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The power output of Photo-voltaic modules is generally rated at STC (Standard Test Condition), 1000W/m² irradiance, 25°C temperature and 1.5G Air Mass. But in actual field condition the situation is different from STC. Output of PV module is a function of Irradiance, ambient temperature, wind speed and module temperature. It is well established that power output of PV module decreases with increase of module temperature. So it is important to know the temperature of PV module to determine the reduction in power output due to temperature. Module temperature can be determined if irradiance at that instant and NOCT value of that module is known. This work presents the variation in NOCT value with respect to rated power output of PV module and comparison of NOCT values for same rated power mono and multi crystalline Si modules from various manufacturers. According to this study NOCT value increases with the wattage of PV module. For same rated power modules, NOCT value of mono crystalline Si is more than multi crystalline Si.

This study aim to use the finite volume method to solve differential equations related to three-dimensional simulation of a solar collector. Modeling is done using ANSYS-fluent software program. The investigation is done for a photovoltaic (PV) solar cell, with the dimension of 394 × 84 mm², which is the aluminum type and receives the constant heat flux of 800 W.m⁻². Water is also used as the working fluid, and the Reynolds number is 500.

In the present study, the effect of fluid flow path on the thermal, electrical and fluid flow characteristics of a PV thermal (PVT) collector is investigated. Three alternatives for flow paths, namely, direct, curved and spiral for coolant flow, are considered, and a numerical model to simulate the system performance is developed.

The results show that the highest efficiency is achieved by the solar cell with a curved fluid flow path. Additionally, it is found that the curved path’s efficiency is 0.8% and 0.5% higher than that of direct and spiral paths, respectively. Moreover, the highest pressure drop occurs in the curved microchannel route, with around 260 kPa, which is 2% and 5% more than the pressure drop of spiral and direct.

To the best of the authors’ knowledge, there has been no study that investigates numerically heat transfer, fluid flow and electrical performance of a PV solar thermal cell, simultaneously. Moreover, the effect of the microchannel routes which are considered for water flow has not been considered by researchers so far. Taking all the mentioned points into account, in this study, numerical analysis on the effect of different microchannel paths on the performance of a PVT solar collector is carried. The investigation is conducted for the Reynolds number of 500.

The purpose of this paper is to investigate the effects of concavity level on performance parameters of a parabolic fin under the influences of natural convection and radiation.

Computational fluid dynamics software (FLUENT) is used for the heat transfer analysis. Optimum fin geometry is searched in order to maximize the heat dissipation from fin to the ambient while minimizing the volume of fin.

The fin profile with concavity level of 2 dissipates 14.92, 17.53, 24.33 and 26.60 percent more heat and uses 34.62, 49.64, 57.66 and 63.09 percent much material compared to the fin with concavity level of 4, 6, 8 and 10, respectively. It is also observed that the amount of heat dissipation per mass considerably increases with increasing concaveness.

The research was carried out for five different concavity levels in the range of 2-10.

The results can be used in passive cooling applications of PV systems. Also, heat sinks for CPU cooling can be redesigned with respect to the results obtained from the research.

In this paper, effects of concavity level on performance parameters of a parabolic fin are investigated for the first time. It is observed from the numerical results that the fin profile with higher concavity levels provides a cheaper and lighter heat dissipation device so it is recommended for the applications where the weight and the cost are primary considerations such as cooling of photovoltaics.

This study aims to analyze the effects of variations in annual real interest rates in the assessment of the techno-economic feasibility of a hybrid renewable energy system (HRES) for an off-grid community.

Hybrid Optimization of Multiple Energy Resources (HOMER) software is used to propose an HRES for Abadam community in northern Nigeria. The HRES was designed to meet the basic needs of the community over a 25-year project lifespan. Based on the available energy resources in the community, photovoltaic (PV), wind turbine, diesel generator and battery were suggested for integration to serve the load requirements.

When the annual real interest rates were taken as 10 and 8 per cent, the total amount of total energy fraction from PV, wind turbine and the diesel generator is 28, 57 and 15 per cent, respectively. At these interest rates, wind turbines contributed more energy across all months than other energy resources. The energy resource distribution for 0, 2,4 and 6 per cent annual real interest rates have a similar pattern, but PV contributed a majority of the energy.

This study has used annual real interest and inflation rates dynamic behavior to determine optimal HRES for remote communities. Hence, its analysis will equip decision-makers with the necessary information for accurate planning.

The results of this study can be used to plan and design HRES infrastructure for off-grid communities around the world.

Any major dictionary needs to be continuously updated to keep current with the rapid growth of language. Faced with the need for such endless supplementation, Oxford University Press, in considering the available choices, concluded that automating the Oxford English Dictionary offered the only practicable solution. Traditional “cut‐and‐paste” methods of revision were ruled out as inadequate to meet the requirements of a task of such staggering proportions. But even if Oxford University Press had not planned to revise or enhance the Oxford English Dictionary, automation would still have brought enormous benefits to those who make extraordinary demands on dictionaries, for a traditional printed dictionary is a very unsatisfying reference tool in many ways, serving only if its conditions of strict lineality are accepted. If, on the other hand, an unreasonable demand of a dictionary is made, such as “Print out two carefully dated lists of all English adjectives ending in ‐ic and ‐ical,” then the traditional dictionary is about as useful as a sling‐shot or a royal command that the tides cease. Computerization, thus, can transform the linear reference tool into a versatile research tool with multiple points of access and provide scholars with a lexicographical research tool of unparalleled subtlety and power.

The purpose of this paper is to design and implement a directly cooled photovoltaic thermal (PV/T) hybrid system.

The research design subjects, instruments and methods that were used to collect data are as detailed in the paper. Two polycrystalline photovoltaic (PV) modules were used in this study.

The directly water-cooled PV module (PV/T) was found to operate better as compared to a naturally cooled module for the first three months. The PV/T initially operated at a higher electrical efficiency for 87 per cent of the day. The monthly energy-saving efficiency of the PV/T was found to be approximately 61 per cent, while the solar utilisation of the naturally cooled PV module M1 was found to be 8.79 per cent and that of M2 was 47.93 per cent.

The major limitation was the continued drop in efficiency after the first three months of the PV/T placed outdoors. The fall in the efficiency was attributed to water ingress.

Direct water cooling of PV modules is possible, only that a better sealing is needed to prevent water ingress.

PV air cooling has been researched on. Use of water as a cooling medium has been carried out using serpentine pipes or riser tube, and no direct water cooling on the back of the module has been researched on.

The malfunction variables of power stations are related to the areas of weather, physical structure, control and load behaviour. To predict temporal power failure is difficult due to their unpredictable characteristics. As high accuracy is normally required, the estimation of failures of short-term temporal prediction is highly difficult. This study presents a method for converting stochastic behaviour into a stable pattern, which can subsequently be used in a short-term estimator. For this conversion, K-means clustering is employed, followed by Long-Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) algorithms are used to perform the Short-term estimation. The environment, the operation and the generated signal factors are all simulated using mathematical models. Weather parameters and load samples have been collected as part of a data set. Monte-Carlo simulation using MATLAB programming has been used to conduct experimental estimation of failures. The estimated failures of the experiment are then compared with the actual system temporal failures and found to be in good match. Therefore, for any future power grid, there is a testbed ready to estimate the future failures.

The case, briefly reported in the last issue of BFJ, an appeal to a Milk and Dairies Tribunal arising out of a local authority's refusal to grant a licence to a milk distributor because he failed to comply with a requirement that he should provide protective curtains to his milk floats, was a rare and in many ways, an interesting event. The Tribunal in this case was set up under reg. 16(2) (f), Milk (Special Designation) Regulations, 1963, constituted in accordance with Part I, clause 2 (2), Schedule 4 of the Regulations. Part II outlines procedure for such tribunals. The Tribunal is similar to that authorized by S.30, Food and Drugs Act, 1955, which deals with the registration of dairymen, dairy farms and farmers, and the Milk and Dairies (General) Regulations, 1959. Part II, Schedule 2 of the Act provided for reference to a tribunal of appeals against refusal or cancellation of registration by the Ministry, but of producers only. A local authority's power to refuse to register or cancellation contained in Part I, Schedule 2 provided for no such reference and related to instances where “public health is or is likely to be endangered by any act or default” of such a person, who was given the right of appeal against refusal to register, etc., to a magistrates' court. No such limitation exists in respect of the revoking, suspending, refusal to renew a licence under the Milk (Special Designation) Regulations, 1963; an appeal against same lies to the Minister, who must refer the matter to a tribunal, if the person so requests. This occurred in the case under discussion.

Without aspiring to emulate Robert Browning's song thrush, we venture to repeat an admonition on smoking in the food trade of almost a decade ago. (The Smoking Habit, 1962, BFJ, 64, 79). The first time it coincided with a little research we had undertaken, which later saw the light of day epitomized in article form and was enthusiastically (sic) commented upon in sections of the press and then died as if it had never been born. (Tobacco and Lung Cancer, 1965, Med. Offr., 2955, 148). Now, it coincides with the most concentrated, officially inspired, campaign, so far, mounted against the evils of smoking. The most striking fact about all these national efforts every few years is the lack of success in real terms. A marketing organization achieving such poor results would count it a costly failure. It would be unfair to say that none have given up, but with a habit so ingrained, determination is required and in many, if not most, of those able to refrain, the craving is so great that they are smoking again within a week or so. Overall, the smoking population is enormous, including, as it does, girls and women‐folk. Once, it was undignified for a woman to be seen smoking. We recall a visit by Queen Mary to the village Manor House, just after the First War; she was an expert in antique furniture and came to see the manor's collection. When Her Majesty asked for a cigarette, the village rang with astonishment for days. Nothing as amazing had happened since Cavaliers and Roundheads tethered their horses beneath the three great poplars which stood on the green. “Queen Mary! 'er smokes!”