Watering the world
Many farms in drought-prone regions of the U.S. rely on drip irrigation as a water-saving method to grow crops. These systems pump water through long thin tubes that stretch across farm fields. Hundreds of dime-sized drippers along the length of each tube trickle water directly onto a plant’s base. A farmer can control the timing and amount of watering, delivering only as much water as a crop requires. Drip irrigation can reduce a farm’s water consumption by as much as 60 percent and increase crop yield by 90 percent, compared with conventional irrigation methods. But these systems are expensive, particularly in off-grid environments where they cost farmers more than $3,000 per acre to install. Now engineers at MIT have found a way to cut the cost of solar-powered drip systems by half, by optimizing the drippers. Furthermore, these new drippers can halve the pumping power required to irrigate, lowering energy bills for...