Later, in order to overcome the above problem, many active solar stills have been developed. Solar stills solar still is possibly the oldest method of desalination of water. Attempts have been made to increase the efficiency and productivity by preheating the saline water in solar stills. Attempts have been made to increase the efficiency and productivity by preheating the saline water of solar still. Monthly and annual performances of passive and active solar stills were studied for five weather stations.
Summer winter software that can improve the design and integration of passive solar principles. Multistage, multieffect active solar still is observed to give an average distillate output of 20 kgm 2 d. In fact, ancient civilizations used passive solar design. Why cant solar stills convert sea water into fresh water.
Its principle of operation is the greenhouse effect. But these sources do not always prove to be useful due to the presence of excessive salinity in the water. For singlebasin singleslope active solar still, stepped. Active solar stills use thermal collectors, photovoltaic panels, and. Pdf theoretical analysis of solar distillation using active solar still. The performance of active single slope solar still using different operational parameters is studied theoretically and compared with the experimental data for validation purposes, to find out best.
In addition to the active solar energy system, passive solar heating system can be used. Solar hot water systems use pumps or fans to circulate fluid often a mixture of water and glycol to prevent freezing during winter periods or air, through solar collectors, and are therefore classified under active solar technology some of the basic benefits of active systems is that controls usually electrical can be used to maximize their effectiveness. Different versions of a solar still can be used to desalinate seawater, in desert survival kits and for home water purification. Active solar stills can provide enhanced distillate productivity, as saline water is circulated and put in contact with an additional heat source which supplies extra heat to the system.
Can a solar still generate enough fresh water for survival. The main drawback of passive solar still is its lower efficiency and. Economic analysis also shows that active solar still is a good replacement of nonrenewable energy based water purification techniques. Saeedi and others published optimization of a pvt photovoltaicthermal active solar still find, read and cite all the research you need on researchgate. Windows act as collectors in a passive solar design, while active solar systems use additional equipment. The passive solar stills are conventional solar stills css which use the solar energy falling on the basin effective area as the only source of thermal energy. Solar stills can be classified into active and passive solar stills. From the study, they observed that, the double slope active solar still under natural circulation modes gives 51% higher yield in comparison to the double slope passive solar still.
The solar still process uses the sun instead of other sources such as fossil fuels to gain the energy needed for purification. Typical efficiencies for single basin solar stills. Solar stills for desalination of water in rural households. To produce significant amounts of water from a solar still would require either an extremely large region of ocean be covered with a condensing medium such as a plastic sheet. This is the main drawback of a passive solar still. Optimization of a pv t photovoltaicthermal active solar. This is a solar alembic, or pot still, made from square foot mirrors, which can produce between 2 and 5 ounces of distillate on a lazy sunny afternoon. Solar distillation systems can be classified as passive and active.
Monthly performance of passive and active solar stills for. A stepbystep guide on how to make a solar still with simple materials if stranded in an area with no water. Pdf the performance of active single slope solar still using different operational parameters is studied theoretically and compared with the. This paper presents the parametric study of passive and active solar stills integrated with a flat plate collector based on the computer based thermal models. Solar stills are then able to supply pure water for drinking and cooking, even in areas where. What is new are building materials, methods, and solar positioning considerations the south side of the home must be oriented to within 30 degrees of due south. Design of solar thermal systems calculation methods. Solar stills can be used in povertystricken areas, in deserts, at sea, and to help reduce energy costs and pollution as stills are environmentally friendly. Experimental study on performance of passive and active solar stills. Solar still,a water purifying technique project report 1.
It considers advanced modifications in the design and development of materials, single and multieffect solar stills with augmentation of different materials, energyabsorbing insulators, and mechanisms of heat and mass transfer to improve the loss of heat and enhance the productivity. There is a modern desalination plant in tugun at the gold coast. Solar distillation uses simple device called solar distillates in a process similar to the natural evaporation of water by sun heat. In this paper, the fabrication of seven solar still designs such as spherical solar still, pyramid solar still, hemispherical solar still, double basin glass solar still, concentrator coupled single. Pdf we have superfluous amount of solar radiation available on the earth which we can use for various purposes like conventional and non. In this article, different water desalination techniques with their economic analysis are briefly.
There is not enough sun at the location, or the buildings facade is too heavily shaded by adjacent structures or tr ees, but the roof is well exposed. Humankind has depended for ages on underground water reservoirs for its fresh water needs. Stranded on an island with just duct tape and plastic wrap, jamie constructs a solar still to create drinkable water from condensation. In this work, a single slope solar still having a transparent glass cover is considered to be heated at its bottom by a circulating heat transfer fluid. The science, purpose, and benefits of a solar still. Solar water distillation safe drinking water foundation. The thermal efficiency of double slope active solar still is lower than the thermal efficiency of double slope passive solar still. Chapter 17 solar energy pennsylvania state university. An active solar energy system is a solar water or spaceheating system that uses pumps or fans to circulate the fluid from the solar collectors to a storage tank subsystem. Exergy analysis of double slope active solar still under forced. The daily thermal efficiency of solar still varies from. Active solar systems engs 44 sustainable design benoit cushmanroisin 7 may 2019 there are situations where one may wish to go beyond passive solar gain.
Optimization of a pvt photovoltaicthermal active solar. Two basic types of solar stills are box and pit stills. For solar still activity with standards, teachers guide, and student instructions, please see the solar stills challenge pdf, part of the 2011 international year of chemistry, or pbs learning medias solar still activity for grades 312. Solar still,a water purifying technique project report. A solar still is a green energy product that uses the natural energy of the sun to purify water. There are different types of survival solar stills or vapor stills. Solar still efficiency n is the amount of energy utilized in vaporizing water in the still over the amount of incident solar energy on the still q t in jm2 day. Solar stills aston publications explorer aston university. The difference between active and passive solar systems. A schematic diagram of typical basin type solar still is shown in figure 1. One of the main benefits of using them is that they can be used to increase the effectiveness of your solar system. If the solar system cannot provide adequate space heating, an auxiliary or backup system provides the additional heat. How to make a solar still dont buy plastic jugs of distilled water when you can convert it from undrinkable water with this diy project. A project report on solar still submitted in partial fulfillment for the award of the degree of bachelor of technology in mechanical engineering from rajasthan technical university, kota session 2012 guided by.
While passive solar heating employs methods to capture heat from the sun, it does nothing to actively enhance the process. It is also helpful to understand specific savings in cost for buildings that. This is shown in illustration 171, based on the information given in table 171. Optimizing an active solar still for sea water desalination. There are two basic types of active solar heating systems based on the type of fluid either liquid or air that is heated in the solar energy collectors.
Productivity enhancement of solar still with pv powered heating. Schematic view of an active solar still coupled with a fiatplate collector. Guide to passive solar home design by using the basic physical. Saeedi and others published optimization of a pv t photovoltaicthermal active solar still find, read and cite all the research you need on researchgate. Purifying water using passive solar water distillation. A solar still distills water with substances dissolved in it by using the heat of the sun to evaporate water so that it may be cooled and collected, thereby purifying it. Fath elbanna for desalination and energy technology, alexandria, egypt keywords. Performance improvement of a passive solar still in a.
In case of active solar still, an additional source of thermal energy is required for faster evaporation inside the same passive solar still. Parametric study of an active and passive solar distillation system. Economic feasibility evaluation of solar distillation. Active solar panels rely on external energy sources only. Passive solar water distillation is an inexpensive, lowtech alternative for pure drinking water without bottles, including types of distillers, cost comparisons, going automatic or electric.
Active still, basin still, collector, concentrator, forced circulation, greenhouse, passive still, wick still contents 1. Active solar systems use hot water pumps or fans to pump fluids. This experimental study has been carried out to measure the effect of ethp solar collector by natural convection on solar still. Weve listed some of the features of the active solar systems for you to have a. Active solar heating systems use solar energy to heat a fluid either liquid or air and then transfer the solar heat directly to the interior space or to a storage system for later use. Monthly performance of passive and active solar stills. In conventional passive solar stills, the solar radiation passes. Pdf performance study for active solar stills based on energy. Pdf on feb 17, 2016, sorabh rai and others published active solar still find, read and cite all the research you need on researchgate. Pdf theoretical analysis of solar distillation using. Heat distribution passive solar design allows solar heat to circulate from collection and storage points to different areas of the house.
Ive posted here about the square foot solar cooker, and here is another of the many uses for it. Solar stills are being used in countries where potable water is not readily available. From this study it has been observed that the productivity of solar still has been increased with decreasing in water. A strictly passive design will rely on natural heat transfer, but some applications use fans, ducts, and blowers to help distribute heat. However, in the active solar still, extra thermal energy is given to the passive solar still for faster evaporation, and hence increasing productivity. Sea water desalination through solar radiation distillation process can achieve low cost and sustainable fresh water for remote dry areas. History of passive solar energy university of north. Chennai, jodhpur, kolkata, mumbai and new delhi in india. Guide to passive solar home design department of energy. In a solar still, impure water is contained outside the collector, where it is evaporated by sunlight shining through clear plastic. Solar radiation is the input energy of the passive solar stills, but the efficiency of the system is low. They are used in areas where drinking water is unavailable, so that clean water is obtained from dirty water or from plants by exposing them to sunlight.
A thermal model for predicting the performance of a solar still with. They all basically use the same principle, but have different shapes and ways of catching the liquid. Pdf performance analysis of active solar still with ethp. While many people are aware of active solar energy systems, such as solar panels, passive solar energy is a division of solar energy that uses the suns energy in a more natural manner.