the fire, and in the frequency domain – the amplitude-frequency and phase-frequency characteristics of the fire. It is shown that the parameters of these dynamic characteristics should be determined experimentally. Experimental methods for determining parameters of dynamic fire characteristics have been devised. The presence of dynamic characteristics of class B fire makes it possible to spread the proven methods of the theory of control systems to design effective fire extinguishing systems

Moisture dependent physical, mechanical, and aerodynamic properties of Simarouba glauca seed: A potential tree born oilseed

AbstractThe present study investigates the moisture dependence of the physical, mechanical and aerodynamic properties of Simarouba seeds within the moisture range of 9.24‐22.46% d.b. The length, width and thickness significantly increased from 19.43 to 22.71 mm, 11.52 to 13.88 mm and 9.79 to 11.34 mm respectively. Our findings showed significant effect of moisture content on the one thousand unit mass, bulk density, true density, and porosity which varied in the range of 1050.41g and 1204.7g, 638.88 to 503.88 kg∙m−3, 999.57 to 970.26 kg∙m−3 and 36.08% to 48.06%. Moisture content was found to have positive effect on the angle of repose terminal velocity and static coefficient of friction for all surfaces studied. A decreasing trend in rupture force and increasing trend in deformation with moisture content was also observed. The understanding of these properties as per the present study would be useful for designing post‐harvest processing equipment and storage of Simarouba seeds.Practical applicationsSimarouba glauca, D.C. is an evergreen potential tree born oilseed tree with high scope for biodiesel and edible oil production. The oilseed is presently underutilized due to lack of availability of suitable processing equipment. The findings of the study provide a comprehensive design database related to engineering properties of Simarouba seeds. The predictive models developed in this study can be used to assess the seed properties at any given moisture content range. The enrichment of database would serve as a guide for agricultural engineers, and food processors in the design and development of relevant post‐harvest handling, and processing equipment for Simarouba seeds. This may further lead to promotion of Simarouba processing as a promising enterprise in rural India.

Engineering properties and optimization of the dehulling process for hairless canary seed.

This work aimed to determine the engineering properties of hairless canary seeds (Phalaris canariensisL.) of the variety "CDC Maria" and the optimum combination of operating conditions of the dehulling process with a pilot-scale centrifugal dehuller. The engineering properties analyzed in this study were the principal dimensions, length (4.8mm), width (1.95mm) and thickness (1.41mm); geometric mean diameter (2.36mm); the sphericity (49.2%); apparent and true densities (752 and 1191.47kg/m3, respectively); the porosity (0.37); 1000 grains weight (7.28g); angle of repose (15.89°) and the static coefficient of friction (galvanized steel, 0.325; plywood, 0.372; aluminium, 0.316). For the process optimization, a two-variable Doehlert design was used, analyzing the effect of impact dehuller rotor speed (peripheral speed 30.4 to 47.1m/s) and seed moisture content (10 to 14% d.b.) by maximizing the dehulling ability (DA) and maintaining the production of fines by 3%. Under the experimental conditions of 36.7m/s (peripheral speed) and 10% d.b. (seed moisture), with a double pass through the dehuller, the optimum value of DA (94%) was obtained, with a fine production of 3%. The optimized dehulling process allows removing a large percentage (98%) of the canary seed hull.

Prototype Test of Resilient Friction Materials for Seismic Dampers

In recent decades, low-yielding seismic devices based on the use of friction dampers have emerged as an excellent solution for the development of building structures with improved reparability and resilience. Achieving an optimal design for such low-yielding seismic devices requires precise control of bolt preloading levels and predictability of the friction coefficient (CoF) between the damper interfaces. While various types of friction devices exist that are capable of providing significant energy dissipation, ongoing research is focused on the development of novel friction materials that exhibit a stable hysteretic response, high CoF values, minimal differences between static and dynamic CoF, and predictable slip resistance. In this context, an experimental campaign was conducted at the STRENGTH Laboratory of the University of Salerno to evaluate the behaviour of new friction shims employing specially developed metal alloys. Specifically, the influence of the characteristics of the contact surfaces in the sliding area on the behaviour and performance of the friction device was analysed. The tests followed the loading protocol recommended by EN12159 for seismic device qualification. Monitored parameters included preloading force values and the evolution of slip resistance. The friction value was determined, along with its degradation over time. Finally, the material’s performance in terms of hysteretic behaviour was assessed, providing a comparison of the tested specimens in terms of slip force degradation and energy dissipation capacity.

One-way fluid structure interaction analysis of a static savonius hydrokinetic turbine under different velocity and surface roughness with different blade materials

Hydrokinetic turbines are prone to a harsh hydrodynamic environment with intricate vortical flows that elevate the probability of failure. The degradation of the blade surface caused by corrosion can impact the blade's hydrodynamic and the structural performance. This paper reports a one-way three-dimensional fluid-structure interaction simulation to analyse the performance of a static Savonius hydrokinetic turbine at varying rotor positions, with different surface roughness and water velocities, in terms of coefficients of static torque, static torque, stresses, and blade deformation. The simulations revealed that the optimum position for the highest coefficient of static torque was at 15° (Cst = 0.30) in reference to the water flow. Increasing the water velocity from 0.4 ms−1 to 0.84 ms−1 improved the turbine static torque due to an increase in the kinetic energy. However, the presence of surface roughness has deterioration effects on the static torque coefficient due to a delayed separation which causes a drag reduction. The simulation predicted no structural failure at 0.4 ms−1 and 0.84 ms−1, but varying materials exhibited varying maximum principal stress and deformation, highlighting the significance of the early development of materials selection process. The maximum von Mises stress and deformation was obtained when the turbine is resting at 45° for aluminium blade (σ = 1.05 MPa, ε = 5.6e−4 mm). The results of this study indicate suitable materials from a hydrodynamic and material perspectives for the construction of the Savonius hydrokinetic turbine, which can be implemented in the design process to potentially save cost and minimize turbine downtime.

Large-Eddy Simulation of Flow Separation Control in Low-Speed Diffuser Cascade with Splitter Blades

The passive flow control technology of using splitter blades in low-speed diffuser cascade was investigated in this study. Based on the Reynolds average Navier-Stokes calculations, the arrangement parameters of the splitter blades were studied in detail to determine the optimal parameters. The large-eddy simulation was performed on the base case and the optimized splitter blade case to obtain the transient vortex structures and unsteady flow characteristics of the cascade. The results show that the aerodynamic performance of the cascade was susceptible to the position of the splitter blades. The optimal position of the splitter blades was located in the middle of the main blades near the leading edge. When the cascade was arranged with optimized splitter blades, the static pressure coefficient was improved and the stall occurrence was delayed. The scale and intensity of the separation vortices generated on the suction surface of the main blade decreased. In addition, the separation vortices of the main blade and the splitter blade interacted and rapidly decomposed into small-scale vortices downstream of the cascade, reducing the flow loss. The stability of the cascade was enhanced.

Parametric optimization applied to design a high-performance vaneless-diffuser for CO2 centrifugal compressor

ABSTRACT Carbon-dioxide (CO2) centrifugal compressors are machines with high potential of usage in power generation plants and oil industry as it achieves high thermal efficiency in the Brayton cycles and contributes to oil production through the capture and storage of CO2 (CCS) in EOR (Enhanced Oil Recovery) systems. High levels of static pressure at the outlet are desired for EOR applications, which are usually obtained through the insertion of vanes in the diffuser. This work intends to increase vaneless-diffuser static pressure recovery by modifying only its meridional profile, ensuring a broader range of off-design operation when compared to vaned diffusers and attending to the fluctuations of mass flow and rotation expected in EOR practical applications. Therefore, a parametric optimization through surrogate model coupled to CFD was performed with three different objective functions that were submitted to single-optimization through the NSGA-II method: Maximize total-to-total polytropic efficiency, minimize total pressure loss coefficient or maximize static pressure recovery coefficient. Additionally, a sensitivity analysis was conducted using Morris Elementary Effects and SS-ANOVA. The results indicated that the optimized geometries increased the total-to-total polytropic efficiency by 2.9%, reduced the total pressure loss coefficient by 24.0% and increased the static pressure recovery coefficient at the design point by 11.4%, which is discussed in detail after a careful phenomenology assessment. The strategy adopted in the present work through a combination of Sensitivity Analysis, surrogate models and CFD increased the vaneless-diffuser static pressure recovery without the need of inserting vanes in the diffuser, which avoid instabilities in the equipment and would restrict its range of off-design operation.

Features of design calculation of compressor spool flow path of a twin-shaft gas turbine engine core on the basis of 1D and 2D models of their working process

The features of the stages of parameter design calculation for the formation of the initial design of the flow path of the compressor spool of a twin-shaft engine core of a gas turbine engine are presented and substantiated. The article contains recommendations for choosing values of the pump head coefficient, efficiency and other important parameters for the stages of medium-pressure and high-pressure spools at the stage of thermodynamic calculation. At the stage of design gas-dynamic calculation of the compressor at the middle diameter, typical distributions of axial velocity component and degree of reaction along the flow path of compressor spools should be taken into consideration. At the same time, it is necessary to provide requirements for reducing the flow velocity and static pressure coefficients in the rotor wheels and stator blades, head coefficients and Stepanov coefficients. The design gas-dynamic calculation of the compressor along the radius of the flow path is characterized by a variety of flow swirl laws at the inlet to the rotor wheels, distributions of the pressure increase and efficiency over the height of the blades. In conclusion, an example of a three-dimensional model of a compressor flow path taking into consideration the features of design calculation of the parameters of compressor spools of a twin-shaft engine core of a gas turbine engine on the basis of the appropriate flow path diagram in the meridional plane is presented.

Wind tunnel experimental study on static aerodynamic performance of SB-VAWT without intermediate support axes

Wind power generation is considered an effective way for ships to harness wind energy, and the aerodynamic characteristics of wind turbines determine wind energy utilization and efficiency. However, traditional vertical axis wind turbines have intermediate shafts and support rods, which result in large negative effects in the research of the wind turbine aerodynamic characteristics. To address this issue, a Straight-Bladed Vertical Axis Wind Turbine (SB-VAWT) without intermediate support axes is proposed. The turbine can flexibly change the number of blades, rotor diameter, and installation position of blades. The static aerodynamic performance of the wind turbine with different combinations was tested in a wind tunnel laboratory at 10 m/s. The results show that the radius of the wind turbine has a greater effect on the drag coefficient for the same number of blades, with an inverse relationship between the drag coefficient and radius, and a positive association between lift coefficient, static torque coefficient, and radius. The drag coefficient is proportional to the number of blades at the same radius, while the static torque coefficient is inversely proportional to the number of blades. According to the results, placing the initial location in the azimuth range between 30° and 50° can obtain the maximum initial starting torque. Moreover, a wind turbine with a radius of 16 cm can achieve a higher average torque. Changes in the number of blades can significantly impact turbine properties, resulting in wind turbines with distinct features.

Enhancing vertical axis wind turbine efficiency through leading edge tubercles: A multifaceted analysis

This research paper aims to investigate the impact of leading edge tubercles (LET) on the performance of hybrid vertical axis wind turbine (VAWT). The study involves both experimental and computational analysis of a novel hybrid VAWT configuration. The proposed VAWT design is characterized by a high power coefficient and self-starting capability. To provide a basis for comparison, an existing hybrid VAWT without tubercles and a conventional H-Rotor Darrieus design were also examined. The findings indicate that the proposed hybrid VAWT achieved the highest power coefficient (Cp) of 0.475 at a tip speed ratio (TSR) of 3. Furthermore, the proposed wind turbine demonstrated superior Cp values at both low TSRs (1 to 2.1) and high TSRs (4.1 to 5) compared to the existing hybrid VAWT and the H-Rotor Darrieus turbine. The positive static torque coefficient (Cts) values observed at all azimuths, with a maximum value of 0.319, highlight the self-starting capability of the proposed hybrid wind turbine. The enhanced power coefficient and the ability to harness wind energy even at low wind speeds make the proposed hybrid wind turbine suitable for a wide range of power projects, from small to large-scale. This approach offers a means to determine the optimal design configuration for a hybrid VAWT and facilitates a detailed analysis during the early design stages, along with its high-fidelity characteristics.

A research for the effectiveness of stitch type and stitch direction on dynamic drape behaviors

PurposeThe purpose of this study is to explore the effect of stitch type and stitch direction on the dynamic drape behavior of the woven fabric.Design/methodology/approachIn this paper, the effectiveness of stitch type and stitch directions on dynamic drape behaviors were investigated. Fabric parts were sewn together with two types of the stitch (lockstitch and overlock stitch) on three different stitch directions (warp, weft and bias (45°)). The static drape coefficients (SDC) of unsewn and sewn fabrics were measured according to the image process method. Dynamic drape coefficients (DDC) of fabrics were also measured using the same method at six different (25, 50, 75, 100, 125, 150 rpms) rotation speeds. Additionally, bending length and bending rigidity were measured using the Cantilever test method.FindingsExperimental results showed that stitch type and stitch directions are effective on the dynamic drape behaviors of the fabric. Overlock stitch resulted in greater DDC than the lock stitch. For both of the stitch type, DDC for the stitch on the warp direction are greater than the stitch on the weft and bias direction for all speeds. In addition, bending length, hence the bending rigidity, are greater for overlock stitch type and always weft direction resulted in greater than the warp and bias direction.Originality/valueFabric drape is vital for garment appearance and is gaining popularity with the advancement of virtual technology, enabling virtual visualization of garments. While previous studies have predominantly examined either the static or dynamic drape behavior of individual fabric panels, or solely focused on the static drape behavior of sewn fabrics, this study acknowledges the significance of incorporating the influence of stitch type and direction on dynamic drape behaviors. Considering that fabrics are sewn together to create garments and that DDC provides a more accurate representation of real-time fabric behavior compared to SDC, this research makes a valuable contribution to the existing literature by investigating the impact of stitch type and direction specifically on DDC.

Damage-coupled unified constitutive modeling of 316LN stainless steel including dynamic strain aging under various tension dwell time: A macroscopic phenomenological study

A damage-coupled unified constitutive model is developed for 316LN stainless steel based on the framework of the Abdel-Karim and Ohno model. In the modified model, a kinematic hardening coefficient related to accumulated plastic strain is introduced in the linear hardening term, and a damage coefficient is incorporated in the static recovery term. Meanwhile, the parameters of isotropic hardening and kinematic hardening are associated with the maximum plastic strain rate and plastic strain memory to describe the effects of dynamic strain aging and plastic strain memory. Additionally, the kinematic hardening coefficients and static recovery coefficients correlate with dwell time to simulate stress relaxation throughout the whole-life time. The comparison between the simulation and experimental results indicates the validity of the modified model under the conditions of low-cycle fatigue and creep-fatigue interaction. After identifying the material parameters using a combination of classic parameter determination methods and optimization algorithms, the cyclic stress response and hysteresis loops can be accurately simulated throughout the whole-life time.

Measurement of Effective Hydrogen-Methane Gas Diffusion Coefficients in Reservoir Rocks

Summary If hydrogen is stored in depleted gas fields, the remaining hydrocarbon gas can be used as cushion gas. The composition of the backproduced gas depends on the magnitude of mixing between the hydrocarbon gas and the hydrogen injected. One important parameter that contributes to this process of mixing is molecular diffusion. Although diffusion models are incorporated in the latest commercial reservoir simulators, effective diffusion coefficients for specific rock types, pressures, temperatures, and gas compositions are not available in the literature. Thus, laboratory measurements were performed to improve storage performance predictions for an underground hydrogen storage (UHS) project in Austria. An experimental setup was developed that enables measurements of effective multicomponent gas diffusion coefficients. Gas concentrations are detected using infrared light spectroscopy, which eliminates the necessity of gas sampling. To test the accuracy of the apparatus, binary diffusion coefficients were determined using different gases and at multiple pressures and temperatures. Effective diffusion coefficients were then determined for different rock types. Experiments were performed multiple times for quality control and to test reproducibility. The measured binary diffusion coefficients without porous media show a very good agreement with the published literature data and available correlations based on the kinetic gas theory (Chapman-Enskog, Fuller-Schettler-Giddings). Measurements of effective diffusion coefficients were performed for three different rock types that represent various facies in a UHS project in Austria. A correlation between static rock properties and effective diffusion coefficients was established and used as input to improve the numerical model of the UHS. This input is crucial for the simulation of backproduced gas composition and properties which are essential parameters for storage economics. In addition, the results show the impact of pressure on effective diffusion coefficients, which impacts UHS performance.

Effects of Synthetic Jets on Swirl Inflow in a Variable-Geometry Twin Air-Intake

Air intakes are an integral part of contemporary passenger and military aircraft engines. Their impact on aerodynamic performance across the entire flight envelope is critical to aircraft flight safety, efficiency, and manoeuvrability, especially at high Mach numbers due to shock waves. The high demand for reductions in aircraft weight and size and enhancements in durability, comfort, and thermal and radar signatures compel researchers and engineers to explore new designs and develop efficient air intakes for high-performance aircraft engines. Although a number of studies on air intake have been conducted and reported in the open literature, there is little information available in the public domain on bifurcated twin air intakes using synthetic jet. As a result, the primary goal of this research is to use computational fluid dynamics modelling to investigate the effects of synthetic jets on swirl inflow variable geometry twin air intake aerodynamic performance over a range of Reynolds numbers. Some important parameters (distortion coefficient, non-uniformity index, swirl coefficient, and static and total pressure coefficients) were investigated. Both static and total pressure recovery have been increased at all swirl numbers. A significant decrease in distortion coefficient and swirl coefficient has also been achieved, reaching a 53% reduction in the distortion coefficient and a 62% reduction in the swirl coefficient. The reduction in the non-uniformity index is achieved by 62% for the controlled flow case. The findings show that synthetic jets are effective in controlling the flow separation in the twin air intakes and enhancing aerodynamic performance.

Moisture dependent postharvest physical and textural characteristics of brown sesame seed (var. TMV-4)

Physical and textural characteristics are important in design and manufacturing of harvest and post harvest machines. Some postharvest physical and textural characteristics of brown sesame seed (var. TMV-4) were determined as a function of moisture content in the range of 4.3 per cent to 20 per cent (d.b). The axial dimensions, geometric mean diameter, surface area, volume, sphericity and aspect ratio were found to be increasing linearly for all studied moisture levels. Furthermore, the thousand seed mass, true density, porosity and the angle of repose also increased linearly whereas, bulk density decreased linearly with the increase of moisture content under study. The results showed that the static coefficient of friction on four different surfaces of plywood, mild steel, galvanized iron and glass also increased linearly for all level of moisture. The initial cracking force, average rupture force and average rupture energy decreased linearly with increased moisture content of 4.3 to 20 per cent (d.b.).

Effect of Sharing Schemes on the Collective Energy Self-Consumption Feasibility

Collective self-consumption is called to be a crucial part of the current energy transition. In addition to the advantages of individual self-consumption, the possibility of improving economic feasibility exists. This paper shows how matching production and consumption loads increase the rate of self-consumption. Still, how the electricity is distributed among a renewable energy community’s prosumers would reduce the total costs of self-consumed energy. Possible criteria for the allocation of the generated electricity among shareholders are analysed. The study also evaluates the use of static and dynamic distribution coefficients, observing their results and applicability and sorting them to maximise self-consumption participants’ savings. The results are questioned against them and a reference scenario without shared self-consumption installation. As the exploitation of renewable energy for self-consumption is closely linked to the energy market and regulations, the analysis is based on a territorial case study. It is shown that the highest savings occur when electricity is allocated following distribution coefficients that consider the customer’s energy consumption better than investment participation or contracted power, even when the compensation of surpluses is added. These criteria can accomplish technical and economic objectives and are introduced in regulations that foster the requested changes in consumers’ behaviour and prosumers for sustainability.