Effect Of Storage System Research Articles

Operation of energy hubs with storage systems, solar, wind and biomass units connected to demand response aggregators

• Day-ahead scheduling has been carried out for energy hub. • Uncertainties of demands, PV, solar heat, wind and electricity prices are considered. • Demand response aggregator has been used as an input source of electricity. • Demand response effect on EH operation cost has been investigated. • Effect of storage systems on hub operation costs have been evaluated. Energy Hubs (EHs) play an important role in sustainable cities; they are multi-carrier energy systems that can satisfy different energy needs of consumers by relying on the conversion and storage of energy sources as well as renewable energy sources. With efficient and reliable energy supply, EHs may significantly contribute in developments of sustainable cities. In this paper, day-ahead scheduling of EHs is done, while they are connected to demand response aggregators. The studied EH includes photovoltaic and wind renewable sources, biomass, hydrogen electrolyzer, combined heat and power unit, solar heater, boiler, electric, thermal and hydrogen storage systems. Besides electric grid and gas network as input sources, EH may purchase electricity from demand response aggregators. Information gap decision theory (IGDT) is employed as a risk-aware method to handle uncertainties of electric, thermal and hydrogen demands, photovoltaic and wind power, solar heat and electricity prices. The scheduling is carried out from the perspective of the uncertainty free, risk-averse and risk- seeking decision-makers. The problem is formulated as a mixed-integer model and is solved using CPLEX solver in General algebraic modeling system (GAMS). The impact of risk awareness and deviation factors of critical and target costs on day-ahead scheduling and EH operation costs is investigated. The results show that the transaction with demand response aggregator decreases EH operation cost by 20.1%. The results also show that electric, thermal and hydron storage systems respectively decrease the operation cost by 3, 1.7 and 2.1%.

Effect of Storage System and Packages Type on The Self life and Quality of okra

Effect of Storage System and Packages Type on The Self life and Quality of okra

Scheduling heat and power microgrids with storage systems, photovoltaic, wind, geothermal power units and solar heaters

Combined heat and power (CHP) microgrids (MGs) are a set of CHP units, boilers, power-only distributed generation (DG) units and storage systems that simultaneously supply heat and power demand. In this research, the objective is to provide a comprehensive mixed integer linear programming (MILP) model for unit commitment (UC) in CHP MGs including fossil-fueled power-only DGs, boilers, CHP units, photovoltaic, wind and geothermal power units, solar heater, battery charging station (BCS), adjustable thermal loads, battery energy storage (BES) and thermal energy storage (TES) units. In the proposed model, all operational constraints of CHP units, boilers and power-only units such as minimum up/down time and start-up/ shut-down ramp rate limits are considered and the commitment history of generation units prior to operation horizon is considered. In the proposed model, type II CHPs with non-convex feasible operating region (FOR) are used and their non-convex FOR is transformed into two convex FORs. The proposed model is solved with CPLEX solver in general algebraic modeling system (GAMS) which guarantees the achievement of the global optimum. The model is solved for different scenarios wherein the effect of BCS, effect of storage systems as well as the effect of adjustability of loads on MG operation is investigated. According to the results, BES and TES respectively decrease MG operation cost by 7.4% and 1.82%.and BCS adds 20.19% to the MG operation cost. The results also show that with replacement of adjustable thermal loads with evenly distributed loads, MG operation cost increases by 0.6%.

A case study on the effect of storage systems on a distribution network enhanced by high-capacity photovoltaic systems

Modern distribution networks with intermittent weather-dependent renewable energy resources may require energy storage to smooth out intermittency in their power generation and balance energy production and demand. Therefore, the objective of this study is to present a case study of analyzing the effect of such storage systems (SSs) on a distribution network enhanced by high-capacity photovoltaic (PV) systems. For this purpose, this study defines two metrics that quantify the effect of SSs on peak load reduction, power, and voltage such as a load factor and a change in total power generation. Then a well-known strategy that charges storage at night and discharges it to distribution networks at peak demand times is modeled in steady-state power systems analysis software, or OpenDSS. Next, as a case study, this study modifies the IEEE 37-bus test feeder enhanced by four photovoltaic systems (PVSs) with a capacity of 15 and 30 percent of total peak power, adds SSs with the same capacity as PVSs and a duration of three hours to the test feeder, and calculates steady-state power flow in 15-min intervals during a week. Finally, it presents the effect of SSs from the following point of views: (a) a reduction in peak load, (b) an increase in over-voltage (e.g., 1.05 p.u.), and (c) intermittency in voltage and total power generation.

An efficient cloud storage system for tele-health services

Healthcare service is a critical aspect of our daily lives. Enabled by technologies such as wearable devices and wireless sensor networks, tele-health has becoming a promising new field in IT industry. Wearable devices, which detect real-time human body conditions, form body sensor networks (BSNs) for patients. In a cloud-enabled tele-health ecosystem, health data are collected by the BSN and sent to mobile devices such as smart phones and tablets. These embedded devices process the data and forward them to remote data centers. Due to the energy and time constraints of embedded systems, the effectiveness of storage systems become a critical issue. For years, memory technologies such as SRAMs and DRAMs have been widely used in computer systems. SRAMs are fast while DRAMs have high density. However, SRAMs have the disadvantage of power leakage and low density. DRAMs are slower in read and write operations. New memory technology for embedded tele-health is needed. In the paper, we propose a hybrid memory system for embedded tele-health. We combine phase-change memory PCM with flash memory to meet energy and latency requirement while reducing capital expenditure. Moreover, the data allocation and storage on server side is also a challenging problem in tele-health. Effective storage system designs are desired to efficiently store and manage health care data from users. Therefore, in the paper, we design a ecosystem for tele-health including the memory storage for embedded devices and data storage for tele-health data centers. To fully utilize the proposed ecosystem, we design several resource allocation algorithms with dynamic programming and heuristics. The experiments show that our approaches can achieve up to 30% performance enhancement compared to greedy approaches.

Assessment of Operating Condition Dependent Reliability Indices in Microgrids

Reliability results are important for proper planning and operation of utility companies. At the base of this method of analysis is the failure rate of the system components. In the traditional method, this probability of failure is determined by the components’ manufacturer and is considered to be constant. This study proposes a dynamic modeling of failure rate, taking the system operating conditions into consideration. With this new consideration, an IEEE test system has seven of its reliability indices quantified for comparison. The inclusion of the newly modeled failure rate leads to a worsening of 11.07% in the indices, on average. A second analysis is performed considering the presence of DG sources within the microgrid, namely PV and wind based. An improvement of 0.71% on the indices is noticed, once the DG sources are introduced. Finally, the effects of storage systems in the microgrid are investigated through a third scenario, in which two 2 MWh battery systems are introduced, and an improvement of 3.05% is noticed in the reliability indices.

Effect of storage system and tarpaulin color on nutritional quality and digestibility of stored lucerne hay in the irrigated Sonoran Desert

A field trial and a steer digestion trial were conducted to evaluate the effect of tarpaulin color on the quality and digestive attributes of lucerne ( Medicago sativa) hay during a 20 week summer storage period in the irrigated Sonoran Desert of northwestern Mexico and the southwestern US. Lucerne hay was subjected to six treatments (four repetitions per treatment): stored roadside uncovered (UC), stored roadside and covered with a white plastic tarpaulin (WT), stored roadside and covered with a black plastic tarpaulin (BT), stored roadside and covered with a silver-colored plastic tarpaulin (ST), stored outside under a plastic hay barn (BC), and stored in an air-conditioned room (AC). During the 20 week storage period, daily maximum temperatures exceeded 38 °C for more than 16 weeks. Internal bale temperatures were 44.9, 44.1, 43, 42.9, and 40.7 °C for BT, UC, ST, WT, and BC, respectively, during the storage period. UC, WT, BT, and ST, at the end of the field trial, were heat damaged as indicated by an acid detergent insoluble nitrogen/nitrogen ratio greater than 0.14. BT bales had the greatest (P<0.05) heat damage of all treated hay. Total tract dry matter (DM) digestible contents were 668.0, 644.8, 651.5, 597.7, and 562.0 g/kg DM for BC, WT, ST, UC, and BT, respectively. Total tract crude protein (CP) digestible contents were 796.6, 786.2, 773.7, 720.8, and 71.90 g/kg CP for BC, WT, ST, UC, and BT, respectively. The authors concluded that valuable hay products, such as lucerne, should be protected from harsh environmental extremes during storage in hot desert climates. Protecting lucerne with a roof structure (BC) provided the best protection against the heat. Covering the hay with tarpaulins is another viable option, but not all tarpaulin colors are equally efficient. BT did no better than the negative control (UC). The white tarpaulin (WT) did a satisfactory job in protecting lucerne against the heat in comparison to BT and ST. Valuable hay products, such as lucerne, if stored during the summer in hot desert climates, should include an acid detergent insoluble nitrogen analysis to detect the presence of heat damage.

Effect of storage system and sprout removal on post-harvest yam (Dioscorea spp.) fresh weight losses

Two aspects of yam storage practice were tested from 1994 to 1995 in central Côte d'Ivoire. The first experiment compared the storage environment in pits or sheds with that of the traditional yam open barn method. The pits allowed the daily range of variation in temperature to be reduced while maintaining a high relative humidity (RH), whereas the temperature and RH in the sheds were similar to those of the yam barns. Differences in temperature and RH between the storage systems had little effect on the fresh weight losses of the tubers. The more effective protection against solar radiation and rain afforded by the sheds and pits reduced fresh weight losses in D. cayenensis rotundata by 12% over 6·5 months in comparison with the barns. The second experiment tested the regular removal of the sprouts. Sprout removal reduced fresh weight losses equally over 5 and 6 months' storage. The reduction in fresh weight loss was 12% for cv. Gnan (D. cayenensis rotundata) during 6 months' storage. Monthly sprout removal gave an equal benefit in pits, in sheds and on yam barns. The monthly cutting of sprouts at the base should be encouraged in places where this is not already done. The total loss is mainly determined by the growth of the sprouts and the reduction in weight after onset of sprouting, which are highly dependent on species and cultivar. Bètè bètè yams had better keeping qualities than all the other cultivars tested.

Effect of Storage System and Dry Matter Content on the Composition of Alfalfa Silage

The objectives of this study were to evaluate the effects of dry matter (DM) content and three different storage systems on the quality of alfalfa ensiled on commercial farms. Alfalfa silage samples were collected from 21 bunker silos, 20 silos that limited oxygen infiltration, and 19 tower silos on 43 commercial dairy farms. Storage system and DM content were confounded because silages from bunker silos generally were wetter than silages from O2-limiting and tower silos. There was no effect of storage system on crude protein content of the silages. However, silage from bunker silos had higher concentrations of nonprotein N, NH3 N, and acid detergent insoluble N than did silages from the other two storage systems. The proportion of total N in neutral detergent insoluble N minus acid detergent insoluble N was greatest in silage from O2-limiting silos. Fiber components were affected by storage system; silage from bunker silos had the greatest concentration of acid detergent fiber and neutral detergent fiber. Concentrations of acid detergent fiber and neutral detergent fiber were higher in wetter silages from bunker silos, but DM content did not influence fiber content of silages from O2-limiting and tower silos. Concentrations of total organic acids, acetic acid, and butyric acid were highest in silages from bunker silos. The general effects of DM on the quality of silages obtained from commercial dairy farms were similar to results obtained from laboratory-scale silos.

Effects of Storage System on the Chemical Character and Utilization of Sorghum Grain by Steers

Effects of Storage System on the Chemical Character and Utilization of Sorghum Grain by Steers