Average Daily Load Research Articles

Occurrence, consumption level, fate and ecotoxicology risk of beta-agonist pharmaceuticals in a wastewater treatment plant in Eastern China

Beta-agonist pharmaceuticals are widely used in humans and livestock for disease treatment, legal or illegal growth promotion in food animals, bodybuilding, weight loss, and sports doping. The occurrence of beta-agonists in wastewater treatment plants and their subsequent environmental impacts require greater attention. This study determined the levels of 12 beta-agonists in a wastewater treatment plant and evaluated their ecotoxicological risks as well as consumption levels and risks to human health. Among the 12 selected beta-agonists, all were detected in wastewater and 11 in sludge. In most cases, the concentrations of beta-agonists were higher in spring than in summer. Their total average daily mass loads per capita in the influent and effluent were 1.35μg/d/p and 2.11μg/d/p, respectively. The overall removal efficiencies of individual beta-agonists ranged from -295.3 to 71.2%. Ecotoxicological risk assessment revealed a low risk to daphnid and green algae from the levels of fenoterol and the mixture of 12 selected beta-agonists in the effluent. The daily consumption levels of individual beta-agonists per capita were 0.028-1.200μg/d/p. Regular monitoring of beta-agonists in municipal sewage systems and their risk assessment based on toxicological data are urgently required in the future.

Electric Vehicle Charging/Discharging Models for Estimation of Load Profile in Grid Environments

The increasing electric vehicles (EVs) and their integration with the electrical networks to achieve the charging demands has highly affected the operation of the power system. These effects are due to the increased and variable amount of electricity consumption caused by the irregular charging patterns of EVs. As the EV penetration level increases with such irregular charging patterns, the overall load profile in a network will increase resulting in load peaks. To overcome this, a well-planned charging-discharging algorithm is needed for the EV users and the power suppliers. In light of the above issues and requirements, this paper proposes a Markov Chain Monte Carlo (MCMC) simulation-based EV charging (EVC) behavior models and charging-discharging power prediction models. The proposed methods analyze the traveling behavior of EVs, and their charging patterns to make EV a flexible load. This helps in understanding the variable electricity consumption and mitigating the peak loads and load variations. Further, to assess the operation of the proposed methods, the charging-discharging power prediction is carried out for a large EV fleet based on the historical data. The power predictions are carried out for 100 days and the convergence of the proposed algorithm is targeted to be kept below 0.5% to achieve optimal power prediction. The results showed the credibility of the proposed approach in identifying the daily average charging-discharging load curves.

An economic and technological analysis of hybrid photovoltaic/wind turbine/battery renewable energy system with the highest self-sustainability

Abstract This research established the technoeconomic feasibility of an on-grid hybrid renewable energy system for delivering electricity to the deanery building of the Engineering College at the University of Diyala, Iraq. The most cost-effective system design was discovered by modeling and optimization, with an average daily load of 25.0 kWh and total cost and energy cost of $5142 and $0.05/kWh, respectively. In relation to the energy generated by conventional resources, the designed system is more cost-effective and has a lower carbon footprint of about 13,052 kg/year of CO2 emissions avoided. According to the research, using a hybrid power system to electrify and decarbonize the electrical energy supply could be a reliable and economical way to do both at the same time. Innovation is in integrating the suggested hybrid system so that the use of electricity can effectively be decreased to meet the load. As a result, the system components are not oversized, which reduces system costs and reduces emissions.

Differentially Private K-Means Clustering Applied to Meter Data Analysis and Synthesis

The proliferation of smart meters has resulted in a large amount of data being generated. It is increasingly apparent that methods are required for allowing a variety of stakeholders to leverage the data in a manner that preserves the privacy of the consumers. The sector is scrambling to define policies, such as the so called ‘15/15 rule’, to respond to the need. However, the current policies fail to adequately guarantee privacy. In this paper, we address the problem of allowing third parties to apply <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> -means clustering, obtaining customer labels and centroids for a set of load time series by applying the framework of differential privacy. We leverage the method to design an algorithm that generates differentially private synthetic load data consistent with the labeled data. We test our algorithm’s utility by answering summary statistics such as average daily load profiles for a 2-dimensional synthetic dataset and a real-world power load dataset.

Antibiotics in wastewater of Guangdong, China: distribution patterns, and their environmental risk due to incomplete removal

In this study, the occurrence, removal, spatial distribution and environmental risks of ten antibiotics in 38 wastewater treatment plants (WWTPs) which located in 15 communities (in 12 cities) of the Guangdong province, China. The results indicated that amoxicillin (AMO, 381.00–5230.00 ng·L−1) and ofloxacin (OFX, 7.01–836.00 ng·L−1) were predominant in the province with high detection rates (100 %) and high concentrations. The concentration of norfloxacin (NFX) was high in some influents (2070.00 ng·L−1), but its detection rate was only 47.4 %. In addition, the average daily mass load per 103 capita (ADMLpc) of AMO (383.34 mg·(103 capita)−1·d−1) was significantly higher than the other antibiotics. The comparison between the ADMLpc and social-economic factors indicated that adult (age between 18 and 60) was the age group mainly consume antibiotics in the province. Furthermore, the ADMLpc of human antibiotics (e.g., AMO and OFX) were positively affected by the economic development of the region. Comparatively, the ADMLpc veterinary antibiotic (e.g., SMM) was positively related to the livestock related factors. In general, no significant difference (p > 0.05) in antibiotic removal efficiencies among four treatment processes applied in all WWTPs. Nevertheless, the low removal rates of sulfamethazine (SMZ, 44.6 %) and OFX (26.3 %) indicated that they were more difficult to be removed than other antibiotics. Furthermore, high ADMLpc of antibiotics in the influent would cause high ADMLpc in effluents. Therefore, heavy consumption of antibiotics could pose high risk to the ecosystem, especially when multiple antibiotics appeared in the effluent of the WWTPs.

Desain PLTS On-Grid 7 kW Di Gedung Kantor Polisi Pamong Praja Kabupaten Ende

PLTS converts electromagnetic energy from sunlight into electrical energy. On-Grid PLTS Design at the Civil Service Police Office of Ende Regency generates 7 kWp of power, with 35 panels used, each with a capacity of 200 Wp. The triangular roof area is 44m2. The inverter used is 1 unit with a capacity of 4 kW. The purpose of this study is to reduce the use of conventional PLN energy to meet energy needs at the Civil Service Police Station, Ende Regency. This plan requires a cost of Rp. 130.935.000. From the average daily load requirement of 35302 W/h, this plan produces 34450 W/h to meet 97% of the needs of the Ende District Civil Service Police Station.

Performance investigation of a grid-connected system integrated photovoltaic, battery storage and electric vehicles: A case study for gymnasium building

It has been a pressing challenge for human beings to reduce the energy consumption of buildings and decrease carbon emission. The application of photovoltaic (PV) system in buildings is identified as a renewable energy and carbon reduction approach. As a kind of typical building, the gymnasium usually has a large non-occupation roof area, which shows great application potential to cover the building demand by available photovoltaic source. This paper presents the performance of a grid-connected system integrated photovoltaic, battery storage, and electric vehicles (EV) applied in gymnasium buildings. The main building demand of gymnasium buildings can be easily covered by adopting an appropriate size of PV installation and battery capacity. The load cover ratio can achieve 0.95 when PV generation equals the energy consumption of the building and the battery with 2.7 times capacity of average daily building load is equipped. The proposed charging strategy for EVs can significantly decrease the peak power of the system compared with the constant power charging method. The peak grid power of the system adopted with the proposed charging strategy can be decreased by 51.7% of the rated load power on a typical day when PV generation is 1.4 times the energy consumption of the building and the battery capacity is 66% of the average daily building load. The results of this study show a reference for the configuration and operation scheme of PV system and electric vehicles in gymnasium buildings for renewable energy development and zero-carbon activity.

Consideration of some optimization techniques to design a hybrid energy system for a building in Cameroon

To solve the problem energy deficit encountered in developing countries, Hybrid Renewable Energy System (HRES) appears to be a very good solution. The paper presents the optimal design of a hybrid renewable energy system considering the technical i.e Loss of Power Supply Probability (LPSP), economic i.e Cost of Electricity (COE) and Net Present Cost (NPC) and environmental i.e Total Greenhouse gases emission (TGE) aspects using Particle Swarm Optimization (PSO), hybrid Particle Swarm Optimization-Grey Wolf Optimization (PSOGWO), hybrid Grey-Wolf Optimization-Cuckoo Search (GWOCS) and Sine-Cosine Algorithm (SCA) for a Community multimedia center in MAKENENE, Cameroon; where inhabitants have to spend at times 3 to 4 days of blackout. Seven configurations (Scenarios) of hybrid energy systems including PV, WT, Battery and Diesel generator are analyzed considering an average daily energy load of 50.22 kWh with a peak load of 5.6 kW. Four values of the derating factor i.e 0.6, 0.7, 0.8 and 0.9 are used in this analysis and the best value is 0.9. Scenario 3 with LPSP, COE, NPC, TGE and RF of 0.003%, 0.15913 $/kWh, 46953.0485 $, 2.3406 kg/year and 99.8 % respectively when using GWOCS is found to be the most appropriate for the Community multimedia center. The optimal Scenario is obtained for a system comprising of 18 kW of Ppv−rated corresponding to 69 solar panels, 3 days of AD corresponding to a total battery capacity of 241 kWh and 1 of Ndg.

Optimal planning of solar PV and battery storage with energy management systems for Time‐of‐Use and flat electricity tariffs

This paper determines the optimal capacity of solar photovoltaic (PV) and battery energy storage (BES) with novel rule-based energy management systems (EMSs) under flat and time-of-use (ToU) tariffs. Four schemes are investigated based on the combinations of flat and ToU tariffs for buying and selling the electricity: (1) Flat-Flat, (2) ToU-Flat, (3) Flat-ToU, and (4) ToU-ToU. For each scheme, two configurations are evaluated: (i) PV only, and (ii) PV-BES. The optimization of the grid-connected household is evaluated based on one-year realistic data. An uncertainty analysis is presented based on the variations of insolation, temperature, and load. Sensitivity analyses are implemented based on the average daily load, the grid constraint, and the costs of PV and BES. The operational analyses for 48 h in summer and winter are carried out to evaluate the dynamic performance of the systems for high and low solar insolation. The effectiveness of the proposed model is verified by comparing the results with that of common EMS based on the net metering scheme. It is found that the COE of the proposed EMS for a PV-BES house with ToU-Flat scheme (as the best option) is 2 ¢/kWh lower than that of the net metering scheme.

Optimal Dispatchable DG Location and Sizing with an Analytical Method, based on a New Voltage Stability Index

With the high penetration of DGS in the distribution network and its impact on the power loss and voltage profile of the network, the choice of location and the optimal size of the DG has become a challenge for utility companies. In this paper, a method for determining the optimal location and size of dispatchable DG at different load levels for optimal utilization of the distribution network is presented. The goal is to reduce active power losses and improve voltage profiles for stable system performance. The average daily load demand is considered as the load demand profile. The optimal location of DG is determined by sensitivity analysis based on a new voltage stability index. The voltage stability index is based on the voltage breakdown feature and provides an overview of the network voltage stability so that it can show the effect of DG installation location on network voltage stability. DG provides loads at different levels, then by selecting the appropriate bus from the most important buses in terms of index, the optimal size of DG is determined using a search algorithm and based on the lowest active power losses for different load levels. The proposed method on IEEE 33 bus network has been tested using MATLAB software, and its results have been compared with other available methods. The results show the effectiveness of the proposed method in reducing active power losses and improving the voltage profile compared to other available methods.

Contribution of rain events to surface water loading in 3 watersheds in Canada’s Alberta Oil Sands region

Study regionIn the oil sands region of Canada, hydrology of rivers is strongly influenced by snowmelt and a shifting climate resulting in shortening of snow cover duration and increases in the frequency of rain events. Study focusTo evaluate the importance of rain events to these rivers, discharge and water quality sampling was conducted at river sites in this region. Two approaches were used to collect water quality samples: (1) event-based automated samplers that triggered repeated sampling in response to 10% increases in surface flow, and (2) an intensive program of routine sampling at daily, weekly or biweekly intervals from April 2013 to January 2014. New hydrological insights for the regionThe importance of rain events as contributors to loading of nutrients and priority pollutants differed temporally. During fall, when baseflow conditions prevailed, average daily loads differed when calculated using routine only versus routine + rain-event data. However, on an annual basis, the inclusion of rain-event sampling did not change pollutant loads. Thus, when assessing loads on an annual basis, rain event sampling may not provide enough benefit to warrant the additional logistical considerations for this remote region. However, when monitoring focuses on capturing fall conditions, efforts should be expanded to include rain event sampling in order to capture spikes in chemical concentration during this ecologically important time period. Predictions of a shorter snow season with more precipitation falling as rain rather than snow reinforce the need to adapt monitoring schemes to ensure that the timing and frequency of water chemistry sampling reflects changing climate and hydrological patterns.

A Preliminary Assessment of Load Consumption and Solar Power Potential at Kota Belud, Sabah

This paper presents a detailed preliminary assessment of load consumption and solar power potential at the Eco-Tourism Centre of Liogu Ku Silou-Silou (EPLISSI), Kota Belud, Sabah. This initial investigation assessed the feasibility of an off-grid solar PV system at EPLISSI with a suitable solar panel system for project installation and commissioning purposes. Due to the absence of an electrical grid and power supply, no pre-existing electrical appliances could be found in EPLISSI. Hence, an excel-based software, the ESCoBox, was used to produce the load profiles. The input data for this software came from a list of required electrical appliances (LED lights, fans, and phone chargers) and the historical frequency of visitors to EPLISSI. Meanwhile, to assess the solar power potential at EPLISSI, an online simulator known as Global Solar Atlas version 2.3 or GSA 2.3 was used. As an input for the GSA 2.3, the initial solar panel system capacity was set for 0.5 kWp, and then an increment of 0.1 kWp was entered until specific criteria were met. The selection of the suitable size is made when the system can satisfy the daily total average load demand and a specific load fulfillment demand. As a result, it was found that the site requires a total average demand and a total peak demand of 4.60 and 11.87 kWh/day, respectively. From the GSA 2.3 generated report, an off-grid solar PV system with the capacity of 2.50 kWp solar PV can satisfy the daily total average load demand of this area, where the average PV energy output is within the range of between 7.74–9.80 kWh/day or an average of 8.72 kWh/day. In conclusion, this preliminary assessment indicates that installing an off-grid solar PV system in this area is possible.

Load Profile Validation for Design of Sustainable Optimal Hybrid Renewable Energy Systems

This study focuses on the validation of load profile and energy usage of Itie-Ikpe, a rural community located in the southern part of Nigeria, for the purpose of designing sustainable optimal hybrid renewable energy systems. A two-year monthly estimated load profile data was obtained from an energy distribution company, monthly averages and overall annual daily load demand of 557.59 kWh/d were determined using mathematical method while a field survey was conducted to obtain the actual load demand figure 562.25 kWh/d for the study community with a difference of 4.66 kWh/d. The two independent results were comparatively analyzed with the field survey result higher than the estimated value obtained from the energy distribution company by 0.84%. Findings also showed that the error margin or difference was relatively negligible with little or no significant effect on the design of the optimal hybrid renewable energy system. Therefore, the daily load demand figure from the field survey result validated the average daily load demand value determined from the obtained estimates. This validation is a crucial step in designing an optimal hybrid renewable energy system for energy sustainability of the study community, as the modeling and selection of systems components of the hybrid renewable energy system depends on the knowledge of accurate average daily load demand in order to avoid design of ineffective energy systems whose performances might not be optimal.

Web-based software application design for solar PV system sizing

The solar photovoltaic (PV) energy source systems generally rely on the availability of sunlight, its duration, and the capacity of storage devices if it is not a grid-tie system. The components of the PV sources come in different sizes and capacities, depending on the various applications and available products in the market. Therefore, sizing of PV components becomes important to the functionality and reliability of solar PV sources. This work is aimed at the development of a web-based software application designed for sizing the capacity of solar PV source components that meet required energy demand. A description of photovoltaic system components, available types, and sizing techniques are discussed. Parameter evaluation algorithms with flowcharts were developed for PV components. Consequently, web-based software was developed and simulated for a different case study. The results described the estimated load, average daily load, ratings of PV system components such as inverter, battery, solar panel, and charge controller. The cost estimates of each component, the total estimated cost of the project, and the specification of components’ purchasing store are similarly presented. Thus, the developed application can be applied to size different ranges of microgrid systems meant for several applications.

Drained agricultural landscapes under the impact of airborne industrial pollution

When assessing the ecological state of drained agricultural landscapes exposed to pollution, the average daily dust load, the chemical composition of the snow cover of the drained lands, the elemental composition of soils and the yield of perennial fodder grasses were determined. Snowfall, which is a good indicator of airborne technogenic fallouts, was classified as contaminated near the mining site, as opposed to the case of road traffic. Although the average daily dust load was very high the total level of chemical pollution near the quarry was low. Depending on the type of technogenic impact, the sequences of macro- and microelements accumulation in the snow cover were identified: quarry - Al > Mn > Mg > Ca > Fe, highway -Cr > Al > Mg > Pb > Ca > Co. Depending on the physical properties of the soils and technical features of the drainage network, Multidirectional trends in the inflow of pollutants into the upper horizons of the farmland soils with surface waters were noted. According to the results of this study, the yield of perennial fodder grasses increases with distance from the pollution sources under both types of technogenic influence.

Evaluation of the Needs of Ferry Boats on the Tanjung Kalian – Tanjung Api-Api Bangka Belitung Province

Tanjung Kalian Ferry Port is a ferry port that connects Sumatra Island and Bangka Island which has a distance of 30 miles. The Tanjung Kalian – Tanjung Api-Api route has 13 (thirteen) ships that operate for a travel time of 240 minutes or 4 hours. High productivity of passengers and vehicles on the Tanjung Kalian – Tanjung Api-Api route which causes the ship's carrying capacity to exceed the provided capacity, resulting in load accumulation. The method of analysis of the carrying capacity on the ship uses the analysis of the daily average load factor calculation. The primary data used is a survey of productivity data for departures and arrivals for 15 days from April 21 – May 5, 2021, survey data for ship sailing times, and survey data for ship layover time for the Tanjung Kalian – Tanjung Api-Api route. By looking at the increasing productivity of passengers and vehicles at the Tanjung Kalian Ferry Port, there is an increase in the needs of service users that must be met, including the frequency of ships and the number of ships operating. In accordance with the results of the analysis, Tanjung Kalian Ferry Port must increase the frequency of ships to 19 trips/day. This is used to overcome the number of service users who are not transported.

Power and Energy Rating Considerations in Integration of Flow Battery with Solar PV and Residential Load

Integration of renewable energy sources such as solar photovoltaic (PV) generation with variable power demand systems like residential electricity consumption requires the use of a high efficiency electrical energy system such as a battery. In the present study, such integration has been studied using vanadium redox flow battery (VRFB) as the energy storage system with specific focus on the sizing of the power and energy storage capacities of the system components. Experiments have been carried out with a seven-day simulated solar insolation and residential load characteristics using a 1 kW VRFB stack and variable amounts of electrolyte volume. Several scenarios have been simulated using power and energy scale factors. Battery response, in terms of its power, state of charge and efficiency, has been monitored in each run. Results show that the stack power rating should be based on peak charging characteristics while the volume of electrolyte should be based on the expected daily energy discharge through the battery. The PV source itself should be sized at about 25% more energy rating than the average daily load. The ability to design a VRFB with a high power-to-energy ratio makes it particularly attractive for PV-load integration.

Integrated modeling and feasibility analysis of a rooftop photovoltaic systems for an academic building in Bangladesh

Abstract This paper presents integrated modeling and feasibility analysis of a rooftop photovoltaic system (RPS) for an academic building in Bangladesh. The average daily load is 353.63 kWh/day, and the peak load demand for the studied region is 90.85 kW. Four different configurations of 46 kW, 64 kW, 91 kW and 238 kW photovoltaic (PV) systems are designed and compared based on the financial, sensitivity and environmental benefit analysis to find out the most optimized one. The total net present cost, cost of energy, internal rate of return and payback period for the 91 kW (most optimized) system are found to be $146 317, $0.0385, 120.3% and 8.3 years, respectively. Seven sensitivity variables are utilized to investigate the system’s performance due to the variation of input variables, ensuring that the optimized system is less vulnerable than others. Besides, the proposed RPS (91 kW) for the selected region reduces the CO2 emanation by 90 010 kg/year and has a negligible shading effect compared to the amount of electricity generation from it.

On-grid Photovoltaic Power System for Governmental Office Electrification

Solar energy is one of the most promising renewable energy sources. The potential solar energy has a capacity to meet all energy requirements for human survival on planet earth. Some applications such as a thermoelectric generator, electric power generation with the assistance of solar panels and water applications are required to reduce the demand for electricity generated by conventional power plants. The current work evaluates the effectiveness of solar energy for supplying the police building located in Diyala, Iraq. The installed renewable power system consists of photovoltaic/ battery system set with grid connection installed on the roof of the building with a capacity of 5.52 kWp and battery unit (200 A, 48 Volt). Based on the daily average load kWh and daily average solar irradiance for the selected site (4.3 kWh/m2), the results of the energy generated by the system for two selected days showed that for a sunny day is about (11.63 kWh) and for party cloudy day is about (8.02 kWh). The average of energy fed to the grid for a sunny day was recorded more by more than 3.0 kWh and for party cloudy day by more than 4.0 kWh. The system installed at the first day of February of the year 2021. The obtained results encourage to install of photovoltaic systems in the selected site which can feed such facilities with renewable energy and deliver energy to the grid.

Optimal Operation of Low-Capacity Heat Pump Systems for Residential Buildings through Thermal Energy Storage

The paper provides results from a hardware-in-the-loop experimental campaign on the operation of an air-source heat pump (HP) for heating a reference dwelling in Pisa, Italy. The system performances suffer from typical oversizing of heat emission devices and high water-supply temperature, resulting in HP inefficiencies, frequent on-off cycles, and relevant thermal losses on the hydronic loop. An experimentally validated HP model under different supply temperatures and part-load conditions is used to simulate the installation of a thermal storage between heat generator and emitters, in both series and parallel arrangements. Results relative to a typical residential apartment show that the presence of the thermal storage in series configuration ensures smoother heat pump operation and energy performance improvement. The number of daily on-off cycles can be reduced from 40 to 10, also saving one-third of electric energy with the same building loads. Preliminary guidelines are proposed for correctly sizing the tank in relation to the HP capacity and the average daily heating load of the building. A storage volume of about 70 L for each kilowatt of nominal heating capacity is suggested.