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In the oil and gas industry, managing large quantities of produced water on a daily basis as the production blocks mature over time can be challenging, alarming for an effective and equally efficient treatment system to be embarked. A great solution would be to transform the produced water into a solar pond. Salt-gradient solar ponds (SGSP) are capable of storing large amounts of heat that could be used for producing electricity. Studies relevant to sodium bicarbonate solar ponds and its corresponding low-grade energy harvest are still at a pioneering stage, particularly in Malaysia. Thus, this paper investigates possible techniques and approaches to optimize thermal efficiency of solar ponds, using simulated produced water with high sodium bicarbonate content for power generation. It was determined that the best time to acquire the highest lower convective zone (LCZ) temperature is between 12 to 3 pm, when sun peaks right above the head. Also, addition of 18.8 litres of hydrochloric acid (HCl) had significantly reduced the pH and turbidity level of the pond, removing algae while improving solution clarity and heat storage at LCZ. Utilization of neoprene rubber sheet and black soil as insulators had proven to optimize the solar pond thermal efficiency, yielding highest LCZ temperature of 52.3°C with a maximum temperature difference of 18°C. Besides, the application of thermoelectric generator (TEG) to convert heat energy into sensible power output was explored through simple laboratory-scaled design and set-up, where a total of eight TEG modules were required to produce 0.28W of electricity. [ABSTRACT FROM AUTHOR]

In this work, we investigate numerically the effects of Soret and Dufour coefficients on heat and mass transfer in a Salt Gradient Solar Pond (SGSP) using the meteorological data of Tangier (Morocco). This SGSP consists of a square cavity filled with a mixture of water and salt. Transfers equations are solved via the finite volume method and the Gauss method. The SIMPLE algorithm is used to link the velocity and pressure fields. The numerical code, we developed in FORTRAN 95, is first validated by applying it to experimental and numerical studies of the literature. Then, we analyze the effects of Soret and Dufour coefficients on heat and mass transfer inside the SGSP. The results show that, during time, heat and mass transfer are not influenced by Soret coefficient. Nevertheless, increasing Dufour coefficient enhance heat and mass transfer inside the SGSP and disrupts its working mechanism. [ABSTRACT FROM AUTHOR]

Renewable energy has become popular alternative to fossil fuels as it can avoid environmental pollution such as air pollution. With the increase of human population and the demand of the power, power generation from renewable energy are greatly welcomed to be used for the future generation. One of the renewable energies that can be harnessed to meet our energy needs is solar energy. Salinity gradient solar pond is a low-cost solar collector and it can be used for a long term of heat storage. The storage of heat is useful for the generation of power during cloudy day and at night, in addition being very useful compared to other solar system. In this research, the solar pond was filled with saline water with increasing of density from top to the bottom as solar radiation was being absorb at the bottom of the pond. This project mainly focused on the construction of the salinity gradient solar pond and the methods to maintain the condition of solar pond. The parameters, such as temperature, density and pH value of water in solar pond was obtained as part of the maintenance and stability of the pond. [ABSTRACT FROM AUTHOR]

This paper concerns the simulation study of a mathematical model of the solar pond performance for collecting and storing the incident solar energy on the Karbala city (32.616° N, 44.025°E) in a form of thermal energy in its lower layer. It was found that there are several parameters affecting the amount of stored energy. The most effective factor is the amount of incident global radiation on the pond’s location. Therefore, a program in the FORTRAN language was established in the first stage to calculate incident solar radiation and the second stage to solve the One-Dimensional Finite Difference Method for heat transfer equations by using the arrays dimension. Various data for incident global solar radiation were in high agreement with NASA’s published data for Karbala city. Additionally, the obtained data of temperatures inside the solar pond were very similar to the published physical and experimental data of solar ponds. [ABSTRACT FROM AUTHOR]

In this study, a thermoelectric generator heat exchanger system was designed and simulated for electricity generation from solar pond. A thermoelectric generator heat exchanger was studied by using Computational Fluid Dynamics to simulate flow and heat transfer. A thermoelectric generator heat exchanger designed for passive inpond flow used in solar pond for electrical power generation. A simple analysis simulation was developed to obtain the amount of electricity generated at different conditions for hot temperatures of a solar pond at different flow rates. Results indicated that the system is capable of producing electricity. This study and design provides an alternative way to generate electricity from solar pond in tropical countries like Malaysia for possible renewable energy applications. [ABSTRACT FROM AUTHOR]

A salinity gradient solar pond is a combined solar collector and thermal energy storage system, and heat has been successfully extracted from the lower convective zone (LCZ) in working ponds using pump in the past. This paper discusses possibility of heat extraction from solar ponds using a passive heat exchanger by eliminating the use of pump. Here, the development of thermosiphon heat exchanger is presented theoretically applying the related mathematical equations. The developed mathematical model is solved using a simple excel program. The result from this investigation shows good prospects for thermosiphon heat exchanger to be applied for heat extraction from large scale solar ponds passively. [ABSTRACT FROM AUTHOR]

As the penetration of PV on electrical grids worldwide is increased, we approach a point where solar resource variability becomes an issue that needs addressing. Solar resource variability occurs across a wide range of timescales: from intraday with the passage of clouds to seasonal with the rotation of the earth around the sun. We investigate in this paper the effects and solutions to 1-day or longer variability, variability linked to meteorological phenomena at the continental and seasonal spatiotemporal scales. Two supply-side approaches to solving the problem of stochastic and deterministic resource variability these timescales are investigated: bulk energy storage and long distance interconnection with the geographic dispersion of solar generating facilities. We have developed a quantitative analytical framework by which to weigh the environmental and economic tradeoffs between these two approaches for a given geographic region. We use 10 years of globally distributed, dailyaveraged, satellite-derived surface and top-of-atmosphere shortwave downward radiative flux data from the International Satellite Cloud Climatology Project (ISCCP) via NASA's Surface Meteorology and Solar Energy (SSE) database to model photovoltaic production across the globe. Herein, we discuss the model's operation, apply it to regions spanning the Western hemisphere and provide a discussion of the results. [ABSTRACT FROM AUTHOR]

A two-dimensional numerical model is developed in order to simulate the transient thermal behavior of a salt gradient solar pond. Transient dimensionless governing equations in the form of mass, momentum, energy and concentration are discretized by employing the finite volume method and solved by using SIMPLE algorithm. Ponds with different aspect ratios are considered. The pond walls shadows and radiation attenuation in water are among the parameters whose influences on the pond thermal and flow fields are determined and discussed. [ABSTRACT FROM AUTHOR]