Solar Water pumping

Irrigation represents the largest share of energy consumption in agricultural holdings devoted entirely to crop production. Pumping systems are, in almost all farms, driven by electric motors or combustion engines (gas oil). This significantly increases the operating costs. The irrigated sector is also the largest consumer of water resources in Tunisia. It uses about 82% of the country's water potential. This includes large irrigation schemes from large dams, small perimeters from well and boreholes, and floodwatering. The average demand for water per hectare, actually irrigated, is estimated at 5 500 m3, with, however, large disparities depending on the type of crop in the region.

Traditional irrigation has several disadvantages among which:

Low storage rate in the soil Therefore, the optimization of the irrigation system would allow a large reduction in the volumes pumped, which leads to a reduction in both the energy bill and the invoice for irrigation water. Localized irrigation (drip irrigation) is in most cases the most economical and reliable method of irrigation. It saves water, and therefore energy, about 70% compared to gravity irrigation and 30% compared to sprinkler irrigation.

PHOTOVOLTAIC PUMPING AND KEY COMPONENTS

Photovoltaic pumping (PV) allows the irrigation of farms in isolated sites as well as those connected to the network. To use solar energy, the irrigation device is supplemented by photovoltaic panels.
There are two great options for PV pumping:

• with batteries, to store the generated electrical energy, which allows to have a water availability outside the hours of sunshine
• without batteries, the availability of water during the night or during low sunlight days is provided by a water storage tank.