Solar Pumping System Research Articles

Sistemas de bombeo solar en Pachuca Hidalgo

The extraction of water from wells for supply in rural populations is one of the most profitable and novel applications of photovoltaic solar energy. The use of a specific type of submersible pumps for applications with photovoltaic energy, that work with direct / direct current (DC / DC) generated directly from the photovoltaic modules, allows an independent installation of the electrical network with very scarce maintenance needs, in This project was carried out the sizing, installation and commissioning of an autonomous pumping system with a submersible pump powered by a photovoltaic solar installation in the municipality of Actopan Hidalgo in the state of Pachuca. To implement the project, a climate study was first carried out. the area to support the efficiency of the solar pumping system, in this project we used 18 panels of 150 W, a SubDrive Solar controller, a Franklin Electric pump of 3 HP and a frequency inverter for the optimization of said pump.

The effect of temperature and light on strawberry production in a solar greenhouse

Strawberry production is greatly affected by environmental factors, especially temperature and light. A solar greenhouse with opaque photovoltaic (OPV) modules and a solar combined air source heat pump system was built for strawberry production. The aim of this study was to assess the impact of differences in both temperature and light factors caused by OPV modules and solar heating on strawberry growth and quality in a constructed greenhouse. The ‘Jingzangxiang’ strawberry was selected and planted in the greenhouse. The indoor temperature with the heating system was 5.3–7.3 °C higher than the ambient temperature at the coldest period in the city of Kunming. At noon, the chlorophyll content of the shaded strawberry plants was 1.3 times higher than that of the unshaded plants in sunny weather, and the average shaded photosynthetically active radiation (PAR) was 230 μmol·m−2·s−1 in the greenhouse, where 25.9% of the roof was covered with OPV modules. Under this shading treatment, the optimum light range of PAR for the ‘Jingzangxiang’ strawberry was 387–437 μmol·m−2·s−1, and the optimum temperature range during the daytime was 20.5–27.4 °C. The largest single strawberry fruit weighed 33.9 g, and the soluble solids content of the shaded strawberry fruit was 16.4%, which was higher than that of the unshaded strawberry samples. Furthermore, the yield of the shaded samples was 1.2 times that of the unshaded samples. In summary, strawberry plants shaded by OPV modules were superior to unshaded strawberry plants in terms of growth, quality and yield. This research provides experimental support and information on the optimal temperature and light ranges for the growth of the ‘Jingzangxiang’ strawberry in solar greenhouse.

Theoretical and experimental study of a novel solar indirect-expansion heat pump system employing mini channel PV/T and thermal panels

This paper presents the investigation of a novel mini channel PV/T and thermal collectors combined heat pump system, using both experimental and theoretical methods. Data were produced under conditions typical for winter days in Lvliang, China. A simulation model is developed to conduct theoretical evaluation based on real-world conditions. The experimental and simulated electrical and thermal efficiency of PV/T panels, thermal efficiency of thermal collectors and COP of heat pump are compared. It is shown that the experimental and simulated results are in close agreement. The errors range from 4.0% to 9.1%, giving us confidence that this model is reasonable to predict the seasonal performance of the system. The experimental and simulated results of the system provide fundamental data for performance analysis in winter conditions and inform further improvements of similar systems in the future.

Parallel vs series configurations in combined solar and heat pump systems: A control system analysis

This paper presents the modelling of two Solar Heat Pump systems, one for Domestic Hot Water and other one for Space Heating in two different configurations. Both system’s configurations can commute between parallel and series operation. The Configuration “A” uses a heat pump with two evaporators, allowing to work as an air source Heat Pump or as a water source Heat Pump. The Configuration “B” uses a heat exchanger to preheat the air entering to an air-to-water Heat Pump. These configurations are simulated in TRNSYS 17 for evaluating their performance in three Chilean cities: Santiago, Concepción and Puerto Montt. The control system applies a switching criterion between operation modes based primarily on the available solar irradiation. According to the results, the individual performance figures of the Heat Pump and of the Solar Collectors increase. Nonetheless, the results show that the Seasonal Performance Factor of the overall system decreases when it is switched from parallel to series. In the case of space heating, the Configuration A using evacuated tubes collectors shows a decrease of the Seasonal Performance Factor from 5.85 to 4.78 in Santiago, 5.35 to 4.30 for Concepción and 4.70 to 3.87 for Puerto Montt. In all case studies, unglazed collectors applications show a maximum SPF decrease of 0.04 and a maximum increase of 0.01. The results obtained can be influenced by the applied switching criterion used in this study, which does not force the Solar Collectors to increase their operational time by cooling them with the Heat Pump. Then, for the case studies, the non-inclusion of additional solar collector’s operational time leads to decrease the system performance.

Mathematical modeling of direct-coupled photovoltaic solar pump system for small-scale irrigation

ABSTRACTIn this paper, for the first time, modeling of a photovoltaic solar pump system integrated with a drip irrigation system is presented. There is some complexity in the adaption of the operating point of the pump and photovoltaic panel, especially when connect to the drip irrigation system. A mathematical model has been proposed in this paper to validate PV small-scale irrigation pump. The proposed model is a novel method that evaluates the solar pump size system driving a drip irrigation system. Based on the model, the designation process has three stages: solar power generation, electro pump, and drip irrigation network. A mathematical model was applied to each of the three stages and interconnected. The effect of the ambient temperature on pumped water from the source was determined hourly for the days of a year. In addition, the effect of the panel tilt angle on the amount of pumped water in different days of a year is presented. The number of emitters in a small-scale irrigation is influenced by the flow rate and the drop pressure of the emitter. The results show that the ambient temperature has a significant influence on the amount of discharge water from the pump.

EVALUATION OF SOLAR POWERED DRIP IRRIGATION SYSTEM SYSTEM

Egypt’s demand for electricity is growing rapidly and the need to develop alternative power resources is becoming ever more urgent. It is estimated that demand is increasing at a rate of 1,500 to 2,000 MW a year as a result of rapid urbanization and economic growth. Egypt is now struggling to meet its own energy needs. Egypt has been suffering severe power shortages and rolling blackouts over the past years, necessitating the requirement to look to alternative energy options. Energy demand is increasing fastly so as to meet the requirements of growing population in the world. This study aimed to compare between traditional energy and solar generators in terms of energy consumption and cost effectiveness. Pumping systems were used to operate units of drip irrigation for the crop which was planted, so as to determine the best and least expensive energy consumption under this system. The required hydraulic experiment and measurements were performed on a private farm at Beni Salama, Giza which lies at latitude 30.32°N, 30.80°E during 2016 and 2017. Measurements were done at two days randomly selected in the months of December and March. This study evaluated the average monthly measurements for December 2016 and March 2017 where onions were grown. Maximum and minimum for Pv system DC power output were 6398 and 5755 W, the maximum and minimum for AC current were 5814 and 5548 W, respectively. Maximum and minimum for hydraulic power were 5911 and 3553 W, respectively. Efficiency of both photovoltaic, inverter, pump and overall system were also calculated for these days. Maximum and minimum for module efficiency were 14% and 13.2%, respectively, and maximum and minimum for inverter efficiency were 95%, 89%, respectively. Maximum and minimum for pump efficiency were 64%, 54%, respectively. While for overall efficiency, they were 8% and 3%, respectively. The results showed that solar pumping system is a reliable system

Design of solar photovoltaic pressurized drip irrigation pumping system at al-salman district in samawa governorate

The seasonal climate changes have direct effects on determination of crop water requirement, irrigation scheduling and the potential of solar energy generation to operate the pumping system for watering crops. This research paper studied the technical evaluation of solar pumping and pressurized drip irrigation systems to investigate the recommended water required for suggested tomatoes crop in area of (one hectare) at AL-Salman district using measured climatic data from AL-Salman Agro-meteorological weather station for a period (2013-2017). The maximum average monthly of solar radiation was 7.6 kWh/m<sup>2 </sup>at June in all the years of recording data, while the minimum average monthly value was 3.37kWh/m<sup>2</sup> at December where the sun at lowest point across the sky. The annual average hours of peak sun that corresponds to the operation time of the pumping system at maximum water consumption was calculated at eight months from March to October with a value of 7.2 hours/day, while it was 5.2 hours/day during the other four months (January, February, November and December). The Solar pumping sizing based on H-Q performance curve of a maximum flow rate of 64.45 m3/h and pump capacity of 16.79 kW with compounds motor pump efficiency of 61.2%. The total water production was 230000 m³/per year which indicates compatible overall system design and adequate to irrigate more planting land with same or other crop types.

All-weather characteristic studies of a direct expansion solar integrated air source heat pump system based on PCMs

Solar integrated air source heat pump possesses competitive advantages of improving heating performance and capacity, particularly in cold region. However, the instability of solar energy is an obstacle for ensuring reliable operation of heat pump system. Selecting CaCl2·6H2O/Expanded Graphite (EG) composite phase change materials (PCMs) as the heating source of heat pump, improving it’s evaporation temperature, is an effective approach ensuring high-performance operation of the system in cold region. In this paper, a solar regenerator filled with PCMs and array heat pipe was developed, it is a compact device and behaves superior thermal efficiency. The all-weather characteristics of a direct expansion solar integrated air compound heat pump was studied. Based on different solar irradiation, the system operates in four patterns by combining or switching different evaporators: air source heat pump (ASHP); solar energy heat pump (SEHP); composite heat pump with combined (CCHP) or switched (CSHP) evaporators. The investigation results indicate that the performance of the other three patterns were improved variously compared to ASHP. The average COPs and exergy efficiency of SEHP were improved 70% and 67% respectively, a reduction of the time for heating water with temperature from 15 °C to 55 °C of about 50% was obtained. The economy of different heating schemes were investigated. The conclusions show that although the initial cost of the composite heat pump heating (CHPH) is high, CHPH effectively improve environmental protection and has short dynamic investment payback period, indicating that it is a feasible and alternative heating technology for cold and sunny region.

A high proportion of new energy access–combined cooling, heating, and power system planning method

Distributed generation (DG) technologies are environmentally friendly and have low operating costs, and thus, distributed generators are widely used for the energy supplies of buildings. Solar energy used for on-demand heating of buildings is also a mature technology that is environmentally friendly and inexpensive and has a short recycling life cycle. This paper proposes a high proportion of new energy access–combined cooling, heating, and power (HPNE-CCHP) system composed of a distributed generator and solar energy heat pump system. To obtain the optimum capacity of the HPNE-CCHP system, nondominated sorting genetic algorithm-II (NSGA-II) was used to optimize the system by considering the life cycle cost (LCC) and life cycle pollutant emissions (LCPE) as the objective functions. A mixed integer economic scheduling model (MIESM) was proposed to make the HPNE-CCHP system operate more economically. Finally, an HPNE-CCHP system was constructed for a building in Northern China. The simulation results show that an HPNE-CCHP system with a moderate proportion of new energy is more economical and environmentally friendly than a traditional CCHP system. Building occupants, depending on their desired spending, can select the best capacity configuration on the Pareto frontier. Although pollutant emissions will be reduced as the proportion of new energy increases, this type of configuration is expensive.

Numerical simulation and experimental validation of a micro-channel PV/T modules based direct-expansion solar heat pump system

This paper presents a novel solar driven direct-expansion heat pump system employing micro-channel PV/T modules as the evaporator. The system can provide both the electrical power and thermal energy used for space heating for buildings. Experimental work was carried out to investigate the performance of the system under real-life condition and numerical simulation work was carried out for the same condition as the experimentation using a two-dimensional model developed by the authors. This specialist simulation model contains energy balance calculation of individual models of components, i.e., models of the micro-channel PV/T module (evaporator), compressor, heat storage tank (condenser), electric expansion valve and testing room. The experimental and simulation results showed a good agreement each other, with the maximum error of 7.2% which is the temperature of refrigerant at the outlet of PV/T modules. The experimental average electrical, thermal and overall efficiencies of the PV/T module are 13.1%, 56.6% and 69.7%, respectively. While the simulated results are 13.7%, 55.0% and 68.7%, respectively. The average experimental and simulated COP of the system is 4.7 and 5.0, respectively. With the solar heat pump system providing energy for the room of 150 m2 in the real-life testing condition, the temperature of the room can remain at 18.5 °C which was high enough for the space heating. Comparison among the simulation and testing results indicated that the simulation model was reasonable for predicting the performance of the system and provided feasibility for analyzing the annual energy performance in the future.

Direct characterisation of the annual performance of solar thermal and heat pump systems using a six-day whole system test

Systems that provide space heating and domestic hot water are characterized by dynamic operating conditions. For a reliable evaluation of the general system performance, dynamic system test procedures are a more reliable, more reproducible and faster way than using steady-state component test results in combination with annual system simulation or others extrapolation schemes. However, the utilization of dynamic whole system testing was so far hindered by the cost and time associated with the laboratory measurements, and by a lack of scientifically justified procedures for the determination of suitable test profiles.This paper presents an analysis of the suitability of using a six-day sequence for the direct characterization of a solar and heat pump system. The new six-day sequence was developed to perform a benchmark test and its representativeness was verified with one-hundred different solar and heat pump system configurations.It was found that some independent variables lead to a predictable deviation in the performance evaluation based on the six-day sequence compared to whole-year figures, that can be greatly reduced by simple correction factors. For the different configurations, the correction factors reduced the standard deviation of the energetic performance results to 2.5%.

Economic analysis of solar and air energy systems for energy demand of space heating and domestic hot water of buildings

This study focuses on the economy of two renewable systems supplying the same demand of domestic hot water (DHW) and space heating (SH) for a city household located in Beijing of China. The systems are the solar thermal system and air source heat pump system. Both the two systems are considered for meeting the energy demand of SH and DHW. Optimized simulations are carried out to recognize the most economical configurations. The results show that, for a 15-year running time, the air source heat pump system comprising a 10 kW air source heat pump is the best configuration and has the minimum cost.

Monitoring the performances of a maximum power point tracking photovoltaic (MPPT PV) pumping system driven by a brushless direct current (BLDC) motor

Nowadays, water pumping systems powered by solar-cell generators are one of the most important applications. It’s a promising alternative to conventional electricity and diesel based pumping systems, especially for applications like community water supplies and irrigation. This study presents a monitored standalone photovoltaic solar direct pumping system using the Maximum Power Point Tracking (MPPT) algorithm to optimize the solar photovoltaic conversion efficiency. It was done at ISET-Rosso in Mauritania. The experimental setup based on Lorentz PS1200C-SJ8-5 pumping system consists of four photovoltaic (PV) panels, inverter PS1200, BLDC motor, centrifugal pump and a storage tank. The system has been monitored, in order to determine the relationship between: the DC power produced by the PV generator and the solar radiation; the water flow and the DC power and by then the relationship between the water flow and the solar radiation. The effect of ambient temperature and solar radiation on the PV panels was also done under Matlab/Simulink environment and compared to the experimental results. ©2019. CBIORE-IJRED. All rights reserved

Optimization of Solar Coupled Heat Pump System for Space Heating Application using Taguchi Method

In the recent couple of decades the demands for energy in India growing at a very high rate such a way that the conventional energy sources are not sufficient to meet the demand. At present most of the energy demand is met by fossil fuels, however, renewable energy sources such as solar energy, wind energy, biomass energy etc. have also been harnessed to some extent. The energy usage can be broadly classified to different purpose such as, building sector, industries, transport and household purpose. Among these one third of the total energy consumed in the world is spent for heating/cooling applications. It is to be noted that most of the heating/cooling demand are met by conventional system. This research work proposes a methodology for energy efficient space heating technique using solar coupled heat pump (SCHP) system under Indian climatic conditions by optimizing the COP of SCHP system and efficiency of solar collector using Taguchi technique. For the five influencing operating parameters of the system with three levels, an orthogonal array of L27 (35) has been selected using higher the better concept for 1 ton heating load capacity of the system during the winter season. Based on the 27 experimental trial runs it is found that the efficiency of solar collector and COP of the SCHP system varies from 38.8 % to 61.87 % and 1.9 to 3.01, respectively. The implementation of Taguchi method has resulted in 5.7% and 4.3% increase in solar collector efficiency and COP of SCHP system respectively.

Effect of seasonal variation on the performance of solar photovoltaic pumping system under field conditions

The present study was undertaken to analyse the performance of solar photovoltaic (SPV) pumping system parameters, under different seasons. The average flow rate in summer, monsoon, post-monsoon and winter season was 3.0, 2.17, 3.44 and 2.93 Lps, respectively. The average conversion efficiency in summer, monsoon, post-monsoon and winter season was 14.36, 15.13, 17.04 and 16.85%, respectively. The range of optimum panel temperature should be between 12–32°C at which conversion efficiency will be maximum varying from 18.39–21%. During smog the average solar irradiance and flow rate decreased from 828 W/m2 to 393 W/m2 and 3.09 Lps to 1.59 Lps, respectively, as compared to before smog conditions. The presence of clouds significantly affected/lowered down the current, RPM and flow rate but the temperature did not change much which reveals that temperature has minimum effect on the development of current and voltage in solar photovoltaic cells.

Performance improvement of solar photovoltaic/thermal heat pump system in winter by employing vapor injection cycle

Direct-expansion solar assisted heat pump (DX-SAHP) is a promising technology for saving energy. In this paper, vapor injection (VI) cycle system to DX-SAHP system is studied. Thermodynamic comparative analyses of ideal VI cycle and ideal conventional vapor compression cycle was carried out for verifying the advantages by applying VI cycle into DX-SAHP. Additionally, photovoltaic/thermal (PVT) modules were used in the system to harvest thermal energy and electric power. A PVT based solar heat pump system employing VI cycle (PVT-VISHP) was proposed, fabricated and investigated experimentally. Performance of the experimental prototype was subsequently evaluated for seven days in winter. The system’s performance was evaluated based on the average ambient temperature of −1.13 °C and solar irradiation of 164.03 W/m2. Results showed that the total generated electricity, heat, and consumed power of the system were 0.51 kWh, 23.68 kWh, and 7.24 kWh, respectively. Moreover, average heating coefficient of performance (COPth) and advanced coefficient of performance (COPPVT) of the PVT-VISHP system were 3.27 and 3.45, respectively. In the study, the ambient-evaporating temperature difference ranged from 9.2 °C to 17.1 °C. Furthermore, variations of injected vapor’s pressure, mass flow rate, mass flow rate ratio, and subcooling effects were analyzed in detail. Performance of the PVT modules during a sunny day was tested. It was found that the PVT modules’ average thermal collecting and PV efficiencies were 49.9% and 7.51%, respectively.

PERFORMANCE EVALUATION OF A SMALL AC/DC SOLAR WATER PUMPING SYSTEM FOR ROOF CULTIVATION

Solar water pumping for irrigation and drinking purposes is considered one of themost recently power system needed. The most important usage of solar pumping systems is to irrigatethe agricultural lands to help farmers instead of using electrical or fuel system that take a lot of time,high cost, effort and much losses. In this research, the performance evaluation of a mini water pump (5Watt) powered by small solar photovoltaic (PV) panel (10 Watt) was investigated to supply the neededwater for irrigating roof cultivation units. The experiments were carried out at Faculty of Agriculture,Zagazig University, Sharkia Governorate, Egypt (Latitude 30.5o – Longitude 31.5o) in winter andsummer seasons of 2018. Two solar pumping systems were evaluated; DC solar pumping system(DSPS) and AC solar pumping system (ASPS) under different operating parameters of PV panel tiltangles (15o, 30o, 45o, 60o and 75o), solar radiation hours during daylight (9:00 to 15:00) and pumpingheads (0 ,0.5, 1 and 1.5 m). All parameters were evaluated by determinations of pumping discharge,hydraulic energy, pump efficiency and cost. The obtained results revealed that, the best PV panel tiltangle for Zagazig region was 45o and 30o in winter and summer, respectively. Discharges andpumping efficiencies of ASPS were higher than DSPS. The optimum pumping conditions were 0.25and 1 m of pumping heads with 220 l/hr., and (83 l/hr., for winter, 88 l/hr., for summer) of pumpingdischarge for ASPS and DSPS, respectively. Pumping costs of one cubic meter of water by DSPS atpumping heads of 0, 0.5, 1 and 1.5 m were (0.16, 0.17, 0.19 and 0.21 LE) and (0.15, 0.17, 0.19 and0.21 LE), during winter and summer seasons, respectively. While pumping costs of one cubic meter ofwater using ASPS were about 0.22, 0.45, 1.23 and 7.11 LE/m3 at the same heads, respectively. So, asmall size of solar PV power system can be efficiently supply irrigation water for roof cultivation units.

Research on real-time integrated control method of PV-SHAPWH

The real-time operation control of the photovoltaic integrated solar-assisted heat pump water heater (PV-SAHPWH) can improve the system's annual performance. In this paper, the real-time variable capacity control and starting time control of photovoltaic integrated solar heat pump are simulated and experimentally researched. A real-time integrated control system is developed to achieve the hot water task in a predetermined time, reduce energy consumption and increase the net power generation of the system. A mathematical model of photovoltaic integrated solar heat pump system was established, and a photovoltaic integrated solar heat pump experimental prototype with a 4.32 m2 heat collecting area, a R22 working fluid compressor and a 150 L thermal water tank was built in Nanjing. The simulation program verified by the fixed-frequency operation test is used to construct the system running performance database and obtain the control strategy table, and adjust the system starting time according to the weather condition forecast of the day. In the real-time variable capacity test, the inverter compressor adjusts the system capacity, and the electronic expansion valve controls the evaporator outlet superheat to realize real-time variable capacity control. The research results show that the performance coefficient and photovoltaic power generation of the real-time integrated control heat pump system are improved compared to the simulation results of other control methods, and the hot water task can be completed accurately within the predetermined time.

Experimental Study of a Photovoltaic Direct Current Water Pumping System for Irrigation in Rural-Isolated Region of Arequipa, Peru

In the present experimental study, a photovoltaic (PV)-powered system in continuous current (4 kW) for the pumping of water in an isolated, rural agricultural zone in Arequipa—Peru was analyzed. A meteorological station was installed in the studied zone, measuring solar radiation, temperature, relative humidity, and wind speed. The electrical and hydraulic parameters of the solar-pumping system (i.e., electric current, voltage, mass flow, and hydraulic pressure) were measured in order to evaluate the efficiency of the energy transformation processes. The results indicate that, during the year of 2017, the PV pumping system in direct current (DC) functions from 07 h 30 min to 15 h 30 min, during an average of 8 h a day. The PV array, hydraulic, and global efficiencies were evaluated. This allows for the interpretation of efficiency independent of solar irradiance. The efficiency of the PV array and global efficiency remained constant (11.5% f and 8.5%, respectively). The functioning interval of the PV array ranges from 880 W up to 3400 W, making evident the versatility of the system of generation and consumption in DC, which is able to function since solar irradiance is at least 200 W/m2, corresponding to 880 W of PV array power, 27 m of total dynamic head (TDH) and 2 kg/s of mass flow, and 70% hydraulic efficiency. With greater mass flows (6.3 kg/s), the PV array power was 3256 W with a hydraulic efficiency of 55%, a TDH of 30 m, and a peak solar irradiance of 1190 W/m2. When the whole system functions in DC, the efficiencies are superior to those of systems, which operate with DC/alternating current (AC) current inverters.

Agricultural technology assessment for smallholder farms: An analysis using a farm simulation model (FARMSIM)

Previous models used to evaluate the adoption of agricultural technologies have focused mainly on assessing the ex-post impact of technology without necessarily quantifying the profit and risk associated with the adoption of technology. This study introduces a farm simulation model (FARMSIM) that evaluates the potential economic and nutritional impacts of new agricultural technologies before and after they are adopted (ex-ante and ex-post). FARMSIM is a Monte Carlo simulation model that simultaneously evaluates a baseline and an alternative farming technology for a representative farm. The farming technologies under study comprise water lifting technologies (pulley and tank, rope and washer pump, gasoline/diesel motor pump and a solar pump) and fertilizers. The study finds that the use of fertilizers combined with optimal irrigation to grow vegetables and fodder using a motor pump had the highest net present value and profit compared to other scenarios. However, the findings also indicate the scenario under the pulley system, a low cost technology, to be the most feasible with the highest benefit cost ratio. Solar pump system had a lower benefit cost ratio compared to the pulley and motor pump scenarios due to high initial investment cost. Based on simulation results, all four water lifting technologies are profitable and suitable for use in Robit kebele. Moreover, due to improved technologies in alternative scenarios, the nutrition simulation results show in general an increase in food quantities available to the family for calories, proteins, iron, fat, calcium and vitamin A. The daily minimum requirements per adult equivalent were met for all nutrients under study except for fat and calcium. Supplemental nutrition through production and purchase, to fill the gap in fat and calcium is recommended for households in Robit kebele.