Israel has led the world in stem-cell research papers per capita since 2000. Israeli universities are ranked among the top 50 world universities in computer science (Technion and Tel Aviv University), mathematics (Hebrew University of Jerusalem) and chemistry (Weizmann Institute of Science). In 2012, Israel was ranked ninth in the world by the Futron's Space Competitiveness Index. The Israel Space Agency coordinates all Israeli space research programs with scientific and commercial goals, and have indigenously designed and built at least 13 commercial, research and spy satellites. Some of Israel's satellites are ranked among the world's most advanced space systems. Shavit is a space launch vehicle produced by Israel to launch small satellites into low Earth orbit. It was first launched in 1988, making Israel the eighth nation to have a space launch capability. In 2003, Ilan Ramon became Israel's first astronaut, serving as payload specialist of STS-107, the fatal mission of the Space Shuttle "Columbia". The ongoing shortage of water in the country has spurred innovation in water conservation techniques, and a substantial agricultural modernization, drip irrigation, was invented in Israel. Israel is also at the technological forefront of desalination and water recycling. The Sorek desalination plant is the largest seawater reverse osmosis (SWRO) desalination facility in the world. By 2014, Israel's desalination programs provided roughly 35% of Israel's drinking water and it is expected to supply 40% by 2015 and 70% by 2050. , more than 50 percent of the water for Israeli households, agriculture and industry is artificially produced. The country hosts an annual Water Technology and Environmental Control Exhibition & Conference (WATEC) that attracts thousands of people from across the world. In 2011, Israel's water technology industry was worth around $2 billion a year with annual exports of products and services in the tens of millions of dollars. As a result of innovations in reverse osmosis technology, Israel is set to become a net exporter of water in the coming years. Israel has embraced solar energy; its engineers are on the cutting edge of solar energy technology and its solar companies work on projects around the world. Over 90% of Israeli homes use solar energy for hot water, the highest per capita in the world. According to government figures, the country saves 8% of its electricity consumption per year because of its solar energy use in heating. The high annual incident solar irradiance at its geographic latitude creates ideal conditions for what is an internationally renowned solar research and development industry in the Negev Desert.