A California company is using robots to grow plants in greenhouses that it says use 90 percent less water than traditional farms.The company, Iron Ox, operates several greenhouses and has plans to expand.It recently announced a new $50 million investment.The financing was led by Breakthrough Energy Ventures, a company established by Microsoft founder Bill Gates.At a 930-square meter center in Gilroy, California, Iron Ox uses a self-driving robot named Grover to transport containers of plants.The large greenhouse uses hydroponics, a system designed to grow plants in materials other than soil, such as water.The company says each container, known as a module, carries 30 liters of water and about 70 seedlings as it moves.
