Solar energy has emerged as an inexhaustible force needed by poor farmers to irrigate their fields, but a lack of control and abusive practices can lead to a new «hidden drought» in aquifers.
Solar technology in agriculture, which is in full expansion, allows increasing water extraction for the surface irrigated, and as a result promotes crop productivity. An equation that is not entirely positive unless the environmental sustainability factor is ignored, given the inherent risks it entails for aquifers, stated Karen Villholth, an expert from the International Institute for Water Management (IWMI).
«In many countries these systems have gone badly because they aren’t being developed in a sustainable manner,» said Villholth, adding that it was very difficult to recover water resource once they were used. That is why she says that an ounce of prevention is better than a pound of cure and recommends adapting irrigation plans to each place’s circumstances, limiting the use of groundwater, allowing it for only certain crops, supervising the operation and promoting the water recharge of aquifers.
According to estimates released this week in an international forum in Rome, 41% of the irrigated areas are irrigated with groundwater and up to 27% of these waters are pumped in an unsustainable manner.
The risk of an underground hidden drought arises in areas, such as eastern and southern Asia, where aquifers are already overexploited and may exploited more with the potential of renewable energies.
In a village in Nepal, Netra Chhetri, a researcher of the American University of Arizona Netra Chhetri saw the first panels five years ago, a technological phenomenon that has quickly changed people and policies. The inhabitants of the area have used solar energy to diversify their crops and no longer cultivate only harvest rice, but also corn and vegetables, increasing production by 60%.
In the Middle East, the expert of the Organization of the UN for Food and Agriculture (FAO), Ahmed Abdelfatah, predicted a boom in business competition in that sector.
North Africa usually enjoys 330 sunny days a year and losses up to 15% of its energy transporting it to arid areas, so solar panels are an in situ alternative.
The use of surface water from rivers and reservoirs can also reduce the pressure on aquifers.
The expert from the Polytechnic University of Madrid, Rita Almeida, said that, apart from energy sources, we should also think about changing irrigation systems. The project in which she is participating seeks a 100% renewable energy consumption and reducing water consumption by 30%.
Almeida spoke about the construction of tanks in Spain that serve to supply the entire community of irrigators. The tanks are then covered with solar panels, which allow making better use of space and avoid the evaporation of water.