DEVELOPMENT OF WATER CULTURE SYSTEM DEPENDING ON RENEWABLE ENERGY TO SUIT REMOTE AREAS

Abstract

Nowadays, seeing the increase of human population, an emphasis on higher vegetable production all year round is noted. To response to this demand,sustainable development aims towards upcoming the target of optimizing crop yield by intensifying agriculture (Maloupa, 2000). This intensification conjoined with the shortage of water resources and arable lands can be achieved onlythrough the adoption of promising agricultural practices such as soilless culture. Soilless culture covers all methods and systems of production tool using mineral solution for the plant nutrition with another substrate or support than soil (Resh, 1989; Robin, 1998; Butt et al., 2004; Sheikh, 2006; Gruda, 2009) such as water culture, gravel culture, aeroponics, tube culture and nutriculture(Schwarz, 1994). It can be done on open or closed system (Baas et al., 1995; Papadopoulos et al., 1999). The increase in crops production through nutrient culture systems is mainly an export oriented process for meeting the demand of the increasing Egyptian population and consequently, increasing the food consumption. The use of solar photovoltaic cells as the power source for pumping water is one of the most promising areas in solar photovoltaic applications. With the increasing use of water pumping systems, more attention has been paid to their design and optimum utilization in order to achieve the most reliable and economical operation. This study aims to evaluate two closed solar pumping systems with hydroponic (NFT) unit using (large and small scale-models with the same mechanism) to present a suitable solution for electricity problem in the remote areas, as well as aims to insert a better style of culture (hydroponic) which saves the water, to the area’s study, to solve the water rarity problem in arid areas. The experimental works were carried out at The New Valley, El-Dakhla, Mut city, and use the municipal water. In both; large scale-model and small –scale model a photovoltaic system is used at large scale system 4 modules of PV (connected in parallel) are used to provide the system with required electricity, each one is (75 watt, Monocrystallene, 12 volt and 4.8 A) with a charge controller (50A) , Battery (100 Ah) and Inverter (300 watt). The culture area was (3 m × 5 m), the testing period was from the first October until the last of December (2013), the upper tank was filled manually with water, and the nutrient solution is added with required rates, the water flows from the upper tank under the gravity via culture pipes (each one with four inches diameter and 3 m length) to the lower one (at ground level, then, the water was lifted to the upper tank by solar motor pump (AC motor pump,375 W, 220 V, 1500 rpm, 2.4 m3/h, 30 m head), and this recycle repeated many times, and the upper tank compensates the consumed water as a result of water plants consumption by refilling it manually. This system was pla