Passive vapor generation systems with interfacial solar heat localization enable high-efficiency low-cost desalination. In particular, recent progress combining interfacial solar heating and vaporization enthalpy recycling through a capillary-fed multistage architecture, known as the thermally-localized multistage solar still (TMSS), significantly improves the performance of passive solar desalination. Yet, state-of-the-art experimental demonstrations of solar-to-vapor conversion efficiency are still limited since the dominant factors and the general design principle for TMSS were not well-understood. In this work, we show optimizing the overall heat and mass transport in a multistage configuration plays a key role for further improving the performance. This understanding also increases the flexibility of material choices for the TMSS design. Using a low-cost and free-of-salt accumulation TMSS architecture, we experimentally demonstrated a record-high solar-to-vapor conversion efficiency of 385% with a production rate of 5.78 L m−2 h−1 under one-sun illumination, where more than 75% of the total production was collected through condensation. This work not only significantly improves the performance of existing passive solar desalination technologies for portable and affordable drinking water, but also provides a comprehensive physical understanding and optimization principle for TMSS systems.

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Ultrahigh-efficiency desalination via a thermally-localized multistage solar still

A review on solar stills for brine desalination

Effect of using nanofluids and providing vacuum on the yield of corrugated wick solar still.

Thermal energy storage in district heating and cooling systems: A review

Theoretical and experimental parametric study of modified stepped solar still

An experimental study on a regenerative solar still with energy storage medium — Jute cloth

In this study, a detailed experiment has been conducted on a single-basin solar still which is modified with energy storage medium of black granite gravel. An attempt has been made to utilize the maximum amount of solar energy and to reduce the heat loss from the sides and bottom of the still. The conventional still is modified with an energy storage medium of black granite gravel of 6 mm size which is provided in the basin for different (quantity) depths. The black granite gravel functions as energy storage medium and also as an insulation layer to reduce the bottom and side loss coefficients. The black gravel is used for absorbing the excess heat energy from solar radiation during the noon hours. Due to this, the heat accumulated in the space between the water and glass surface is reduced and hence the temperature difference between the water and glass surfaces increases. The depth (quantity) of the gravel layer in the basin will influence the performance of the still and some of the parameters like basin temperature, water temperature, glass temperature and still productivity. This study deals with the effect of aforesaid parameters on the performance of the still. An attempt has been made to optimize the still performance for the above-mentioned parameters. A mathematical model is developed to estimate the water, gravel, and inside glass temperatures theoretically and to estimate the hourly and daily yield. To show the effectiveness of the modification, its performance is compared with the conventional still under the same climatic condition. It is found that the still yield is increased by 17-20% with almost no cost for this modification as black granite gravel is very cheap. Error analysis was done by comparing the theoretical and experimental results to show the validity of the mathematical model. It is found that the maximum percentage of discrepancy for all the parameters is about ±18%. Theoretical value of yield per day has 8% discrepancy over experimental value.

Effect of energy storage medium (black granite gravel) on the performance of a solar still

In the presented research paper, investigated the torsional performance of reinforced concrete beams with light emissions grade of cement utilizing Carbon fiber and its relative investigation with aramid fiber, for its torsional conduct, utilizing both exploratory and insightful strategies. A distinctive example of its strips folded over RC beams and the torsional conduct of these restrengthened beams is considered. Carbon fiber (CF) is utilized as outside support. Reinforced concrete beam retrofitted with CF tried for torsional disappointment utilizing lever arms exposed to torque. The beams have dimensions of 150mm in width and 200mm in depth and 1 m long, as planned according to IS456-2000. Three bars are intended for a twist. Steel has a stronger ultimate strength but a lower density than aramid FRP, as well as being easier to install and requiring no interim support until it reaches its full strength. The impact of various sorts and designs of CF on the initial stage of breaking load, extreme load conveying limit, and disappointment method of the beam are thought about and its relative examination utilizing finite element programming with aramid fiber gives a better outcome for additional investigation.

S. Shanmugasundaram

Papers

An experimental study on a regenerative solar still with energy storage medium — Jute cloth

Effect of energy storage medium (black granite gravel) on the performance of a solar still

Torsional performance of reinforced concrete beam with carbon fiber and aramid fiber laminates