Feasibility study of photovoltaic technology in Qatar

This study presents a comparative economic analysis of electricity generation using photovoltaic (PV) cells and conventional gas turbines. The generation cost per kWh was estimated for the two systems. The energy generated by PV cells was estimated using weather data for Qatar. A sensitivity analysis was carried out on some factors: installation capital cost, conversion efficiency and discount rate. The study indicates that, at the present time, PV stations are not economically feasible in Qatar compared with conventional gas turbine stations.     

Optimal design and development of PV-wind-battery based nano-grid system: A field-on-laboratory demonstration

The present paper has disseminated the design approach, project implementation, and economics of a nano-grid system. The deployment of the system is envisioned to acculturate the renewable technology into Indian society by field-on-laboratory demonstration (FOLD) and “bridge the gaps between research, development, and implementation.” The system consists of a solar photovoltaic (PV) (2.4 kWp), a wind turbine (3.2 kWp), and a battery bank (400 Ah). Initially, a prefeasibility study is conducted using the well-established HOMER (hybrid optimization model for electric renewable) software developed by the National Renewable Energy Laboratory (NREL), USA. The feasibility study indicates that the optimal capacity for the nano-grid system consists of a 2.16 kWp solar PV, a 3 kWp wind turbine, a 1.44 kW inverter, and a 24 kWh battery bank. The total net present cost (TNPC) and cost of energy (COE) of the system are US$20789.85 and US$0.673/kWh, respectively. However, the hybrid system consisting of a 2.4 kWp of solar PV, a 3.2 kWp of wind turbine, a 3 kVA of inverter, and a 400 Ah of battery bank has been installed due to unavailability of system components of desired values and to enhance the reliability of the system. The TNPC and COE of the system installed are found to be US$20073.63 and US$0.635/kWh, respectively and both costs are largely influenced by battery cost. Besides, this paper has illustrated the installation details of each component as well as of the system. Moreover, it has discussed the detailed cost breakup of the system. Furthermore, the performance of the system has been investigated and validated with the simulation results. It is observed that the power generated from the PV system is quite significant and is almost uniform over the year. Contrary to this, a trivial wind velocity prevails over the year apart from the month of April, May, and June, so does the power yield. This research demonstration provides a pathway for future planning of scaled-up hybrid energy systems or microgrid in this region of India or regions of similar topography.     

Economic feasibility of campus-wide photovoltaic systems in New England

Compared to the national average residential retail electricity price, Connecticut (CT) had the 4th highest electricity price in the country with 19.23 cents/kWh in September 2015, nearly 50% higher than the national average for price of electricity. This study aims to assess the economic feasibility of the solar PV systems at the campus under realistic constraints, by analyzing actual data from the solar array on campus. The project focused on the economic feasibility of solar PV systems on campus with physical, spatial, and practical constraints that result in a project to deviate from theoretical (estimated) values. To achieve that, the prediction of the PV power generation from the building was developed and compared with the actual (measured) data.The average payback period of a campus-wide PV system was calculated as primarily 11 years, within a range of 8–12 years, and was estimated to reduce overall building operating expenses by $250,000, or 8%. The economic parameters such as NPV and IRR also validated the investment worthiness. The results of the study could be used to analyze or further develop feasibility studies of PV systems at other universities in Connecticut and neighboring states that share similar climatic characteristics and economic factors.     

Return on capital and earned carbon credit by hybrid solar Photovoltaic—wind turbine generators

This paper presents a methodology to optimise a hybrid solar Photovoltaic—wind turbine generator for the villages situated in the remote areas, especially coastal regions of India. Owing to good insolation and wind density, the hybrid system composed of 6 photovoltaic (PV) modules, one wind turbine and 3 batteries are sufficient to fulfil all the necessary power demand without interruption for an Indian village. The analytical analysis shows that the system having lifespan of 30 years has return on capital, cost of power produced and cost of the hybrid solar-wind generators as 4.08%, € 0.155/kWh and € 4723.5/kWh respectively. The energy payback time is 2.47 years and will lead to earn € 28.52 every year of carbon credits.     

Off-grid hybrid renewable energy system with hydrogen storage for South African rural community health clinic

Most inhabitants of rural communities in Africa lack access to clean and reliable electricity. This has deprived the rural dwellers access to modern healthcare delivery. In this paper, an off-grid renewable energy system consisting of solar PV and wind turbine with hydrogen storage scheme has been explored to meet the electrical energy demands of a health clinic. The health clinic proposed is a group II with 10 beds located in a typical village in South Africa. First, the wind and solar energy resources of the village were analysed. Thereafter, the microgrid architecture that would meet the energy demand of the clinic (18.67 kWh/day) was determined. Some of the key results reveal that the average annual wind speed at 60 m anemometer height and solar irradiation of the village are 7.9 m/s and 4.779 kWh/m²/day, respectively. The required architecture for the clinic composes of 40 kW solar PV system, 3 numbers of 10 kW wind turbines, 8.6 kW fuel cell, 25 kW electrolyser and 40 kg hydrogen tank capacity. The capital cost of the microgrid was found to be $177,600 with a net present cost of $206,323. The levelised cost of energy of the system was determined to be 2.34 $/kWh. The project has a breakeven grid extension distance of 8.81 km. Since this distance is less than the nearest grid extension distance of 21.35 km, it is established that the proposed renewable energy microgrid with a hydrogen storage system is a viable option for the rural community health clinic.     

Techno-economic evaluation of a grid-connected PV-trigeneration-hydrogen production hybrid system on a university campus

Many universities have plans to reduce campus energy consumption with developed energy efficiency strategies, supply the energy needs of the university campus with renewable energy and create a green campus. In order to serve this purpose, this study focuses on the simulation of the installation of an on-grid photovoltaic (PV) power system at the Vocational Colleges Campus, Hitit University. On the other hand, the integration of the simulated PV system with a gas fired-trigeneration system is discussed. Moreover, the study explores opportunities for solar hydrogen generation without energy storage on campus. For the PV system simulation, three different scenarios were created by using web-based PV system design software (HelioScope). Installed powers in the simulation were found as 94.2 kWe, 123.9 kWe, and 157.5 kWe for the low scenario (on the rooftop), high scenario (on the rooftop), and the high + PV canopy arrays scenario (on the rooftop and an outdoor parking area), respectively. The levelized cost of electricity (LCOE) values were 0.061 $/kWh, 0.065 $/kWh, and 0.063 $/kWh for the low scenario, high scenario, and the scenario including PV canopy, respectively. The energy payback time is found to be 6.47–6.94 years for the 20–25 years lifetime of the PV plant. The simulation results showed that the PV system could support it by generating additional electrical energy up to 25% of the existing system. The campus can reduce GHG emissions of 1546–2272 tonnes-CO₂eq, which is equivalent to 142–209 ha of forest-absorbing carbon unused during the life of the PV system. Depending on the production and consumption methods utilized on campus, which is a location with relatively large solar potential, the levelized cost of hydrogen (LCOH) of hydrogen generation ranged from 0.054 $/kWhH₂ (1.78 $/kgH₂) to 0.103 $/kWhH₂ (3.4 $/kgH₂). Consequently, with proper planning and design, a grid-connected PV-trigeneration-hydrogen generation hybrid system on a university campus may operate successfully.     

Cost and sensitivity analysis for photovoltaic station in Kuwait

A full analysis is shown in this paper for the cost of kWh generated from photovoltaic station located in Kuwait. By using a 21 years weather data for Kuwait, the yearly generated energy was found by proposing the PV station capacity with known panels tilt angle. The cost of kWh generated from PV station was compared with the kWh generated from conventional units in the country. A sensitivity analysis was done to some factors; capital cost per installed PV peak watt, discount rate, and operating peak hours, which affect the cost of kWh production from both PV and conventional units. If the PV station is proposed to be installed in Kuwait, the capital cost per PV installed peak watt must be less than today's prices.     

Electricity generation cost between proposed photovoltaic station and conventional units in Kuwait

A full analysis is shown in this paper for the cost of kWh generated from a photovoltaic station located in Kuwait. By using 21 years of weather data for Kuwait, the yearly generated energy was found by proposing the PV station capacity with known panel tilt angle. The cost of kWh generated from the PV station was compared with the kWh generated from conventional units in the country. A sensitivity analysis was done to some factors: capital cost per installed PV peak watt, discount rate, and operating peak hours, which affect the cost of kWh production from both PV and conventional units. If the PV station is proposed to be installed in Kuwait, the capital cost per PV installed peak watt must be less than today's prices.     

高效新型220 MW亚临界汽轮机优化选型分析

以越南某2×220 MW火力发电厂工程的设计、采购、施工(EPC )合同要求为出发点,从技术、能耗方面进行分析,根据国内200 MW等级超高压汽轮机和300 MW等级亚临界汽轮机的特点,通过分析比较两者的差别,提出了220 MW等级汽轮机可采用亚临界参数方案,通过优化叶片型式,减少轴封漏气,提高汽轮机汽缸效率,汽轮机热耗降低至8 026 kJ/kWh,并最终在工程中顺利实施。机组投运后,每年可节约10 161.5 t标煤,提高了机组的经济性,创造了较大的经济效益,可为后续同类项目的汽轮机选型提供参考。     

Economic evaluation of small-scale photovoltaic hybrid systems for mini-grid applications in far north Cameroon

A comparison between photovoltaic hybrid systems (PVHS), standalone photovoltaic (PV) and standalone diesel generator options is performed using the net present value (NPV) technique. A typical village mini-grid energy demand of 7.08 kWh/day is considered in the computation of energy costs and breakeven grid distances. A first sensitivity analysis is conducted using remote diesel prices of 0.8 €/l, 0.98 €/l, 1.12 €/l, 1.28 €/l with a PV module cost of 7.5 €/Wp. A second sensitivity analysis is also done using PV module costs of 5.25 €/Wp, 6 €/Wp, 6.75 €/Wp, 7.5 €/Wp with a diesel price of 1.12 €/l. The energy cost for the diesel option was found to be 0.812 €/kWh at a diesel fuel price of 1.12 €/l. The sensitivity analyses showed that minimum energy costs were attained in PVHS at renewable energy fractions in the range 82.6–95.3%. In the second sensitivity analysis the energy costs and breakeven grid distances were found to be in the ranges 0.692–0.785 €/kWh and 5.1–5.9 km respectively. For a PV module cost of 5.25 €/Wp, the lowest energy cost for the PVHS option was 0.692 €/kWh at a final renewable energy fraction of 95.3% with the diesel generator hours being 37 h compared to 2075 h in the standalone diesel generator option. Consequently, a 30% reduction in custom duties and taxes on imported PV modules and sub-systems would increase the use of small-scale and climate friendly PV mini-grids in remote areas of far north Cameroon that have an annual insolation of at least 5.55 kWh/m²/day.     

Grid electrification challenges, photovoltaic electrification progress and energy sustainability in Lesotho

Lesotho's energy profile is characterized by a predominance of traditional biomass energy to meet the energy needs of the rural households and a heavy dependence on imported petroleum for the modern economic sector needs. As a result, the country faces challenges related to unsustainable use of traditional forms of biomass and exposure to high and unstable oil import prices. There are relatively abundant renewable energy resources in the form of hydro, solar and wind. The average daily solar radiation in Lesotho varies between 4.5 and 6.5 kWh/m², with some areas in the South West averaging over 7 kWh/m²/day. Under the UNDP/GEF-supported Lesotho Renewable Energy-Based Rural Electrification (LREBRE) Project, a total of 5000 solar home systems (SHS) will be installed by 2012. Since the start of the project, a total of 1537 SHS with a capacity of 65 W have been installed, and an estimated 500 SHS have also been independently installed as a result of the project's influence. This paper examines the role of PV technologies in the sustainable development process, with particular reference to UNDP/GEF-LREBRE Lesotho PV project, and the extent to which this project is impacting on the PV industry. The paper also analyses national grid electrification and energy provision in rural areas and shows that the problem of rural electrification could be tackled by conventional and non-conventional means.     

Simulation of off-grid generation options for remote villages in Cameroon

Off-grid generation options have been simulated for remote villages in Cameroon using a load of 110 kWh/day and 12 kWp. The energy costs of proposed options were simulated using HOMER, a typical village load profile, the solar resource of Garoua and the flow of river Mungo. For a 40% increase in the cost of imported power system components, the cost of energy was found to be 0.296 €/kWh for a micro-hydro hybrid system comprising a 14 kW micro-hydro generator, a 15 kW LPG generator and 36 kWh of battery storage. The cost of energy for photovoltaic (PV) hybrid systems made up of an 18 kWp PV generator, a 15 kW LPG generator and 72 kWh of battery storage was also found to be 0.576 €/kWh for remote petrol price of 1 €/l and LPG price of 0.70 €/m³. The micro-hydro hybrid system proved to be the cheapest option for villages located in the southern parts of Cameroon with a flow rate of at least 200l/s, while the PV hybrid system was the cheapest option for villages in the northern parts of Cameroon with an insolation level of at least 5.55 kWh/m²/day. For a single-wire grid extension cost of 5000 €/km, operation and maintenance costs of 125 €/yr/km and a local grid power price of 0.1 €/kWh, the breakeven grid extension distances were found to be 15.4 km for micro-hydro/LPG generator systems and 37.4 km for PV/LPG generator systems respectively. These results could be used in Cameroon's National Energy Action Plan for the provision of energy services in the key sectors involved in the fight against poverty.     

Economic evaluation of a stand-alone residential photovoltaic power system in Bangladesh

The economics of stand-alone photovoltaic power system is studied to test its feasibility in remote and rural areas of Bangladesh and to compare renewable generators with non-renewable generators. The life cycle cost of these generators are determined using the method of net present value analysis. It is found that the life cycle cost of this experimental PV system is Tk. 43.40/kWh for one family (US $1.00 = Bangladeshi taka Tk.50.00). The life cycle cost for grid electricity is Tk. 20.00/kWh and Tk. 7.75/kWh for generation of fuel costs of Tk. 6.80/kWh and Tk. 0.47/kWh respectively. For a village 1 km away from the distribution line, this cost becomes Tk. 125.00/kWh for a family. For petrol generator life cycle cost is Tk. 50.00/kWh at fuel price of Tk. 22.00 per litre. For diesel generator life cycle cost is found to be Tk. 46.10/kWh at fuel cost of Tk. 15.00 per litre. It is observed that the life cycle cost of one unit of energy from grids that are 1 km away from a village is much higher than the cost of energy from a PV system. Thus, the use of PV system is economically feasible in rural villages and remote areas of Bangladesh, where grid electricity is not available.     

Size optimization of a PV/wind hybrid energy conversion system with battery storage using response surface methodology

This paper aims to show the use of the response surface methodology (RSM) in size optimization of an autonomous PV/wind integrated hybrid energy system with battery storage. RSM is a collection of statistical and mathematical methods which relies on optimization of response surface with design parameters. In this study, the response surface, output performance measure, is the hybrid system cost, and the design parameters are the PV size, wind turbine rotor swept area and the battery capacity. The case study is realized in ARENA 10.0, a commercial simulation software, for satisfaction of electricity consumption of the global system for mobile communications (GSM) base station at Izmir Institute of Technology Campus Area, Urla, Turkey. As a result, the optimum PV area, wind turbine rotor swept area, and battery capacity are obtained to be 3.95 m², 29.4 m², 31.92 kWh, respectively. These results led to $37,033.9 hybrid energy system cost, including auxiliary energy cost. The optimum result obtained by RSM is confirmed using loss of load probability (LLP) and autonomy analysis.     

Investment appraisal of a small, grid-connected photovoltaic plant under the Serbian feed-in tariff framework

Serbian government has recently introduced the system of feed-in tariffs for electricity generated from renewable sources. The proposed feed-in tariff for photovoltaic electricity is set to 0.23 €/kWh paid for 12 years, with the PV electricity produced after the first 12 years being sold at the grid electricity market price for the rest of the plant lifetime. Although such FIT could have been justified by the small, average retail grid electricity price of just 0.054 €/kWh for Serbian households, the investment appraisal of a real case of 2.82 kWp PV power plant in two Serbian cities of Zlatibor and Negotin, clearly illustrates that the proposed FIT framework is not sufficient to attract investments into PV in Serbia. In the second part of the paper, we have analyzed alternative, more reasonable feed-in tarrif frameworks, with the goal of selecting those able to sustain the PV adoption and diffusion in Serbia.     

Economic perspective of PV electricity in Oman

Solar and wind energies are likely to play an important role in the future energy generation in Oman. This paper utilizes average daily global solar radiation and sunshine duration data of 25 locations in Oman to study the economic prospects of solar energy. The study considers a solar PV power plant of 5-MW at each of the 25 locations. The global solar radiation varies between slightly greater than 4 kWh/m²/day at Sur to about 6 kWh/m²/day at Marmul while the average value in the 25 locations is more than 5 kWh/m²/day. The results show that the renewable energy produced each year from the PV power plant varies between 9000 MWh at Marmul and 6200 MWh at Sur while the mean value is 7700 MWh of all the 25 locations. The capacity factor of PV plant varies between 20% and 14% and the cost of electricity varies between 210 US$/MWh and 304 US$/MWh for the best location to the least attractive location, respectively. The study has also found that the PV energy at the best location is competitive with diesel generation without including the externality costs of diesel. Renewable energy support policies that can be implemented in Oman are also discussed.     

An experimental study on energy generation with a photovoltaic (PV)–solar thermal hybrid system

A hybrid system, composed of a photovoltaic (PV) module and a solar thermal collector is constructed and tested for energy collection at a geographic location of Cyprus. Normally, it is required to install a PV system occupying an area of about 10 m² in order to produce electrical energy; 7 kWh/day, required by a typical household. In this experimental study, we used only two PV modules of area approximately 0.6 m² (i.e., 1.3×0.47 m²) each. PV modules absorb a considerable amount of solar radiation that generate undesirable heat. This thermal energy, however, may be utilized in water pre-heating applications. The proposed hybrid system produces about 2.8 kWh thermal energy daily. Various attachments that are placed over the hybrid modules lead to a total of 11.5% loss in electrical energy generation. This loss, however, represents only 1% of the 7 kWh energy that is consumed by a typical household in northern Cyprus. The pay-back period for the modification is less than 2 years. The low investment cost and the relatively short pay-back period make this hybrid system economically attractive.     

Assessment of centralized grid connected wind power cost in coastal area of Pakistan

This work presents an assessment of per unit cost of electricity generated from 15 MW wind farm at 40 locations in the coastal areas of Pakistan using the method of net present value analysis. The Nordex N43/600 wind turbine has been selected and used as reference wind turbine. Wind duration curves were developed and utilized to calculate per unit cost of electricity generated from chosen wind turbine. In Sindh province, the minimum cost of electricity generated was found to be 4.2 ¢/kWh at Jamshoro, while the corresponding maximum was 7.4 ¢/kWh at Kadhan site. In Balochistan, the minimum cost of electricity generated was found to be 6.3 ¢/kWh at Aghore, while the corresponding maximum was 21.0 ¢/kWh at Mand site. The study concludes that at most of the locations especially in Sindh province, wind power is competitive to conventional grid connected thermal power even without considering the externalities.     

Performance of 170 grid connected PV plants in Northern Germany—Analysis of yields and optimization potentials

Within the German 1000 roof PV programme, about 2000 grid connected PV plants (1–5kW_p) with a total peak power of 5 MW_p were installed on the roofs of single and two family houses. In the Federal State of Lower Saxony, ISFH has been responsible for the technical inspections and the global monitoring of 172 PV plants up until now. The annual final yields range between 430 kWh/(kW_p^*a) and 875 kWh/(kW_p^*a) with a mean value of 680 kWh/kW_p^*a). Using the annual in-plane irradiation, we determine annual performance ratios in the range 47.5%–81% (mean 66.5%). A procedure to receive standardized performance ratios is introduced using actual peak powers of the PV modules and inverter-specific efficiencies. Typical curves of monthly values of the performance ratio are recorded. PV plants with low final yields are analyzed with respect to operational failures, partly shadowing effects, and poorness in maximum power point adaptation of some inverters. Optimization potentials are also discussed.     

An evaluation on the life cycle of photovoltaic energy system considering production energy of off-grade silicon

In this study, single-crystalline silicon (c-Si) photovoltaic (PV) cells and residential PV systems using off-grade silicon supplied from semiconductor industries were evaluated from a life cycle point of view. Energy payback time (EPT) of the residential PV system with the c-Si PV cells made of the off-grade silicon was estimated at 15.5 years and indirect CO₂ emission per unit electrical output was calculated at 91 g-C/kWh even in the worst case. These figures were more than those of the polycrystalline-Si and the amorphous-Si PV cells to be used in the near future, but the EPT was shorter than its lifetime and the indirect CO₂ emissions were less than the recent average CO₂ emissions per kWh from the utilities in Japan. The recycling of the c-Si PV cells should be discussed for the reason of the effective use of energy and silicon material.