Worldwide, 100 million ha (harvested) irrigated rice fields annually provide 500 million t (rough) rice, the staple food of 3 billion people. These fields receive 35-40% of all irrigation water, making it the single biggest beneficiary of developed freshwater resources. Possibly more than half of this water is pumped, requiring large amounts of energy. Because of its flooded nature, rice fields emit 5-10% of the world’s methane, a powerful greenhouse gas. Irrigation technologies that reduce water needs in rice fields are needed to help farmers cope with water scarcity while safeguarding food security. At the same time, such technologies can reduce (pumping) energy use and emission of methane.