**5. Agrovoltaic concept for irrigation and potential in Pakistan**

Recently, scientists and renowned engineers introduced a unique concept named "Agrovoltaic" for addressing food insecurity and on-farm energy constraint in tandem. The concept is to harness solar energy by putting photovoltaic (PV) modules into the same agricultural area that is already being cultivated to produce agrarian commodities. The approach promotes sustainable rural development, and the preservation of biodiversity and the ecosystem by forming synergies between renewable energy and agriculture. In addition, the PV modules shielded the crops from harsh weather conditions. The concept might be expanded to develop an intelligent

vision-based irrigation system. **Figure 8** shows the generalized conception of AVIS. The AVIS concept mutually resolves the water and energy problems specifically for the countries that have groundwater reserves and solar energy harvesting potentials. The AVIS integrated Internet of Things (IoT) with the solar-driven irrigation system. The IoT comprising of soil sensors, weather sensors, crop sensors, and microcontrollers. The solar-driven irrigation system contains PV modules, AC or DC batteries, motors and pumps, sun trackers, etc.

The microcontroller is the computational hub of the AVIS which computes, planed, and regulates the components of the solar-driven irrigation system. The microcontroller collects data from the different sensors and executes the data processing activities. For instance, the soil sensor captures agricultural field information such as soil type, water holding capacity, and, most significantly, detects available moisture in the ground. The collected data aid in determining of irrigation volume needed in the field. Similarly, meteorological sensors included within the AVIS capture weather data such as solar radiation, daylight hours, ambient temperature, rainfall, etc. The obtained data will be used to evaluate the solar energy generation capacity and to cut off the irrigation system if the rain will forecast. The cropping data was utilized to calculate water demand based on crop water requirements and crop coefficients. The water data contains surface water availability as well as an estimate of the water shortage that can be met by pumping groundwater. Once the prerequisites were computed, the microcontroller equipped with AVIS actuated the solar pump to extract groundwater for a predetermined period of time.

**Figure 8.** *Agrovoltaic irrigation system (AVIS) conception.*

#### *Agrovoltaic and Smart Irrigation: Pakistan Perspective DOI: http://dx.doi.org/10.5772/intechopen.106973*

The working principle of the AVIS is based on the PV modules, which convert solar energy into electrical energy. The PV panels are interlinked with the solar motors either AC or DC motors to produce mechanical energy, which is then turned to hydraulic energy by the surface pumps or submersible pumps. The energy supply to the solar pumps will automatically be disconnected once the field requirements are accomplished. During off sunshine hours, AC or DC batteries are integrated into AVIS as a backup energy supply. The ability of a solar pumping system to pump water is determined by three major variables: pressure, flow, and pump power. For design reasons, pressure may be defined as the effort done by a pump to raise a specific amount of water to a storage tank, which is estimated by the elevation head (difference between water source and storage tank). The water pump will need a specific amount of electricity, which must be supplied by a PV array. The irrigation efficiency may be adjusted by using a high-efficiency irrigation system (HEIS) that is powered by PV modules. The benefits of the AVIS are as follows:


Pakistan is geographically positioned in the domain of the sunny belt of the world having long sunshine hours and receiving high solar irradiation, which makes it an ideal locality for solar energy-driven technologies. The daily mean global radiation on the horizontal surface in Pakistan ranges between 1900 and 2200 kWh/m2 , which can potentially generate 1.9−2.3 MWh of energy [53, 54]. The sunshine hours vary between 2000 and 3000 h per year, which reflects massive solar energy harvesting potential. The average solar radiation intensity ranges between 36.05 and 287.36 W/m2 in the country. Solar radiation intensities of more than 200 W/m2 were recorded in Sindh from February to October; in practically all parts of Balochistan from March to October; in NWFP, Northern Areas, and Kashmir from April to September; and in Punjab from March to October [55]. During the course of the year, the average solar radiation intensity in Pakistan, namely in the southern parts of Punjab; Sindh; and Balochistan, ranges from 1500 to 2750 W/m2 day−1 for a period of 10 hours every day. In the locations listed

#### **Figure 9.**

above, it is possible to generate between 45 and 83 megawatts (MW) of power every month through an area of 100 m2 [55, 56]. **Figure 9** presents a solar resource map of PV power potential, which indicates generating electric power between 3.4 and 5.6 kWh day−1. In this spectrum, the abundant supply of solar energy is promising to supply primary energy to AVIS.
