Zero Mass Water makes solar panel arrays that pull clean drinking water from the air.The $4,500 arrays just launched in the United States.Zero Mass arrays could come in handy in areas where water sources are far away or scarce. Some homeowners have purchased arrays as an alternative to plastic water bottles.Around the world, approximately 2.1 billion people do not have immediate access to clean drinking water. A sustainable water startup called Zero Mass aims to make clean water easily accessible to more people around the world. In 2015, it launched its first product, Source — a solar panel array that harvests and filters water from vapor in the air — in eight countries, including Chile, Jordan, and Peru.Source is now available in the United States, CEO Cody Friesen, a material scientist and MIT alum, told Business Insider.Each panel costs $2,000 (plus a $500 installation fee) and generates an average of two to five liters of water daily, depending on humidity and sunlight. Source can work anywhere, and many arrays are deployed in deserts where water is scarce, Friesen said.Comprised of proprietary materials, the panels use sunlight to produce heat, which allows them to collect water vapor from the air. Friesen wouldn’t disclose what the materials are, but said they have an ideal binding energy for humidity.