For 4.4 billion people, the only water available is unsafe to drink. In the early 1990s, I was working as a physicist at Lawrence Berkeley National Laboratory (Berkeley Lab") when I heard about a devastating cholera outbreak in my home country. I started to study waterborne pathogens with the aim to develop a new way to make water drinkable that would be affordable and effective in rural areas of low income countries. In a short few years, and later on with funding support from the Energy Department and the U.S. Agency for International Development, I came up with an invention " the UV Waterworks " that met all my goals. It was inexpensive, efficient, portable and effective. Roughly the size of a microwave, the device sanitizes water using UV light to kill harmful bacteria, viruses and molds. It can purify approximately four gallons of water per minute and provide a year's worth of potable drinking water for just seven cents per person. The University of California, which runs the lab, filed the initial patent. I helped found WaterHealth International, which exclusively licensed the UV Waterworks technology from the university in 1996. In the time since, the invention has benefited tens of million people across India and Africa. Roughly 80% of our customers live below the poverty line in their home countries.