The thermal analysis study done with the central receiver and MED plant outlines the importance that the TBT has on the sizing of a CSP+MED plant. The study suggests that increasing the TBT leads to much higher yields in water production while the electricity production is reduced by only a small amount. Still, it is difficult to compare units of water with units of electricity. Only when adding economic value to these products within the context of Namibia, a sensible comparison can be made in terms of revenue gained and whether such a project would make economic sense. SAM’s method of using a regression method to predict the PB performance is sufficient when CSP-only analyses are done. However, integrating a desalination plant into the PB as a condenser is a crucial component of this study and therefore it is suggested that a semi-detailed Rankine cycle be modelled for this study. Using the approach of Gauché et al. significantly reduces the computational time when calculating the hourly heliostat field efficiency. Large differences occur between this method and SAM at SM’s higher than 3. This is an issue that occurs because of attenuation losses that are not captured by Gauché et al.’s polynomial and should therefore only be used for high-level studies such as this one.
Parabolic dish collectors (PDC) as shown in Fig. 4 , concentrate the sunrays at a focal point supported above the middle of the dish. The complete system tracks the sun, with the dish and receiver progressing in tandem. This design removes the necessity for a HTF and for cooling water. PDCs offer the highest transformation efficiency of any CSP system. PDCs are expensive and have a low compatibility with respect of thermal storage and hybridization . Promoters claim that mass production will allow dishes to compete with larger solar thermal systems . Each parabolic dish has a low power capacity (typically tens of kW or lesser), and every dish generates electricity separately, which implies that hundreds or thousands of them are required to install a largescale plant like built with other CSP technologies . Maricopa Solar Project is the only operational PDC plant, with a net capacity of 1.5 MW. The power plant started functioning since January 2010 and is situated at Arizona, USA.
abundant but they do not provide on-demand, dispatchablity electric power like hydropower and geothermal generators. Integrating energy storage with solar and wind power improves overall system dispatchablity. The inclusion of back-up fossil fuel generation can further increase dispatchability, but this also decreases sustainability. Electricity access is low in sub-Saharan African relative to other locations in the world. Currently, only 20% of people in sub-Saharan Africa do not have access to electricity and that number is expected to reach only 40% by 2050. Even areas with an electrified grid are subject to power scarcity issues that decrease wellbeing and limit economic development. For example, industries and manufacturers in sub-Saharan Africa experience an average of 56 days of power outages per year, in comparison to 1 day in 10 years in the United States . The rate of economic growth per capita is expected to increase by an average of 2.2 percent per year if infrastructure and power reliability can be improved . This increase in reliability must also be met with decreases in power prices to further spur development. The average price of electricity in sub-Saharan Africa is an equivalent of 13 U.S. cents/kWh after applying subsidies to reduce the market cost from 19 U.S. cents/kWh . Another issue is the reliance on fossil fuels that exhibit price volatility and contribute to global warming and regional climate change. Large-scale renewable energy sources are an opportunity to address energy issues in sub-Saharan Africa by providing power that is more reliable, more affordable, and more sustainable.
Note that the collector field costs are based only on maintenance to the collector field, not to the power block or cooling tower, which would be appropriate if one were designing a plant to provide Industrial Process Heat (IPH) for a process such as desalination, rather than electricity. These results show that the maintenance costs for a small-scale IPH facility would be substantially less than for a small-scale CSP plant. This is partly due to the low efficiency of the ORC (7%) when producing electricity at this scale, and it is also partly due to the fact that for process heat, the maintenance costs for the power block and cooling tower do not apply. Even at a small scale, however, the annual cost of $7.81/kWt found in this study compares favorably to the current default value of $5/kWt provided in the System Advisor Model (SAM) for large-scale IPH plants , which is provided free of charge from the National Renewable Energy Laboratory (NREL).
Suid Afrika (SA) beoog om 42 persent elektrieiteit deur middel van herwinbare energie tegnologie te produseer teen 2030. Om hierdie doelwit te bereik het die regering ‘n program: “Renewable Energy Independent Power Producer Programme (REI4P)” van stapel gestuur om die integrasie van herwinbare energie met huidige bronne te vergemaklik. Die land het oorvloedige sonkrag en die potensiaal om dit te benut vir energie deur middel van konsentrasie van sonenergie “concentratingsolarpower” (CSP) is reeds bewys. In 2010 was CSP een van die hoof geprioritiseerde herwinbare tegnologieë in Suid Afrika en is 600 MW deur die REI4P aangekoop. Dit sluit sewe aanlegte wat gebou, of in aanbou is, in. Teenstrydig daarmee lyk die toekoms van CSP in Suid Afrika swak, aangesien die onlangese opdatering van die regering se “Integrated Resource Plan” (IRP) geen toekenning vir ‘n nuwe CSP aanleg na 2030 insluit nie. Verskeie faktore het aanleiding gegee tot hierdie gaping in aanvaarding van die CSP tegnologie. Baie min CSP aanlegte is gekoppel aan die nasionale rooster en daar is beperkte navorsing en inligting beskikbaar wat die effek en skaalvoordele bespreek. Die impak van hierdie tegnologie op Suid Afrika se handel en plaaslike vervaardigings industrie, asook die plaaslike navorsing, ontwikkeling en innovasie was tot op datum nie ondersoek nie.
Water scarcity is a threat for mankind and its symptoms have been aggra- vated by several factors such as climate change effects, increase in population and accelerated urbanization. Among the alternatives of water supply, the desalination has become one of the most sustainable solutions to provide freshwater. However, the process of desalination requires high quantities of energy and the use of renewable energy sources can make the technology af- fordable for regions characterized by freshwater scarcity where the supply from electricity is not accessible. In this context, wind power can be singled out because of the constant innovations and progress of the wind power in- dustry, which grows rapidly worldwide. This study aims to use patent appli- cations for the technological forecasting of wind-powered desalination in or- der to analyse its innovation potential. China is the leader country in the technological development of this field, accounting for almost 80% of patent applications in the last 17 years. The patents analysis showed that innovations are being developed to combine the wind power, mainly, with Reverse Osmo- sis technology. This study also shows the immense potential of integrating of these two technologies as a strategic alternative for remote regions affected by a lack of freshwater and with no electricity access.
Desalination was first used by Greek sailors in the 4th century BC to evaporate seawater and create drinking water. It is by definition a process removing minerals and salts from saline water to produce freshwater, that can be used for human use or irrigation. Desalination uses the principle of osmosis to remove salt and other impurities, by transferring water through a series of semi-permeable membranes. Thermal desalination uses heat, often waste heat from power plants or refineries, to evaporate and condense water to purify it. and in order to improve the efficiency of the plants.
Capacitive deionization (CDI) is a non-membrane process that uses electricity to remove ions from the water. An electric field will be provided that attract positive and negative electric chargers inside the solution by applying an electrical potential difference on the plate (electrode) of the CDI’s cell. The ions which are contained in salty water will separate and attract to the plate by passing the flow of water between the electrodes. In comparison with other desalination technologies, CDI process is popular method due to high energy efficiency operation. The reason of notable energy efficiency benefit is that in CDI the energy can be recovered. CDI by nature is a supercapacitor and can store energy. Therefore, energy can recover in this system. CDI operation consists of two stages. As the first stage starts, the DC voltage is applied to CDI electrode for removing the ions. This stage continues up to the ions saturation of the plates and is called purification stage. The second stage starts by shorting the electrodes or transferring the stored energy from the CDI. The feeding water flows between the electrodes to purify them. This stage is called purging stage. As Fig. 6 depicts, A CDI plant can consist of two CDI cell or one CDI cell and one supercapacitor (for saving the energy). A solar system which is comprised of photovoltaic cells generates electricity for supplying the plant. Maximum power point tracker (MPPT) block take maximum available power from the solar system. On the other hand, it improves the efficiency of power production [18, 19]. The output power of MPPT feeds storage system and main system that contains CDI cells. The storage system is considered for stable operation of the plant during all day long. The aforementioned systems are constituted energy supply section which is operated as an input energy feeder. By using this energy section, the initial energy of the main system is provided through the power electronic converter for feeding the CDI 1 in purification stage. At the end of the
The objective of this study is to check the possibility of producing potable water from seawater using low cost technique depends on concentrated solar rays by mirrors specially in autumn and winter g. pilots open site, ASU. The system used 3 concave mirrors and directed to let mirrors receives sunrays and concentrated it on the pilot for the whole sunny period. The measurements for quantities, temperature and TDS for the inlet and outlet made with the measuring of air temperature and sunshine period among the day. The tests covered three months between autumn and winter to be in the worst climate for the system operation that depends mainly on sun and temperature. The results were good for product quantity The study shows that the fresh water quantity is proportional with air temperature and its 40 ppm even how much the salinity of the influent seawater that ensure the
A water distiller captures the process of evaporation and condensation in a chamber, leaving behind all impurities, such as inorganic materials and chemicals. It can even purify seawater. Distillation is one of the mankind‘s earliest forms of water treatment, and it is still a popular treatment solution throughout the world today. In ancient times, the Greeks used this process in their ships to convert sea water to drinking water and also to treat water in other area that are fouled by natural and unnatural contaminants. Solar still having the advantage of low capacity and self-reliance is best suited as; they can produce pure water by using solar energy only, and do not need other expensive energy sources such as fuel or electricity. Among the various types of solar stills, the single passive solar distillation system is the most simple and least expensive. This system is complete and requires no additional infrastructure except the necessary raw water and sufficient sunlight.
Sadly, as it may be, some sort of a hidden agenda to elicit large profits may be in the works in the minds of many business executives looking to tap into this futuristically very profitable undertaking. Such mind-set is ac- ceptable and encouraged, and eventually mankind will benefit from such unsettling agenda. The analysis above demonstrates that seawater desalination is a viable business sector with a very profitable outlook. The utilization of direct solar energy is a definite plus technically and economically. The low cost of employing solar energy signifies its potential value. Although land cost has never been mentioned in the costing of this example, due to the government control over public land in Saudi Arabia, however, public land throughout the world can be leased at reasonable rates when utilized for public benefits. The low construction and maintenance cost of the solar energy for desalination of seawater outweighs legal, legislative or political obstacles. It is easy to build easy to maintain and unlike the other two options, is not subject to market or political fluctuation and wrangling, respectively.
In 2010 the government presented the equally ambitious Growth and Transformation Plan (GTP) 2011-2015 that aims at increasing drinking water coverage, based on the government's definition, from 68.5% to 98.5%. Water sanitation and hygiene are core part of Ethiopia government policies where more than 250,000 youngsters die every year due to lack of safe water supply. Availability of pure water in the country is about 35% which is the least in Africa. This show that lack of access to safe drinking water makes children especially vulnerable to water borne diseases such as diarrhea [World Bank, 2011]. The water crisis also force millions of people mainly rural women and young girls to spend much hours for collecting and carrying water which is somehow pure for drinking. The availability of cost effective approach to harness the solar energy in solving the problem associated with potable water cannot be overemphasized. This is a major challenge in the developing countries today. Many health disorders in rural communities in the developing countries have been traced to intake of contaminated water. As result of this a lot of children in the country exposed to vulnerable water born disease. In addition to this rural women and children walk long distance for fetching water which is not that much pure. This intern may restrict their opportunities for education. For this reason, purification of locally available water is extremely important. This results in a very challenging situation for individuals trying to prepare pure water in local conditionso as to keep themselves and their families safe from the myriad diseases and toxic chemicals present in untreated water. However, one of the abundant energy sources which the country endowed to make it use for purification water is solar energy. According to Ethiopia metrology agency the total solar energy per annual is 6.25kw/m 2 /year. Therefore, there is a solution to this problem. Thus using solarwater still allows to utilize this cheap source of energy.
ABSTRACT: This paper represents the basic working model of CSP (ConcentratingSolarPower Plant) plant. There are different types of CSP plant like PTC (Parabolic Trough Collector) type, LFR (Linear Fresnel Reflector) type, parabolic dish Stirling Engine type, Central receiver type, described with their configuration. After that grid integration of CSP plant simulation is carried out in MATLAB-SIMULINK software. The simulation Results shows that CSP plant grid integration is acceptable. There is a cost analysis of CSP plant and PV plant also described in this paper.
As Gujarat is the state with a coastline of 1600 Kilometers which is highest in India, sea water is readily available to majority of the state. The geography is also such that the year-round weather of the state is comparatively warm to most of the states of India.
only problem is the tracking of the sun. Shatat et al (2013) study shows more opportunities of desalination system on renewable energy. In late 1950’s Multi Stage Flashing (MSF) system is introduced which is most helpful for solving the desalination demand. Dessouky et al. (2004) analysis the multistage flashing desalination and made the design correlation for MSF on discharge coefficient, heat transfer coefficient etc in the terms of pressure, temperature and brine concentration. Mohammed and Weshahi (2014) proposed the integration of organic Rankine cycle to the MSF for the heat recovery system. A comparison of R134a and R245fa as working fluid in ORC is more suitable for the integration.
Nowadays, with oil dominate over 40% of all worldwide energy, with the current continuous usage of non-renewable such as fossil fuel combustion now and soon will cause of the negative effect in using which cause of global climate change. In addition of increasing of oil price have made many countries to find another alternative that more reliable, cheaper and abundant of energy with environmentally friendly and ecological hazards associated with its production. The energy with environmental friendly is hydro, wind, geothermal and solar, as for solar it can be separated into two types that is Photovoltaic (PV) and ConcentratingSolarPower (CSP) technology.
Some initial experiments were carried out to determine the important parameters in order to determine the potential of the proposed work. The Convex lens of the Magnifying Glass available easily in local markets of dia. 10cm(4 inch) was chosen. The focal length of this lens was found out to be 18.5cms and the maximum temperature attended at the focal point is found out to be 195 0 C by placing a thermocouple junction under direct solar radiations. The Solar Collector is a Rectangular box of size 14.5cms x 21cms x 70cms made of plywood of 8 mm thickness. Six circular holes of 10cms dia. are cut where convex lens were fixed at the top of the box. The lenses used were the simple Convex Lens from Magnifying glass which is available easily in local markets. The lenses are fixed in the holes of the receiver box by Plaster of Paris (POP) as it provides easily removal of the lens for further adjustments and also easily available in market. The Collector Receiver is made of a Copper tube 6,25mm (1/4 th inch) in dia. and 1 mm thickness. The length of the tube is 75cms and is fitted in the Panel Box at its focal length. The tubes were provided with Flow valve to precisely control the flow rate of water through the panel. The Solar rays incident on the six lens area are concentrated at the focal point where the receiver tube is placed. Six thermocouples (J-type) are attached near the focus point in order to determine the surface temperatures and study the variation of these temperatures along the length of tube. The simple manual tracking mechanism with nut bolt arrangement is designed and manufactured to continuously track the sun. The Sun is tracked from East to West with axis of the receiver tube axis along North-South directions and the collector is inclined as per designed inclination. The inclination of the collector can be adjusted such that the incident radiations are normal to the collector surface. Two Flow Control Valves were installed at the inlet and outlet of the panel to precisely control the flow rate of water in the panel.
The impacts of cost reductions on the levelized cost of electricity (LEC) from CSP plants were estimated using a spreadsheet pro forma financial model of the type used in competitive industry to support power project planning and financing. The main analysis engine is a standard income/cashflow statement that combines energy production, revenue, costs (investment, operation and maintenance, fuel, etc.) and financial inputs (depreciation, insurance, taxes, interest, tax credits, return on equity, etc.) to arrive at levelized costs of electricity on a lifetime $/MWh basis. All evaluations were done on a lifetime $/MWh evaluated cost basis, in constant 2005 dollars, assuming 30 years of service for the facility.
over the coldest fraction. In this “thermocline” approach , the two temperature levels are naturally separated by the diﬀerence in density. Its major advantage is to reduce the overall cost of the TES unit (by about 30%) by using a single tank. Nevertheless, heat transfer by diﬀusion at the interface between the two temperature levels reduces the thermal eﬃciency. During the charging period, the coldest salt fraction is pumped at the bottom of the tank to be heated by the solar ﬁeld through a heat exchanger and to go back to the top of the TES tank. During the discharge step, the hottest salt fraction is pumped at the top of the tank to feed the power block and the resulting coldest salt is fed back at the bottom of the tank. Therefore, during those two oper- ating steps, the thermal gradient zone of the salt in the tank moves up (under charge) and down (during the discharge). Eﬀorts are made to develop ﬂoating insulating mem- branes of intermediate density following the thermocline during the charge/discharge periods.