Uzair Sajjad

By Muhammad Sultan, Muhammad Bilal, Takahiko Miyazaki, Uzair Sajjad and Fiaz Ahmad

Nowadays, atmospheric water harvesting (AWH) became very essential to provide fresh potable water. This technique is in practice since 1900 (US661944A) by Edger S. Belden. Atmospheric water is a source of freshwater with 13000 trillion liters availability of water at any time and can be utilized in overcoming water shortage, especially in arid and rural areas. It holds up the water molecules in the form of vapors and accounts for adding 10% of all freshwater present on the earth. Mainly, the two most common methods have been used for the extraction of atmospheric water. First, the ambient air is cooled below the dew point temperature, and second in which the moisture in atmospheric air is adsorbed/absorbed using desiccant materials. Conventional vapor compression, thermoelectric cooling, dew, and fog water harvesting based systems/technologies possess some limits in terms of energy requirements, less efficiency, and high cost. However, the adsorption based AWH technology is relatively cheaper, environment friendly, and can be operated by a low-grade thermal energy source. The limited availability of commercial instruments to harvest atmospheric water using adsorbents indicates a lack of fundamental studies. The fundamental research on water adsorption, adsorption kinetics, regeneration conditions, and water collecting surface designs has not gained as much interest as required in the field of atmospheric water harvesting. In this regard, this book chapter discusses and presents the progress in the field of adsorbent materials and system designs along with the future directions to accelerate the commercialization of this technology.

Part of the book: Technology in Agriculture

By Hafiz M. Asfahan, Muhammad Sultan, Fiaz Ahmad, Faizan Majeed, Md Shamim Ahamed, Marjan Aziz, Redmond R. Shamshiri, Uzair Sajjad, Muhammad Usman Khan and Muhammad Farooq

The present study aims to investigate the prospects and challenges that need to be encountered for the adaptation of the novel agrovoltaic irrigation system (AVIS) in Pakistan. The agro-production scenario in Pakistan is periodically declining and leading toward the high delta crops, which develop severe pressure on the conventional energy and water resources. Groundwater might be a viable water source, but its pumping requires massive energy. In addition, excessive pumping declines the water table at a higher pace as compared to the recharge rate hence leading the country toward the exploitation of the valuable reservoir. The AVIS could be an energy-efficient and reliable irrigation solution in a manner of harvesting solar energy for driving smart irrigation systems capable to pumps the metered groundwater according to field requirements. Lack of local understanding, skilled/technical personnel, dependence on local technology, and major capital expenditures might impede technological adaption. The government should take necessary measures to replenish the groundwater reservoirs and also execute research projects that strengthen ground knowledge of AVIS.

Part of the book: Irrigation and Drainage

By Nadia Riaz, Muhammad Sultan, Hadeed Ashraf, Muhammad Hamid Mahmood, Fiaz Ahmad, Muhammad Usman Khan, Muhammad Farooq, Uzair Sajjad, Muhammad Wakil Shahzad and Zhaoli Zhang

Evaporative cooling systems have evolved as highly effective greenhouse-control solutions, particularly in hot and dry places such as Multan, Pakistan. This chapter evaluates the performance of direct (DEC) and indirect evaporative cooling systems (IEC) for an asymmetric greenhouse using TRNSYS software. The performance of the systems was assessed in terms of simulated ideal vapor pressure deficit (VPD), temperature, and humidity for tomato cultivation. According to the results, the DEC system effectively reduced the temperature, while the IEC system effectively managed the humidity. The DEC system showed maximum energy saving of up to 40% in hot and dry months. The combination of both DEC and IEC systems produced the optimum level of temperature and humidity for increased tomato output, energy savings, and water usage efficiency. A higher (up to 0.35 kg/h) evapotranspiration mass flow rate was observed in the middle of the year in the case of the second and fourth system configurations. Findings from this study highlight the need for sustainable, energy-efficient cooling methods for greenhouse agriculture.

Part of the book: Air Conditioning Technologies and Applications

By Muhammad Ali Imran, Muhammad Sultan, Muhammad Wakil Shahzad, Muhammad Ahmad Jamil, Hafiz M.U. Raza, Muhammad Hamid Mahmood, Muhammad Asad Ali, Muhammad Haseeb Siddiqui, Uzair Sajjad and Zhaoli Zhang

This study explores the applications of hybrid indirect evaporative cooling (IEC) systems as an energy-efficient and climate-resilient alternative approach to conventional systems and their viability under different climates, offering cooling solutions. This book chapter systematically reviews standalone and hybrid IEC systems that incorporate mechanical vapor compression (MVC), desiccant dehumidification, and other innovations to overcome the limitations of conventional EC systems, particularly in humid and hot varying conditions. In this regard, a wide spectrum of state-of-the-art applications is assessed, including human thermal comfort in various types of buildings, crops in greenhouses, comfort of livestock in shelter houses, fresh and dried food storage, and industrial processes, for example, artifact preservation, tobacco curing, rubber goods, and mobile systems. Explored case studies and their prospective performance display that hybrid IEC systems have great potential to enhance energy efficiency, performance, and environmental sustainability. This assessment offers critical insights for professionals and policymakers toward the expansion and implementation of hybrid IEC systems in numerous areas.

Part of the book: Energy Engineering